cancer Cancer Signs Cancer Symptoms * Signs or symptoms of Cancer * Seven signs or Symptoms of Cancer Cancer often presents with non-specific features that may also be explained by benign, more common causes. This makes a high index of suspicion necessary in order to investigate and diagnose it correctly. Signs and symptoms of Cancer Signs and symptoms will depend on the size of the cancer, where the cancer is, and how much it affects the surrounding organs or structures. The common mechanisms that cause symptoms are compression, occlusion, erosion and invasion of organs and structures, such as nerves, joints and vessels. If a cancer metastasises, then symptoms may appear in different parts of the body. For example, in certain parts of the brain, even the smallest tumour may produce symptoms. In contrast, pancreatic cancers may not cause symptoms until the disease is advanced. In some cancers, the metastases may produce symptoms before the primary tumour. In prostate cancer, it is not uncommon for bone/joint pain to precede any urinary symptoms. Some general signs and symptoms of cancer include: * Weight loss: unexplained (unintentional) weight loss may be the first sign of cancer, particularly cancers of the pancreas, stomach, oesophagus, or lung. * Fatigue: may be an early or late symptom. * Fever or night sweats: more often seen in advanced disease. * Pain: often a symptom of advanced disease. * Skin changes: certain cancers can produce visible skin signs such as hyperpigmentation, jaundice, erythema, itching, or excessive hair growth. More specific signs and symptoms include: * Change in bowel habit/bladder function: chronic constipation or diarrhoea may be a sign of colon cancer. * Unusual bleeding or discharge: blood in sputum, faeces or urine; abnormal breast or vaginal discharge. * Difficulty swallowing (dysphagia): may indicate cancer of the oesophagus, stomach, or pharynx. * Hoarseness/cough: A persistent cough may be a sign of lung cancer. Hoarseness may indicate cancer of the larynx. * Non-healing sores: A persistent sore in the mouth could be an oral cancer and should be dealt with promptly, especially in patients who smoke, chew tobacco, or frequently drink alcohol. The Seven Signs and Symptoms of Cancer Many people refer to the "Seven Signs and Symptoms of Cancer": * Change in bowel or bladder habits. * A sore on the skin or in the mouth that does not heal. * Unusual bleeding or discharge from the rectum, bladder or vagina. * A new lump in the breast or testes. * Indigestion or trouble swallowing. * Obvious changes to moles or warts. * Nagging cough or hoarseness that persists for four to six weeks.

Cancer is the uncontrolled growth of abnormal cells in the body

Cancer is the uncontrolled growth of abnormal cells in the body

Cancerous cells are also called malignant cells.

Recent findings and perspectives on medical research.

Six Killers | Cancer

Cancer Patients, Lost in a Maze of Uneven Care

By DENISE GRADY

Treating cancer can be very complicated, and it is difficult for even the most educated patients to be sure they have the best care.

Alternative Names

Carcinoma; Malignant tumor.

Causes

Cells are the building blocks of living things. Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells “forget” how to die.
There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.
There are many causes of cancers, including:

• Benzene and other chemicals
• Certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
• Certain viruses
• Radiation
• Sunlight
• Tobacco

However, the cause of many cancers remains unknown.
The most common cause of cancer-related death is lung cancer.
The three most common cancers in men in the United States are:

• Prostate cancer
• Lung cancer
• Colon cancer

In women in the U.S., the three most common cancers are:

• Breast cancer
• Colon cancer
• Lung cancer

Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of gastric cancer, but in the U.S. this type of cancer is pretty rare. Differences in diet may play a role.
Some other types of cancers include:

• Brain cancer
• Cervical cancer
• Hodgkin's lymphoma
• Kidney cancer
• Leukemia
• Liver cancer
• Non-Hodgkin's lymphoma
• Ovarian cancer
• Skin cancer
• Testicular cancer
• Thyroid cancer
• Uterine cancer

Skin Cancer

Skin Cancer

What Is Skin Cancer?

Skin cancer is a malignant growth on the skin which can have many causes. The most common skin cancers are basal cell cancer, squamous cell cancer, and melanoma which all trace back to the mutation of melanin cells. Skin cancer generally develops in the epidermis (the outermost layer of skin), so a tumor is usually clearly visible. This makes most skin cancers detectable in the early stages. There are three common and likely types of skin cancer, each of which is named after the type of skin cell from which it arises. Unlike many other cancers, including those originating in the lung, pancreas, and stomach, only a small minority of those afflicted will actually die of the disease.Skin cancer represents the most commonly diagnosed cancer, surpassing lung, breast, colorectal and prostate cancer.Melanoma is less common than basal cell carcinoma and squamous cell carcinoma, but it is the most serious—for example, in the UK there are 9,500 new cases of melanoma each year, and 2,300 deaths.More people now die of melanoma in the UK than in Australia. It is the most common cancer in the young population (20 – 39 age group).It is estimated that approximately 85% of cases are caused by too much sun.^{[citation needed]} Non-melanoma skin cancers are the most common skin cancers. The majority of these are called basal cell carcinomas. These are usually localised growths caused by excessive cumulative exposure to the sun and do not tend to spread.

