Anal Cancer Treatment Options

When performed, surgical resection usually is an abdominal perineal resection (APR), which consists of a wide excision of the anus, including the anal muscles, with placement of a permanent colostomy. A colostomy is performed by connecting the bowel to a hole in the abdominal wall (called a stoma). The stool that passes through the stoma is collected in a bag that is attached to the outside of the abdominal wall with adhesive. This bag can then be emptied by the patient as needed. Because the combination of chemotherapy and radiation therapy result in similar rates of local control and survival when compared to surgery, chemoradiation has been favored over surgery because it offers patients a good chance at preserving anal sphincter function, avoiding the need to place a permanent colostomy.

Surgical Options. There are several situations in which surgery should be considered for anal cancer. Patients with carcinoma in situ or small, well-differentiated anal cancers that have not invaded into the anal sphincter can sometimes undergo a surgical excision without removing the anal muscles. In these early cases, the results of surgical excision can be quite good, and the patient can be spared to potential side effects of chemoradiotherapy. Alternatively, extensive anal cancers that have destroyed the anal sphincter, such that the patient cannot control bowel movements, are often treated with an APR. In these cases, patients have already lost their sphincter function, and require a colostomy to handle bowel movements. In these cases, surgical resection is often performed, and radiation with or without chemotherapy is given post-operatively. Surgery can also be performed in patients who cannot otherwise tolerate radiation therapy. Finally, surgery is often performed in the case of a local recurrence following previous treatment with radiation therapy if additional chemotherapy and radiation cannot be given.

Anal cancers can take some time to respond to treatment and often continue to shrink months after chemotherapy and radiation have ended. Therefore, it is not unusual to have a residual mass immediately after treatment. The presence of a residual mass does not mean that the treatment did not work.

Radiation Therapy. This therapy has become the mainstay in the treatment of anal cancer. Its goal is to kill cancer cells while harming as little normal tissue as possible. Radiation therapy may be used before, during and/or after chemotherapy, and is delivered in one of two ways depending on the type and stage of cancer being treated: either to the affected area(s) from outside the body or inserted through a needle or catheter into or near the cancer.

Chemotherapy. This treatment uses potent drugs to eradicate, shrink, slow the growth of or prevent cancer from spreading. The way the chemotherapy is given depends on the type and stage of the cancer being treated. Typically, a combination of drugs is administered intravenously (directly into the veins) in a series of treatments over a period of weeks or months, with breaks in-between so that the patient’s body can recover. With anal cancer, chemotherapy is most commonly given at the same time as radiation.

Chemoradiotherapy. Chemotherapy has been shown to be radiosensitizing when given at the same time as radiation therapy. This means that the effect of the radiation is increased when given together with chemotherapy. Several large trials have shown that local control of the tumor is significantly improved when chemoradiotherapy is used compared to radiation alone. However despite this improvement in local control of the tumor, no difference in overall survival has been seen with combined modality therapy compared to radiation alone. Regardless, combined modality therapy is now the standard treatment for most patients with anal cancer, unless the patient is unable to tolerate combined treatment.

Seek the most aggressive treatments available from our Multidisciplinary GI Clinic with a referral from your primary care physician or with a self-referral by calling 1-877-LACKS-MI or 616-752-LACK(S).