which describes the extent of the primary tumor, lymph node involvement and distant metastases. TNM staging information is contained in pathology reports. Although this system is complicated, it is helpful for determining the extent of cancer and guiding treatment decisions. This article outlines the different stages of colon cancer. In addition, it covers the symptoms associated with each stage. Continue reading to learn more about colon cancer.
In early stage rectal cancer, radiation therapy is not usually administered. It may be used if the cancer has spread and penetrated the rectum’s wall. Most of the side effects of radiation therapy resolve within a few weeks. A physician will first perform a physical examination and ask about any past medical history. During a colonoscopy, the physician inserts a long flexible tube with a camera into the rectum.
During a colonoscopy, a small piece of tissue is removed from the polyp for examination. This sample can be examined under a microscope to confirm whether the polyp is cancerous or not. In advanced stages, colon cancer may have spread to other organs, such as the lungs. PET/CT scans can also identify the presence of metastasis. A blood test called CEA levels can also indicate colon cancer.
While most cases of colon cancer are sporadic, approximately five percent of cases are hereditary. This means that an individual with a hereditary gene mutation is at increased risk for colon cancer and other cancers. Hereditary colon cancer cases typically occur at an earlier age than those with sporadic colon cancer. The risk of developing colon cancer is 50% for males and 50% for females if an affected parent had the disease.
The exact cause of colon cancer is unknown, although certain factors increase the risk. But it is known that genetic changes occur within cells, affecting DNA sequences. Certain genes control how cells divide and grow. Those affected by cancer change their DNA, affecting oncogenes and tumor suppressor genes. The resulting cancerous cells then build up and form a tumor. They can invade other parts of the body and cause further damage.
Most patients have surgery to remove the entire tumor. However, without further treatment, many patients will develop a recurrence of the disease. Fortunately, chemotherapy can help reduce this risk significantly. The type of chemotherapy administered depends on the stage of the tumor, location in the colon, and patient’s tolerance for intensive chemotherapy. Tumors may also be tested for certain markers that indicate their susceptibility to specific treatments. In advanced stages, patients may be given chemotherapy after surgery.
Surgery is the most common treatment for early stage colon cancer. Surgical polypectomy removes a polyp, and a colectomy removes part of the colon and the surrounding tissue. The surgeon may also remove nearby lymph nodes to reduce the risk of spreading the cancer. The surgeon will then reconnect the healthy portion of the colon with the remainder of the colon. When the cancer is removed, a surgeon will then repair the colon and create a stoma to prevent further complication.