Risk factors

Skin cancer has many potential causes, these include:

1. Studies have show that smoking tobacco and related products can double the risk of skin cancer.
2. Overexposure to UV-radiation may cause skin cancer either via the direct DNA damage or via the indirect DNA damage mechanism. Overexposure (burning) UVA & UVB have both been implicated in causing DNA damage resulting in cancer. Sun exposure between 10AM and 4PM is most intense and therefore most harmful. Natural (sun) & artificial UV exposure (tanning salons) are possibly associated with skin cancer.
   1. UVB rays primarily affect the epidermis causing sunburns, redness, and blistering of the skin when overexposed. The melanin of the epidermis is activated with UVB just as with UVA; however, the effects are longer lasting with pigmentation continuing over 24 hours.
3. Chronic non-healing wounds, especially burns. These are called Marjolin's ulcers based on their appearance, and can develop into squamous cell carcinoma.
4. Genetic predisposition, including "Congenital Melanocytic Nevi Syndrome". CMNS is characterized by the presence of "nevi" or moles of varying size that either appear at or within 6 months of birth. Nevi larger than 20 mm (3/4") in size are at higher risk for becoming cancerous.
5. Human papilloma virus (HPV) is often associated with squamous cell carcinoma of the genital, anal, oral, pharynx, and fingers. It is believed that the HPV vaccine might help to prevent these cancers as well as cervical cancers.
6. Skin cancer is one of the potential dangers of ultraviolet germicidal irradiation.

Complied From Wkikpedia.com

Oral Cancer

Oral Cancer

What is oral Cancer?

Oral cancer is any cancerous tissue growth located in the mouth. It may arise as a primary lesion originating in any of the oral tissues, by metastasis from a distant site of origin, or by extension from a neighboring anatomic structure, such as the nasal cavity or the maxillary sinus. Oral cancers may originate in any of the tissues of the mouth, and may be of varied histologic types: teratoma, adenocarcinoma derived from a major or minor salivary gland, lymphoma from tonsillar or other lymphoid tissue, or melanoma from the pigment producing cells of the oral mucosa. Far and away the most common oral cancer is squamous cell carcinoma, originating in the tissues that line the mouth and lips. Oral or mouth cancer most commonly involves the tissue of the lips or the tongue. It may also occur on the floor of the mouth, cheek lining, gingiva (gums), or palate (roof of the mouth). Most oral cancers look very similar under the microscope and are called squamous cell carcinoma. These are malignant and tend to spread rapidly.

Symptoms

Skin lesion, lump, or ulcer:

• On the tongue, lip, or other mouth area
• Usually small
• Most often pale colored, may be dark or discolored
• Early sign may be a white patch (leukoplakia) or a red patch (erythroplakia) on the soft tissues of the mouth
• Usually painless initially
• May develop a burning sensation or pain when the tumor is advanced

Additional symptoms that may be associated with this disease:

• Tongue problems
• Swallowing difficulty
• Mouth sores that do not resolve in 14 days
• Pain and paraesthesia are late symptoms.

Signs and tests

An examination of the mouth by the health care provider or dentist shows a visible and/or palpable (can be felt) lesion of the lip, tongue, or other mouth area. As the tumor enlarges, it may become an ulcer and bleed. Speech/talking difficulties, chewing problems, or swallowing difficulties may develop, particularly if the cancer is on the tongue.
There are a variety of screening devices that assist doctors in detecting oral cancer, including the Velscope, Vizilite Plus and the identafi 3000. While a dentist, physician or other medical professional may suspect a particular lesion is malignant, the only definitive method for determining this is through biopsy and microscopic evaluation of the cells in the removed sample. A tissue biopsy, whether of the tongue or other oral tissues, and microscopic examination of the lesion confirm the diagnosis of oral cancer.

Treatment

Surgical excision (removal) of the tumor is usually recommended if the tumor is small enough, and if surgery is likely to result in a functionally satisfactory result. Radiation therapy is often used in conjunction with surgery, or as the definitive radical treatment, especially if the tumour is inoperable. Surgeries for oral cancers include

• Maxillectomy (can be done with or without Orbital exenteration)
• Mandibulectomy (removal of the mandible or lower jaw or part of it)
• Glossectomy (tongue removal, can be total, hemi or partial)
• Radical neck dissection
• Moh's procedure
• Combinational e.g. glossectomy and laryngectomy done together.

Lung Cancer

Lung Cancer

What is Lung Cancer
Lung cancer is a disease of uncontrolled cell growth in tissues of the lung. This growth may lead to metastasis, which is the invasion of adjacent tissue and infiltration beyond the lungs. The vast majority of primary lung cancers are carcinomas of the lung, derived from epithelial cells. Lung cancer, the most common cause of cancer-related death in men and also the most common in women, is responsible for 1.3 million deaths worldwide annually.^[1] The most common symptoms are shortness of breath, coughing (including coughing up blood), and weight loss.
The main types of lung cancer are small cell lung carcinoma and non-small cell lung carcinoma. This distinction is important, because the treatment varies; non-small cell lung carcinoma (NSCLC) is sometimes treated with surgery, while small cell lung carcinoma (SCLC) usually responds better to chemotherapy and radiation.The most common cause of lung cancer is long-term exposure to tobacco smoke.The occurrence of lung cancer in nonsmokers, who account for as many as 15% of cases, is often attributed to a combination of genetic factors,^[6][7] radon gas,asbestos,and air pollution, including secondhand smoke.
Lung cancer may be seen on chest radiograph and computed tomography (CT scan). The diagnosis is confirmed with a biopsy. This is usually performed via bronchoscopy or CT-guided biopsy. Treatment and prognosis depend upon the histological type of cancer, the stage (degree of spread), and the patient's performance status. Possible treatments include surgery, chemotherapy, and radiotherapy. With treatment, the five-year survival rate is 14%

Signs and symptoms

Symptoms that suggest lung cancer include:

• dyspnea (shortness of breath)
• hemoptysis (coughing up blood)
• chronic coughing or change in regular coughing pattern
• wheezing
• chest pain or pain in the abdomen
• cachexia (weight loss), fatigue, and loss of appetite
• dysphonia (hoarse voice
• clubbing of the fingernails (uncommon)
• dysphagia (difficulty swallowing).

