Rectal Cancer (cont.)

The treatment and prognosis of rectal cancer depend on the stage of the cancer, which is determined by the following 3 considerations:

• How deeply the tumor has invaded the wall of the rectum
  
  
• Whether the lymph nodes appear to have cancer in them
  
  
• Whether the cancer has spread to any other locations in the body(Organs that rectal cancer commonly spreads to include the liver and the lungs.)

The stages of rectal cancer are as follows:

• Stage I: The tumor involves only the first or second layer of the rectal wall and no lymph nodes are involved.
  
  
• Stage II: The tumor penetrates into the mesorectum, but no lymph nodes are involved.
  
  
• Stage III: Regardless of how deeply the tumor penetrates, the lymph nodes are involved with the cancer.
  
  
• Stage IV: Convincing evidence of the cancer exists in other parts of the body, outside of the rectal area.

Localized rectal cancer includes stagesI-III. Metastatic rectal cancer is stage IV.

The goals of treating localized rectal cancer are to ensure the removal of all the cancer and to prevent a recurrence of the cancer, either near the rectum or elsewhere in the body.

If stage I rectal cancer is diagnosed, then surgery is likely to be the only necessary step in treatment.The risk of the cancer coming back after surgery is low, and, therefore, chemotherapy is not usually offered.

Sometimes, after the removal of a tumor, the doctor discovers that the tumor penetrated into the mesorectum (stage II) or that the lymph nodes contained cancer cells (stageIII).In these cases, chemotherapy and radiation therapy are offered after recovery from the surgery to reduce the chance of the cancer returning.Chemotherapy and radiation therapy given after surgery is called adjuvant therapy.

If the initial exams and tests show a person to have stage II or III rectal cancer, then chemotherapy and radiation therapy should be considered before surgery. Chemotherapy and radiation given before surgery is called neoadjuvant therapy. This therapy lasts approximately 6 weeks.Neoadjuvant therapy is performed to shrink the tumor so it can be more completely removed by surgery.In addition, a person is likely to tolerate the side effects of combined chemotherapy and radiation therapy better if this therapy is administered before surgery rather than afterward.Afterrecovery from the surgery, a person who has undergone neoadjuvant therapy should meet withtheoncologist to discuss the need for more chemotherapy.

If the rectal cancer is metastatic, then surgery and radiation therapy would only be performed if persistent bleeding or bowel obstruction from the rectal mass exist. Otherwise, chemotherapy alone is the standard treatment of metastatic rectal cancer.At this time, metastatic rectal cancer is not curable.However, average survival times for people with metastatic rectal cancer have lengthened over the past several years because of the introduction of new medications.