The Colon Cancer Alliance’s mission is to knock colon cancer out of the top three cancer killers. We are doing this by championing prevention, funding cutting-edge.Colon Cancer: Causes, Symptoms and Treatments. Colon cancer, also known as colorectal cancer, is the second- leading cause of cancer deaths in both men and women. According to the Centers for Disease Control (CDC), 5. Americans died from colon cancer in 2. The disease affects slightly more men than women, and risk increases with age. Sometimes the polyps look like stalks of cauliflower, sometimes they're flat. Richard Goldberg, the physician- in- chief and a professor of medicine at The Ohio State University Comprehensive Cancer Center – James Cancer Hospital and Solove Research Institute. ![]() The colon, or large intestine, is a curving structure that continues the digestion of food from the small intestine, absorbs liquid out of the stool and carries it down to the rectum for elimination. These factors include genetics, diet and health. Individuals with a family history of colon cancer, especially if more than one relative has had the disease, are at increased risk. Also, two genetic syndromes, familial adenomatous polyposis and Lynch syndrome, have been associated with colon cancer. Colon cancer is rare in countries where red meat is less common on the menu. For instance, . Health factors such as obesity, diabetes and lack of exercise are associated with increased risk. Moreover, inflammatory disease such as other types of cancer or conditions such as ulcerative colitis can increase the likelihood of developing colon cancer. As with many cancers, colon cancer develops from the complex interplay of many factors, and no two individuals are the same. Colon polyps are small growths on the inside lining of the colon or rectum. Most colon cancers begin as polyps. Credit: Ross Toro, My. Health. News. Daily Symptoms & screens. Symptoms that may indicate the presence of cancer cells in the colon or rectum include blood in bowel movements, weight loss, stomach pains and constipation or diarrhea. Often, individuals will not experience any symptoms of colon cancer until it has become advanced. For this reason, the U. Colorectal cancer (CRC), also known as bowel cancer and colon cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Colon cancer symptoms can run the gamut from local, such as blood in the stool and constipation, to systemic, such as weight loss and fatigue. Colon cancer — Comprehensive overview covers symptoms, diagnosis and treatment of colon cancers. What are the causes and risk factors of colon cancer? ![]() ![]() S. Preventive Services Task Force recommends that all individuals ages 5. African Americans, who have an increased risk, are advised to begin screening at age 4. American College of Gastroenterology. ![]() The FOBT checks stool samples for blood cells, and should be done annually, the CDC reports. In a Flex Sig, a doctor can look at the bottom third of the colon, unlike a colonoscopy, which includes an examination of the entire colon. It typically doesn’t require sedation. Colonoscopies are generally done under anesthesia, and patients, who are typically groggy after the procedure, often don't return to work that day and will need a ride home. ![]() The colonoscope allows doctors to blow air into the colon, which helps find tumors that may be hiding behind the colon's many wrinkles and folds, Goldberg said. Doctors can also take a biopsy or remove suspicious polyps during the colonoscopy. In other words, earlier stages in which the cancer is small and localized may require less intervention. Typically, surgery can effectively remove small tumors and chemotherapy is prescribed to kill any remaining cells. Chemotherapy drugs commonly used for colon cancer include irinotecan, oxaliplatin, capacitabine and 5- fluorouracil. Often, the remaining colon can be reconnected to the rectum, but if the cancer has also reached the rectum, a colostomy may be needed. In this procedure, a surgeon creates an opening in the abdomen and attaches a colostomy . ![]() Chemotherapy and radiation are then prescribed to kill remaining cancer cells, and control as much as possible the spread of the disease. Alternative treatment. Although there is no scientific evidence to show that alternative treatments can treat or cure colon cancer, certain therapies can improve the quality of life of cancer patients. In addition, exercise and meditation can improve mood and appetite. In fact, daily exercise can improve life outcomes for people with localized colon cancer, according to a 2. International Journal of Cancer. Information on local groups can be found through organizations including the Colon Cancer Alliance, Cancer Care and the American Cancer Society. ![]() With additional reporting by Amber Angelle, My Health News Daily Contributor. Follow Laura Geggel on Twitter @Laura. Geggel and Google+. ![]() Follow Live Science @livescience, Facebook & Google+. Colorectal