Causes

The main causes of lung cancer (and cancer in general) include carcinogens (such as those in tobacco smoke), ionizing radiation, and viral infection. This exposure causes cumulative changes to the DNA in the tissue lining the bronchi of the lungs (the bronchial epithelium). As more tissue becomes damaged, eventually a cancer develops.^[3]

Breast Cancer

Breast Cancer

Waht is Breast Cancer?
Breast cancer is a cancer that starts in the breast, usually in the inner lining of the milk ducts or lobules. There are different types of breast cancer, with different stages (spread), aggressiveness, and genetic makeup. With best treatment, 10-year disease-free survival varies from 98% to 10%. Treatment includes surgery, drugs (hormone therapy and chemotherapy), and radiation.
In the United States, there were 216,000 cases of invasive breast cancer and 40,000 deaths in 2004. Worldwide, breast cancer is the second most common type of cancer after lung cancer (10.4% of all cancer incidence, both sexes counted) and the fifth most common cause of cancer death.In 2004, breast cancer caused 519,000 deaths worldwide (7% of cancer deaths; almost 1% of all deaths).
Breast cancer is about 100 times as frequent among women as among men, but survival rates are equal in both sexes
Some breast cancers require the hormones estrogen and progesterone to grow, and have receptors for those hormones. Those cancers are treated with drugs that interfere with those hormones, usually tamoxifen, and with drugs that shut off the production of estrogen in the ovaries or elsewhere; this may damage the ovaries and end fertility. Low-risk, hormone-sensitive breast cancers may be treated with hormone therapy and radiation alone. Breast cancers without hormone receptors, or which have spread to the lymph nodes in the armpits, or which express certain genetic characeristics, are higher-risk, and are treated more aggressively. One standard regimen, popular in the U.S., is cycophosphamide plus doxorubicin (Adriomycin), known as CA; these drugs damage DNA in the cancer, but also in fast-growing normal cells where they cause serious side effects. Sometimes a taxane drug, such as docetaxel, is added, and the regime is then known as CAT; taxane attacks the microtubules in cancer cells. An equivalent treatment, popular in Europe, is cyclophosphamide, methotrexate, and fluorouracil (CMF).Monoclonal antibodies, such as trastuzumab, are used for cancer cells that have the HER2 mutation. Radiation is usually added to the surgical bed to control cancer cells that were missed by the surgery, which usually extends survival, although radiation exposure to the heart may cause damage and heart failure in the following years.

Causes

The primary risk factors that have been identified are sex,age, childbearing, hormones, a high-fat diet,alcohol intake, obesity, and environmental factors such as tobacco use, radiation^[26] and shiftwork.However, studies of environmental and lifestyle factors only attribute a small increase in breast cancer to each factor. Furthermore, these studies are not randomized, controlled trials, and so they may associate breast cancer with factors that don't actually cause breast cancer
No cause is known for 95% of breast cancer cases, while approximately 5% of new breast cancers are attributable to hereditary syndromes. In particular, carriers of the breast cancer susceptibility genes, BRCA1 and BRCA2, are at a 30-40% increased risk for breast and ovarian cancer, depending on in which portion of the protein the mutation occurs.

• Personal history of breast cancer: A woman who had breast cancer in one breast has an increased risk of getting cancer in her other breast.
• Family history: A woman's risk of breast cancer is higher if her mother, sister, or daughter had breast cancer. The risk is higher if her family member got breast cancer before age 40. Having other relatives with breast cancer (in either her mother's or father's family) may also increase a woman's risk.
• Certain breast changes: Some women have cells in the breast that look abnormal under a microscope. Having certain types of abnormal cells (atypical hyperplasia and lobular carcinoma in situ [LCIS]) increases the risk of breast cancer.
• Race: Breast cancer is diagnosed more often in Caucasian women than Latina, Asian, or African American women.
• No physical activity: Women who are physically inactive throughout life may have an increased risk of breast cancer. Being active may help decrease risk.
• Tamoxifen may interact unfavorably with certain antidepressants when used for prevention of breast cancer recurrence.
• Abortion-breast cancer hypothesis: Mainstream organizations such as the American Cancer Society and National Cancer Institute have concluded there is no link between induced abortion and breast cancer, although a minority of doctors continue to disagree.

Pancreatic cancer

Pancreatic cancer

Pancreatic cancer is a malignant neoplasm of the pancreas. Each year in the United States, about 42,470 individuals are diagnosed with this condition and 35,240 die from the disease. The prognosis is generally poor; less than 5 percent of those diagnosed are still alive five years after diagnosis. Complete remission is still extremely rare.
About 95% of exocrine pancreatic cancers are adenocarcinomas (M8140/3). The remaining 5% include adenosquamous carcinomas, signet ring cell carcinomas, hepatoid carcinomas, colloid carcinomas, undifferentiated carcinomas, and undifferentiated carcinomas with osteoclast-like giant cells.^[3] Exocrine pancreatic cancers are far more common than endocrine pancreatic cancers (also known as islet cell carcinomas), which make up about 1% of total cases.

