Treatment options vary depending on the stage of the cancer at the time of diagnosis, although surgery has the highest cure rates for this type of cancer. There is no standard therapy for patients with widespread metastasis. Chemotherapy is used for adjuvant therapy and with recurrence or metastatic colon cancer. The most common type of chemotherapy used is agent 5-Fluorouracil (5-FU) combined with Leucovorin (LV). Radiation can be used as preoperative and/or postoperative treatment for rectal cancer. The optimal sequence of surgery, irradiation and chemotherapy is not known, and is the subject of many ongoing clinical trials.
Listed below are the different stages of the disease, along with treatment options available for each stage.
Stage 0 – Tumor has not invaded any surrounding tissue, carcinoma in a polyp or adenoma, non invasive. Most colorectal cancers appear to arise in polyps. Treatment includes local tumor destruction, which may include cryosurgery, fulguration, laser surgery or electrocautery.
Stage I – Tumor is localized and invasion is confined to colon. Treatment includes local excision and may include endoscopic snare, excisional laser surgery, or polypectomy.
Stage II – Tumor has invaded surrounding tissue by direct extension only, extension through abdominal wall to other organs. Treatment may include wedge resection, segmental resection or partial resection of a colonic flexure. Postoperative radiation therapy may be useful as well.
Stage III– Tumor is present in regional lymph nodes of primary site only. Treatment includes adjuvant chemotherapy and surgery. Postoperative radiation therapy may be useful as well.
Stage IV – Tumor is present and has invaded through adjacent tissue to surrounding organs by direct extension and lymph nodes are involved. Treatment may involve palliative chemotherapy, radiation, or surgery to relieve obstruction. There is no proven curative therapy for stage IV disease.