cancer - Wikipedia. Colorectal cancer. Synonyms. Colon cancer, rectal cancer, bowel cancer. Diagram of the lower gastrointestinal tract. Specialty. Oncology. Symptoms. Blood in the stool, change in bowel movements, weight loss, feeling tired all the time. If a large polyp or tumor is found, a biopsy may be performed to check if it is cancerous. Aspirin and other non- steroidal anti- inflammatory drugs decrease the risk. The classic warning signs include: worsening constipation, blood in the stool, decrease in stool caliber (thickness), loss of appetite, loss of weight, and nausea or vomiting in someone over 5. A number of genetic syndromes are also associated with higher rates of colorectal cancer. The most common of these is hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome) which is present in about 3% of people with colorectal cancer. For people with these syndromes, cancer almost always occurs and makes up 1% of the cancer cases. Colectomy, removal of the colon, may not suffice as a preventative measure because of the high risk of rectal cancer if the rectum remains. A gene that appears to contribute to the potential for metastatic disease, metastasis associated in colon cancer 1 (MACC1), has been isolated. This gene is associated with the proliferation, invasion and scattering of colon cancer cells in cell culture, and tumor growth and metastasis in mice. MACC1 may be a potential target for cancer intervention, but this possibility needs to be confirmed with clinical studies. The mutations can be inherited or acquired, and most probably occur in the intestinal cryptstem cell. The APC protein prevents the accumulation of . Without APC, . These genes are normally important for stem cell renewal and differentiation, but when inappropriately expressed at high levels, they can cause cancer. While APC is mutated in most colon cancers, some cancers have increased . The p. 53 protein, produced by the TP5. Wnt pathway defects. Eventually, a cell line acquires a mutation in the TP5. Sometimes the gene encoding p. BAX is mutated instead. Sometimes TGF- . For example, genes encoding the proteins KRAS, RAF, and PI3. K, which normally stimulate the cell to divide in response to growth factors, can acquire mutations that result in over- activation of cell proliferation. The chronological order of mutations is sometimes important. If a previous APC mutation occurred, a primary KRAS mutation often progresses to cancer rather than a self- limiting hyperplastic or borderline lesion. Progressing through a distinct set of genetic events, hypermutated tumors display mutated forms of ACVR2. A, TGFBR2, MSH3, MSH6, SLC9. A9, TCF7. L2, and BRAF. The common theme among these genes, across both tumor types, is their involvement in WNT and TGF- . Plus a schematic diagram indicating a likely field defect (a region of tissue that precedes and predisposes to the development of cancer) in this colon segment. The diagram indicates sub- clones and sub- sub- clones that were precursors to the tumors. The term . Yet there is evidence that more than 8. Likewise, epigenetic alterations present in tumors may have occurred in pre- neoplastic field defects. An expanded view of field effect has been termed . As described by Vogelstein et al.. The oncogenes and tumor suppressor genes are well studied and are described above under Pathogenesis. However, by comparison, epigenetic alterations in colon cancers are frequent and affect hundreds of genes. For instance, there are types of small RNAs called micro. RNAs that are about 2. These micro. RNAs (or mi. RNAs) do not code for proteins, but they can target protein coding genes and reduce their expression. Expression of these mi. RNAs can be epigenetically altered. As one example, the epigenetic alteration consisting of Cp. G island methylation of the DNA sequence encoding mi. R- 1. 37 reduces its expression. This is a frequent early epigenetic event in colorectal carcinogenesis, occurring in 8. The altered adjacent tissues associated with these cancers are called field defects. Silencing of mi. R- 1. RNA. Other micro. RNAs, with likely comparable numbers of target genes, are even more frequently epigenetically altered in colonic field defects and in the colon cancers that arise from them. These include mi. R- 1. 24a, mi. R- 3. R- 3. 