Signs and symptoms

Pancreatic cancer is sometimes called a "silent killer" because early pancreatic cancer often does not cause symptoms,^[5] and the later symptoms are usually non-specific and varied.^[5] Therefore, pancreatic cancer is often not diagnosed until it is advanced.^[5] Common symptoms include:

• Pain in the upper abdomen that typically radiates to the back^[5] (seen in carcinoma of the body or tail of the pancreas)
• Loss of appetite and/or nausea and vomiting^[5]
• Significant weight loss
• Painless jaundice (yellow skin/eyes, dark urine)^[5] when a cancer of the head of the pancreas (about 60% of cases) obstructs the common bile duct as it runs through the pancreas. This may also cause pale-colored stool and steatorrhea.
• Trousseau sign, in which blood clots form spontaneously in the portal blood vessels, the deep veins of the extremities, or the superficial veins anywhere on the body, is sometimes associated with pancreatic cancer.
• Diabetes mellitus, or elevated blood sugar levels. Many patients with pancreatic cancer develop diabetes months to even years before they are diagnosed with pancreatic cancer, suggesting that new onset diabetes in an elderly individual may be an early warning sign of pancreatic cancer.^[6]
• Clinical depression has been reported in association with pancreatic cancer, sometimes presenting before the cancer is diagnosed. However, the mechanism for this association is not known.^[7]

Diagnosis

Most patients with pancreatic cancer experience pain, weight loss, or jaundice.^[32]
Pain is present in 80 to 85 percent of patients with locally advanced or advanced metastic disease. The pain is usually felt in the upper abdomen as a dull ache that radiates straight through to the back. It may be intermittent and made worse by eating. Weight loss can be profound; it can be associated with anorexia, early satiety, diarrhea, or steatorrhea. Jaundice is often accompanied by pruritus and dark urine. Painful jaundice is present in approximately one-half of patients with locally unresectable disease, while painless jaundice is present in approximately one-half of patients with a potentially resectable and curable lesion.
The initial presentation varies according to location of the cancer. Malignancies in the pancreatic body or tail usually present with pain and weight loss, while those in the head of the gland typically present with steatorrhea, weight loss, and jaundice. The recent onset of atypical diabetes mellitus, a history of recent but unexplained thrombophlebitis (Trousseau sign), or a previous attack of pancreatitis are sometimes noted.
Courvoisier sign defines the presence of jaundice and a painlessly distended gallbladder as strongly indicative of pancreatic cancer, and may be used to distinguish pancreatic cancer from gallstones.
Tiredness, irritability and difficulty eating due to pain also exist. Pancreatic cancer is usually discovered during the course of the evaluation of aforementioned symptoms.
Liver function tests can show a combination of results indicative of bile duct obstruction (raised conjugated bilirubin, γ-glutamyl transpeptidase and alkaline phosphatase levels). CA19-9 (carbohydrate antigen 19.9) is a tumor marker that is frequently elevated in pancreatic cancer. However, it lacks sensitivity and specificity. When a cutoff above 37 U/mL is used, this marker has a sensitivity of 77% and specificity of 87% in discerning benign from malignant disease. CA 19-9 might be normal early in the course, and could be elevated due to benign causes of biliary obstruction.^[33]
Imaging studies, such as computed tomography (CT scan) can be used to identify the location of the cancer. Endoscopic ultrasound (EUS) is another procedure that can help visualize the location and can serve to guide a percutaneous needle biopsy, which is necessary to establish a definitive diagnosis.

Bladder cancer

Bladder cancer

Bladder cancer refers to any of several types of malignant growths of the urinary bladder. It is a disease in which abnormal cells multiply without control in the bladder.The bladder is a hollow, muscular organ that stores urine; it is located in the pelvis. The most common type of bladder cancer begins in cells lining the inside of the bladder and is called transitional cell carcinoma (sometimes urothelial cell carcinoma).

Signs and symptoms

Bladder cancer characteristically causes blood in the urine; this may be visible to the naked eye (frank hematuria) or detectable only by microscope (microscopic hematuria). Other possible symptoms include pain during urination, frequent urination (Polyuria) or feeling the need to urinate without results. These signs and symptoms are not specific to bladder cancer, and are also caused by non-cancerous conditions, including prostate infections and cystitis. Kidney cancer also can cause hematuria.

Causes

Tobacco smoking is the main known cause of urinary bladder cancer: in most populations, smoking causes over half of bladder cancer cases in men and a sizeable proportion in women. There is a linear relationship between smoking and risk, and quitting smoking reduces the risk.^[2] In a 10-year study involving almost 48,000 men, researchers found that men who drank 1.5L of water a day had a significantly reduced incidence of bladder cancer when compared with men who drank less than 240mL (around 1 cup) per day. The authors proposed that bladder cancer might partly be caused by the bladder directly contacting carcinogens that are excreted in urine. It is postulated, therefore, that by drinking higher quantities of water, urine is more dilute, thereby reducing the chance of disease.^{[citation needed]} Thirty percent of bladder tumors probably result from occupational exposure in the workplace to carcinogens such as benzidine. 2-Naphthylamine, which is found in cigarette smoke, has also been shown to increase bladder cancer risk. Occupations at risk are metal industry workers, rubber industry workers, workers in the textile industry, and people who work in printing. Some studies also suggest that auto mechanics have an elevated risk of bladder cancer due to their frequent exposure to hydrocarbons and petroleum-based chemicals.^[3] Hairdressers are thought to be at risk as well because of their frequent exposure to permanent hair dyes. It has been proposed that hair dyes are a risk factor, and some have shown an odds ratio of 2.1 to 3.3 for risk of developing bladder cancer among women who use permanent hair dyes, while others have shown no correlation between the use of hair dyes and bladder cancer.^{[citation needed]} Certain drugs such as cyclophosphamide and phenacetin are known to predispose to bladder TCC.^{[citation needed]} Chronic bladder irritation (infection, bladder stones, catheters, bilharzia) predisposes to squamous cell carcinoma of the bladder.^{[citation needed]} Approximately 20% of bladder cancers occur in patients without predisposing risk factors.^{[citation needed]}

