The colon and rectum are parts of the gastrointestinal system.
Most colon cancers are adenocarcinomas. They arise from the inner cell lining of the large bowel.
A cell growth on the surface of the colon is called polyp. A polyp may turn into cancer, especially if increases in size.
Adenocarcinomas represent 95% of colon cancer cases.
Other types of malignancies (the remaining 5%) are:
- GIST (gastrointestinal stromal tumor), derived from the muscle layer of the colon and create a kind of Gastrointestinal “sarcoma”.
- Lymphoma: cancer derived from the immune system cells (lymphocytes) found in the lymphatic tissue of bowel’s mucosa.
- Carcinoids: malignancies of the neuroendocrine cells scattered in the mucosa of the gastrointestinal tract. They usually do not cause symptoms.
Symptoms of colon cancer
- Changes in the bowel habits (constipation, diarrhea or change in stool consistency)
- Rectal bleeding or blood mixed in stool
- Abdominal pain, bloating, cramps
- Feeling of incomplete bowel evacuation
- Unexplained fatigue
- Loss of appetite
- Unexplained weight loss
- Unexplained anemia
Risk factors for developing cancer
- Age (usually> 50 years)
- Nutrition (rich in red meat, low in fiber)
- History of colon polyps
- Family history of cancer or polyposis
- inflammatory bowel diseases (Crohn disease, ulcerative colitis)
- Hereditary syndromes (familial adenomatous polyposis, hereditary non-polypoid colorectal cancer)
- Consumption of alcohol, tobacco
- Diabetes Type II
(These tests are used for diagnosis and staging of colon cancer in order to decide the appropriate treatment)
- Digital rectal examination
- CT (C / T) and magnetic (MRI) of the abdomen
- Barium enema
The Treatment for the colorectal cancer is based on the tumor location, tumor size and its spread to lymph nodes or to other organs.
A colectomy is the operation usually performed. It consists of the surgical resection of any extent of the large bowel. When the resection is complete, the surgeon has the option of immediately restoring the bowel, by stitching together both the cut ends (anastomosis).
Depending on the stage, the patient may receive adjuvant chemotherapy. Chemotherapy keeps cancer from spreading, slows its growth, or destroys cancer cells that have spread to other parts of the body.
Radiotherapy is a regional treatment. It may be given before surgery to shrink a tumor or after surgery to kill the cancer cells that may remain. It can also be given before, during or after chemotherapy or hormone treatment to improve overall results.
Palliative treatment aims to shrink tumours and reduce pain or relieve other cancer symptoms. Palliative radiotherapy may also prolong life.