42 which are silenced by Cp. G island methylation of their encoding DNA sequences in primary tumors at rates of 9. Of the hypermethylated genes, 1. Disease extent is usually determined by a CT scan of the chest, abdomen and pelvis. Other potential imaging tests such as PET and MRI may be used in certain cases. Colon cancer staging is done next, based on the TNM system which considers how much the initial tumor has spread, if and where lymph nodes are involved and the extent of metastatis. A pathology report usually contains a description of cell type and grade. The most common colon cancer cell type is adenocarcinoma (9. This very rarely causes obstruction of feces, and presents with symptoms such as anemia. Left- sided tumors tend to be circumferential, and can obstruct the bowel lumen, much like a napkin ring, and results in thinner caliber stools. Microscopy. It invades the wall, infiltrating the muscularis mucosae layer, the submucosa, and then the muscularis propria. Tumor cells describe irregular tubular structures, harboring pluristratification, multiple lumens, reduced stroma (. Sometimes, tumor cells are discohesive and secrete mucus, which invades the interstitium producing large pools of mucus. This occurs in mucinous adenocarcinoma, in which cells are poorly differentiated. If the mucus remains inside the tumor cell, it pushes the nucleus at the periphery, this occurs in . Besides the primary tumor a lot of lesions can be seen. On cursor position: lung nodule. Fungating carcinoma of the colon. Micrographs (H& E stain)Cancer — Invasive adenocarcinoma (the most common type of colorectal cancer). The cancerous cells are seen in the center and at the bottom right of the image (blue). Near normal colon- lining cells are seen at the top right of the image. Cancer — Histopathologic image of colonic carcinoid. Precancer — Tubular adenoma (left of image), a type of colonic polyp and a precursor of colorectal cancer. Normal colorectal mucosa is seen on the right. Staging. The Astler- Coller classification (1. Dukes classification (1. The T stages of bowel cancer. Dukes stage A bowel cancer; the cancer is only in the inner lining of the bowel. Dukes stage B bowel cancer; the cancer has invaded the muscle. Dukes stage C bowel cancer; the cancer has invaded the nearby lymph nodes. Dukes stage D bowel cancer; the cancer has metastasized. The most common metastasis sites for colorectal cancer are the liver, the lung and the peritoneum. It has been postulated to represent an epithelial–mesenchymal transition (EMT). Tumor budding is a well- established independent marker of a potentially poor outcome in colorectal carcinoma that may allow for dividing people into risk categories more meaningful than those defined by TNM staging, and also potentially guide treatment decisions, especially in T1 and T3 N0 (Stage II, Dukes’ B) colorectal carcinoma. Unfortunately, its universal acceptance as a reportable factor has been held back by a lack of definitional uniformity with respect to both qualitative and quantitative aspects of tumor budding. The risk is not negated by regular exercise, though it is lowered. Screening has the potential to reduce colorectal cancer deaths by 6. Annual to biennial FOBT screening reduces colorectal cancer mortality by 1. A positive result should be followed by colonoscopy. If used, screening is recommended every 3 years, starting at age 5. For those at high risk, screenings usually begin at around 4. Examples of countries with organised screening include the United Kingdom. The decision on which aim to adopt depends on various factors, including the person's health and preferences, as well as the stage of the tumor. However, when it is detected at later stages (for which metastases are present), this is less likely and treatment is often directed at palliation, to relieve symptoms caused by the tumour and keep the person as comfortable as possible. This can either be done by an open laparotomy or sometimes laparoscopically. Sometimes chemotherapy is used before surgery to shrink the cancer before attempting to remove it. The two most common sites of recurrence of colorectal cancer are the liver and lungs. The decision to add chemotherapy in management of colon and rectal cancer depends on the stage of the disease. In Stage I colon cancer, no chemotherapy is offered, and surgery is the definitive treatment. The role of chemotherapy in Stage II colon cancer is debatable, and is usually not offered unless risk factors such as T4 tumor or inadequate lymph node sampling is identified. It is also known that the patients who carry abnormalities of the mismatch repair genes do not benefit from chemotherapy. For stage III and Stage IV colon cancer, chemotherapy is an integral part of treatment. If the lymph nodes do not contain cancer, the benefits of chemotherapy are controversial. If the cancer is widely metastatic or unresectable, treatment is then palliative. Typically in this setting, a number of different chemotherapy medications may be used. Some specific regimens used for CRC are FOLFOX, FOLFOXIRI, and FOLFIRI. Another class of drugs used in the second line setting are epidermal growth factor receptor inhibitors, of which the two FDA approved ones are cetuximab and panitumumab. Often, it is used in conjunction with chemotherapy in a neoadjuvant fashion to enable surgical resection, so that ultimately as colostomy is not required. However, it may not be possible in low lying tumors, in which case, a permanent colostomy may be required. Stage IV rectal cancer is treated similar to stage IV colon cancer. Radiation therapy.
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