Diagnosis

The gold standard for diagnosing bladder cancer is biopsy obtained during cystoscopy. Sometimes it is an incidental finding during cystoscopy.^[4] Urine cytology can be obtained in voided urine or at the time of the cystoscopy ("bladder washing"). Cytology is very specific (a positive result is highly indicative of bladder cancer) but suffers from low sensitivity (a negative result does not exclude the diagnosis of cancer). There are newer urine bound markers for the diagnosis of bladder cancer. These markers are more sensitive but not as specific as urine cytology. They are much more expensive as well. Many patients with a history, signs, and symptoms suspicious for bladder cancer are referred to a urologist or other physician trained in cystoscopy, a procedure in which a flexible tube bearing a camera and various instruments is introduced into the bladder through the urethra. Suspicious lesions may be biopsied and sent for pathologic analysis

Colorectal cancer

Colorectal cancer

Colorectal cancer, also called colon cancer or large bowel cancer, includes cancerous growths in the colon, rectum and appendix. With 655,000 deaths worldwide per year, it is the third most common form of cancer and the third leading cause of cancer-related death in the Western world.^[1] Many colorectal cancers are thought to arise from adenomatous polyps in the colon. These mushroom-shaped growths are usually benign, but some may develop into cancer over time. The majority of the time, the diagnosis of localized colon cancer is through colonoscopy. Therapy is usually through surgery, which in many cases is followed by chemotherapy.

Symptoms

The symptoms of colorectal cancer depend on the location of tumor in bowel and whether it has spread to elsewhere in the body (metastasis). Most of the symptoms may occur in other diseases as well, and hence none of the symptoms mentioned here is diagnostic of colorectal cancer. Symptoms and signs are divided into local, constitutional (affecting the whole body) and metastatic (caused by spread to other organs).

Local symptoms

Local symptoms are more likely if the tumor is located closer to the anus. There may be a change in bowel habit (new-onset constipation or diarrhea in the absence of another cause), and a feeling of incomplete defecation (tenesmus) and reduction in diameter of stool; tenesmus and change in stool shape are both characteristic of rectal cancer. Lower gastrointestinal bleeding, including the passage of bright red blood in the stool, may indicate colorectal cancer, as may the increased presence of mucus. Melena, black stool with a tarry appearance, normally occurs in upper gastrointestinal bleeding (such as from a duodenal ulcer) but is sometimes encountered in colorectal cancer when the disease is located in the beginning of the large bowel.
A tumor that is large enough to fill the entire lumen of the bowel may cause bowel obstruction. This situation is characterized by constipation, abdominal pain, abdominal distension and vomiting. This occasionally leads to the obstructed and distended bowel perforating and causing peritonitis.
Certain local effects of colorectal cancer occur when the disease has become more advanced. A large tumor is more likely to be noticed on feeling the abdomen, and it may be noticed by a doctor on physical examination. The disease may invade other organs, and may cause blood or air in the urine (invasion of the bladder) or vaginal discharge (invasion of the female reproductive tract).

Constitutional symptoms

If a tumor has caused chronic occult bleeding, iron deficiency anemia may occur; this may be experienced as fatigue, palpitations and noticed as pallor (pale appearance of the skin). Colorectal cancer may also lead to weight loss, generally due to a decreased appetite.
More unusual constitutational symptoms are an unexplained fever and one of several paraneoplastic syndrome. The most common paraneoplastic syndrome is thrombosis, usually deep vein thrombosis.

Metastatic symptoms

Colorectal cancer most commonly spreads to the liver. This may go unnoticed, but large deposits in the liver may cause jaundice and abdominal pain (due to stretching of the capsule). If the tumor deposit obstructs the bile duct, the jaundice may be accompanied by other features of biliary obstruction, such as pale stools.

Endometrial cancer

Endometrial cancer

Endometrial cancer refers to several types of malignancy which arise from the endometrium, or lining of the uterus. Endometrial cancers are the most common gynecologic cancers in the United States, with over 35,000 women diagnosed each year in the U.S. The most common subtype, endometrioid adenocarcinoma, typically occurs within a few decades of menopause, is associated with excessive estrogen exposure, often develops in the setting of endometrial hyperplasia, and presents most often with vaginal bleeding. Endometrial carcinoma is the third most common cause of gynecologic cancer death (behind ovarian and cervical cancer). A total abdominal hysterectomy (surgical removal of the uterus) with bilateral salpingo-oophorectomy is the most common therapeutic approach.
Endometrial cancer may sometimes be referred to as uterine cancer. However, different cancers may develop not only from the endometrium itself but also from other tissues of the uterus, including cervical cancer, sarcoma of the myometrium, and trophoblastic disease.

