The definition of colon cancer is “cancer that forms in the tissues of the colon, which is the longest part of the large intestine.” Most often, a colon cancer cell is responsible for making and releasing mucus and other fluids, so it’s very easy to pass on to surrounding tissues. This type of cancer is called an adenocarcinoma. This cancer progresses slowly over the years, through five different stages, which can often be detected through screening colonoscopy procedures.
With colon cancer, the initial stage, which is Stage 0, is found in the epithelial tissue of the innermost lining of the colon. Here, doctors find cells that are abnormal but have not yet mobilized into full-blown cancer. To treat this stage, doctors will perform a polypectomy, which is a local excision to remove the tumor and surrounding tissue. This treatment is usually considered curative and often no further problems develop if caught early during colon cancer screening tests. In Stage I, the cancer has spread beyond the innermost layer to the second and third layers, as well as the inside wall of the colon. According to the National Cancer Institute’s most recent data (1991 to 2000), there is a 93% survival rate for colon cancer patients with Stage I cancer.
During Stage II of colon cancer, the tumors have evolved past the middle layers of the colon to the tissues around the rectum and outermost colon layers (II-A) and beyond the thick, muscular colon wall into nearby organs like the bowels, bladder, uterus or prostate (II-B). The survival rate for II-A is 85% and 72% for II-B. After that, the carcinoid tumors may spread to infect three nearby lymph nodes, which are normally used to fight off invaders (III-A). They may also infect three lymph nodes, nearby colorectal tissue and the entire colon wall (III-B) or to four or more lymph nodes, surrounding tissues, the colon wall and nearby organs (III-C). Patients at Stage III-A have an 83% survival rate, III-B have a 64% survival rate and the more serious III-C have just a 44% survival rate.
Colon cancer treatment is best done if caught early. Often Stage 0 and Stage I cancers can be treated using a colonoscope during a routine colonoscopy, removing small colon polyps or abnormal cells. If there are larger clusters of abnormal cells, then they may be removed through minimally invasive laparoscopic surgery, which involves a few minor incisions and a very short hospital stay. These procedures have seen vast improvements are very effective at removing early stage cancer. In later stages, if the surgery cannot simply remove the affected tumors or cells, then entire portions of the colon must be removed. In the past, patients of colon cancer in the advanced stages would need to wear a bag that collected their waste. Yet today, the colon can often be connected directly to the rectum to get rid of waste more naturally. In rare cases, a bag will still need to be implanted. Chemotherapy and radiation therapy are usually given during the more serious surgeries.