Classification

Most endometrial cancers are carcinomas (usually adenocarcinomas), meaning that they originate from the single layer of epithelial cells which line the endometrium and form the endometrial glands. There are many microscopic subtypes of endometrial carcinoma, including the common endometrioid type, in which the cancer cells grow in patterns reminiscent of normal endometrium, and the far more aggressive uterine papillary serous carcinoma|papillary serous carcinoma and clear cell endometrial carcinomas. Some authorities have proposed that endometrial carcinomas be classified into two pathogenetic groups:^[1]

• Type I: These cancers occur most commonly in pre- and peri-menopausal women, often with a history of unopposed estrogen exposure and/or endometrial hyperplasia. They are often minimally invasive into the underlying uterine wall, are of the low-grade endometrioid type, and carry a good prognosis.

• Type II: These cancers occur in older, post-menopausal women, are more common in African-Americans, are not associated with increased exposure to estrogen, and carry a poorer prognosis. They include:

• the high-grade endometrioid cancer,
• the uterine papillary serous carcinoma,
• the uterine clear cell carcinoma.

In contrast to endometrial carcinomas, the uncommon endometrial stromal sarcomas are cancers which originate in the non-glandular connective tissue of the endometrium. Uterine carcinosarcoma, formerly called Malignant mixed müllerian tumor, is a rare uterine cancer which contains cancerous cells of both glandular and sarcomatous appearance - in this case, the cell of origin is unknown.^[2]

Signs and symptoms

• Vaginal bleeding and/or spotting in postmenopausal women
• Abnormal uterine bleeding, abnormal menstrual periods
• Bleeding between normal periods in premenopausal women in women older than 40: extremely long, heavy, or frequent episodes of bleeding (may indicate premalignant changes)
• Anemia, caused by chronic loss of blood. (This may occur if the woman has ignored symptoms of prolonged or frequent abnormal menstrual bleeding.)
• Lower abdominal pain or pelvic cramping
• Thin white or clear vaginal discharge in postmenopausal women.

Risk factors

• high levels of estrogen
• endometrial hyperplasia
• obesity
• hypertension
• polycystic ovary syndrome^{[citation needed]}
• nulliparity (never having carried a pregnancy)
• infertility (inability to become pregnant)
• early menarche (onset of menstruation)
• late menopause (cessation of menstruation)
• endometrial polyps or other benign growths of the uterine lining
• diabetes
• Tamoxifen
• high intake of animal fat^{[citation needed]}
• pelvic radiation therapy
• breast cancer
• ovarian cancer
• heavy daily alcohol consumption (possibly a risk factor)[3] ^[3]

Prostate cancer

Prostate cancer

Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. The cancer cells may metastasize (spread) from the prostate to other parts of the body, particularly the bones and lymph nodes. Prostate cancer may cause pain, difficulty in urinating, problems during sexual intercourse, or erectile dysfunction. Other symptoms can potentially develop during later stages of the disease.

Symptoms

Early prostate cancer usually causes no symptoms. Often it is diagnosed during the workup for an elevated PSA noticed during a routine checkup. Sometimes, however, prostate cancer does cause symptoms, often similar to those of diseases such as benign prostatic hypertrophy. These include frequent urination, increased urination at night, difficulty starting and maintaining a steady stream of urine, blood in the urine, and painful urination. Prostate cancer is associated with urinary dysfunction as the prostate gland surrounds the prostatic urethra. Changes within the gland, therefore, directly affect urinary function. Because the vas deferens deposits seminal fluid into the prostatic urethra, and secretions from the prostate gland itself are included in semen content, prostate cancer may also cause problems with sexual function and performance, such as difficulty achieving erection or painful ejaculation.^[6]
Advanced prostate cancer can spread to other parts of the body, possibly causing additional symptoms. The most common symptom is bone pain, often in the vertebrae (bones of the spine), pelvis, or ribs. Spread of cancer into other bones such as the femur is usually to the proximal part of the bone. Prostate cancer in the spine can also compress the spinal cord, causing leg weakness and urinary and fecal incontinence.^[7]

Causes

The specific causes of prostate cancer remain unknown.^[8] A man's risk of developing prostate cancer is related to his age, genetics, race, diet, lifestyle, medications, and other factors. The primary risk factor is age. Prostate cancer is uncommon in men younger than 45, but becomes more common with advancing age. The average age at the time of diagnosis is 70.^[9] However, many men never know they have prostate cancer. Autopsy studies of Chinese, German, Israeli, Jamaican, Swedish, and Ugandan men who died of other causes have found prostate cancer in thirty percent of men in their 50s, and in eighty percent of men in their 70s.^[10] In the year 2005 in the United States, there were an estimated 230,000 new cases of prostate cancer and 30,000 deaths due to prostate cancer.^[11]

Thyroid CANCER

Thyroid CANCER

Thyroid neoplasm or thyroid cancer usually refers to any of four kinds of malignant tumors of the thyroid gland: papillary, follicular, medullary or anaplastic.^[1] Most patients are 25 to 65 years of age when first diagnosed; women are more affected than men.^[1] Papillary and follicular tumors are the most common. They grow slowly and may recur, but are generally not fatal in patients under 45 years of age. Medullary tumors have a good prognosis if restricted to the thyroid gland and a poorer prognosis if metastasis occurs. Anaplastic tumors are fast-growing and respond poorly to therapy.
Thyroid nodules are diagnosed by ultrasound guided fine needle aspiration (USG/FNA) or frequently by thyroidectomy (surgical removal and subsequent histological examination). As thyroid cancer can take up iodine, radioactive iodine is commonly used to treat thyroid carcinomas, followed by TSH suppression by high-dose thyroxine therapy.

Symptoms

Most often the first symptom of thyroid cancer is a nodule in the thyroid region of the neck.^[1] However, many adults have small nodules in their thyroids. But typically under 5% of these nodules are found to be malignant. Sometimes the first sign is an enlarged lymph node. Later symptoms that can be present are pain in the anterior region of the neck and changes in voice.
Thyroid cancer is usually found in a euthyroid patient, but symptoms of hyperthyroidism or hypothyroidism may be associated with a large or metastatic well-differentiated tumor.
Nodules are of particular concern when they are found in those under the age of 20. The presentation of benign nodules at this age is less likely, and thus the potential for malignancy is far greater.

Diagnosis

After a nodule is found during a physical examination, a referral to an endocrinologist, a thyroidologist or otolaryngologist may occur. Most commonly an ultrasound is performed to confirm the presence of a nodule, and assess the status of the whole gland. Measurement of thyroid stimulating hormone and anti-thyroid antibodies will help decide if there is a functional thyroid disease such as Hashimoto's thyroiditis present, a known cause of a benign nodular goiter.

Treatment

If the nodule is benign, patients may receive thyroxine therapy to supress thyroid-stimulating hormone and should be reevaluated in 6 months.^[1]
If the nodule is malignant or has indeterminate cytologic features, it may require surgery. Common surgeries include thyroidectomy, lobectomy, and tracheostomy.^[1]
Radioactive Iodine-131 is used in patients with papillary or follicular thyroid cancer for ablation of residual thyroid tissue after surgery and for the treatment of thyroid cancer. Patients with medullary, anaplastic, and most Hurthle cell cancers do not benefit from this therapy.^[1]
External irradiation may be used when the cancer is unresectable, when it recurs after resection, or to relieve pain from bone metastasis.^[1]

Picornavirus

A Picornavirus is a virus belonging to the family Picornaviridae. Picornaviruses are non-enveloped, positive-stranded RNA viruses with an icosahedral capsid. The genome RNA is unusual because it has a protein on the 5' end that is used as a primer for transcription by RNA polymerase. The name is derived from pico meaning small, and RNA referring to the ribonucleic acid genome, so "picornavirus" literally means small RNA virus.

Picornaviruses are separated into nine distinct genera and include many important pathogens of humans and animals.^[1] The diseases they cause are varied, ranging from acute "common-cold"-like illnesses, to poliomyelitis, to chronic infections in livestock. Two main categories are enteroviruses and rhinoviruses.

Classification

Picornaviruses are classed under Baltimore's viral classification system as group IV viruses as they contain a single stranded, positive sense RNA genome of between 7.2 and 9.0 kb in length. Like most positive sense RNA genomes, the genetic material alone is infectious; although substantially less virulent than if contained within the viral particle, the RNA can have increased infectivity when transfected into cells. The genome itself is the same sense as mammalian mRNA, being read 5’ to 3’. Unlike mammalian mRNA Picornaviruses do not have a 5’ CAP but a virally encoded protein known as VPg, however like mammalian mRNA the genome does have a poly A tail at the 3’ end. There is an un-translated region (UTR) at both ends of the Picornavirus genome. The 5’ UTR is longer, being around 600-1200 BP in length, compared to that of the 3’ UTR, which is around 50-100bp. It is thought that the 5’ UTR is important in translation and the 3’ in negative strand synthesis; however the 5’ end may also have a role to play in virulence of the virus. The rest of the genome encodes structural proteins at the 5’ end and non-structural proteins at the 3’ end in a single polyprotein. Experimental data from single step growth-curve-like experiments have allowed scientists to look at the replication of the picornaviruses in great detail. The whole of replication occurs within the host cell cytoplasm and infection can even happen in cells that do not contain a nucleus (known as enucleated cells) and those treated with actinomycin D (this antibiotic would inhibit viral replication if this occurred in the nucleus.)

Picornaviruses are separated into nine distinct genera. Contained within the picornavirus family are many organisms of importance as vertebrate and human pathogens, shown in the table below.

Picornavirus Genera, Species and Serotypes
Genus	Species (* signifies type species)	Serotypes
Enterovirus	Bovine enterovirus	two types: bovine enterovirus (BEV) 1 and BEV-2
	Human enterovirus A	21 types including some coxsackie A viruses and enteroviruses
	Human enterovirus B	57 types including enteroviruses, coxsackie B viruses, echoviruses, and swine vesicular disease virus
	Human enterovirus C	14 types including some coxsackie A viruses and enteroviruses
	Human enterovirus D	three types: EV-68, EV-70, EV-94
	Poliovirus *	three types: poliovirus (PV) 1, PV-2 and PV-3
	Porcine enterovirus A	one type: porcine enterovirus (PEV) 8
	Porcine enterovirus B	two types: PEV-9 and PEV-10
	Simian enterovirus A	one type: simian enterovirus (SEV) A1
Rhinovirus	Human rhinovirus A *	74 serotypes
	Human rhinovirus B	25 serotypes
	Human rhinovirus C	7 serotypes
Hepatovirus (also classed as Heparnavirus)	Hepatitis A virus *	one serotype: Hepatitis A virus (HAV)
	Avian encephalomyelitis-like viruses	one type: avian encephalomyelitis virus (AEV)
Cardiovirus	Encephalomyocarditis virus *	one serotype: encephalomyocarditis virus (EMCV). Note: Columbia SK virus, Maus Elberfeld virus and Mengovirus are strains of EMCV.
	Theilovirus	five types: Theiler's murine encephalomyellitis virus (TMEV), Vilyuisk human encephalomyelitis virus (VHEV), Theiler-like virus (TLV) of rats, Saffold virus (SAFV) 1 and SAFV-2
Aphthovirus	Foot-and-mouth disease virus[2] *	seven serotypes: O, A, C, Southern African Territories (SAT) 1, SAT 2, SAT 3 and Asia 1
	Equine rhinitis A virus	single serotype: equine rhinitis A virus (ERAV)
Parechovirus	Human parechovirus *	six types: Human parechovirus (HPeV) 1, HPeV-2, HPeV-3, HPeV-4, HPeV-5, HPeV-6
	Ljungan virus	Possibly three types have been described
Erbovirus	Equine rhinitis B virus *	Three types: equine rhinitis B virus (ERBV) 1, ERBV-2, ERBV-3
Kobuvirus	Aichi virus *	single serotype: Aichi virus (AiV)
	Bovine kobuvirus	Single serotype: bovine kobuvirus (BKV)
Teschovirus	Porcine teschovirus *	11 serotypes: porcine teschovirus (PTV) 1 to PTV-11
Sources "Picornaviridae". Medical Subject Headings (MeSH). National Library of Medicine. http://www.nlm.nih.gov/cgi/mesh/2007/MB_cgi?term=Picornaviridae. Retrieved 2007-09-03.  "Picornavirus". Institute for Animal Health. http://www.picornaviridae.com/. Retrieved 2007-09-03.  Büchen-Osmond, C., ed (2006). "ICTVdB - The Universal Virus Database, version 4". Columbia University, New York, USA. http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/.  Kahn, Cynthia M.; Line, Scott, eds. (2005-02-08), "Porcine Enteroviral Encephalomyelitis", The Merck Veterinary Manual (9th ed.), Merck, ISBN 0911910506

Enteroviruses infect the enteric tract as it is visible from its name. On the other hand, rhinoviruses infect primarily the nose and the throat. Enteroviruses replicate at 37°C, whereas Rhinoviruses grow better at 33°C, as this is the lower temperature of the nose. Enteroviruses are stable under acid conditions and thus they are able to survive exposure to gastric acid. In contrast, Rhinoviruses are acid-labile and that is the reason why Rhinoviruses are restricted to the nose and throat.

Plant picornaviruses

The plant picornaviruses have a number of properties that are distinct from the animal viruses. They have been classified into a superfamily Secoviridae containing the families Comoviridae (genera Comovirus, Fabavirus and Nepovirus), Sequiviridae (genera Sequivirus and Waikavirus) and a number of unassigned genera (Cheravirus, Sadwavirus and Torradovirus (type species Tomato torrado virus)).^[3]

Virology

Structure

The capsid is an arrangement of 60 protomers in a tightly packed Icosahedral structure. Each protometer consists of 4 polypeptides known as VP (viral protein)1, 2, 3 and 4. VP2 and VP4 polypeptides originate from one protomer known as VP0 that is cleaved to give the different capsid components. The Icosahedral is said to have a triangulation number of 3, this means that in the icosahedral structure each of the 60 triangles that make up the capsid are split into 3 little triangles with a subunit on the corner. Depending on the type and degree of dehydration the viral particle is around 27-30 nm in diameter. The viral genome is around 2500 nm in length so we can therefore conclude that it must be tightly packaged within the capsid along with substances such as sodium ions in order to cancel out the negative charges on the RNA caused by the phosphate groups.

Replication

The viral particle binds to cell surface receptors. This causes a conformational change in the viral capsid proteins, and myristic acids are released. These acids form a pore in the cell membrane through which RNA is injected[1]. Once inside the cell, the RNA un-coats and the (+) strand RNA genome is replicated through a double-stranded RNA intermediate that is formed using viral RDRP (RNA-Dependent RNA polymerase). Translation by host cell ribosomes is not initiated by a 5' G cap as usual, but rather is initiated by an IRES (Internal Ribosome Entry Site). The viral lifecycle is very rapid with the whole process of replication being completed on average within 8 hours. However as little as 30 minutes after initial infection, cell protein synthesis declines to almost zero output – essentially the macromolecular synthesis of cell proteins is “shut off”. Over the next 1–2 hours there is a loss of margination of chromatin and homogeneity in the nucleus, before the viral proteins start to be synthesized and a vacuole appears in the cytoplasm close to the nucleus that gradually starts to spread as the time after infection reaches around 3 hours. After this time the cell plasma membrane becomes permeable, at 4–6 hours the virus particles assemble, and can sometimes be seen in the cytoplasm. At around 8 hours the cell is effectively dead and lyses to release the viral particles.

History

In 1897, foot-and-mouth disease virus (FMDV), the first animal virus, was discovered. FMDV is the prototypic member of the Aphthovirus genus in the Picornaviridae family. ^[2] The plaque assay was developed using poliovirus. Both RNA dependent RNA polymerase and polyprotein synthesis were discovered by studying poliovirus infected cells.