The most common sites of metastasis for rectal cancer include the liver, lung and ovaries, says the National Cancer Institute. Rectal cancer that has metastasized to other organs, such as the liver, is classified as stage IV rectal cancer and is considered incurable. While the disease is not able to be fully eradicated, treatments are available to minimize pain or discomfort, shrink existing tumors, slow down cancer progression and improve quality of life.
Surgery
According to the National Cancer Institute, surgery for stage IV rectal cancer is typically resection, which involves removing the cancerous part of the rectum or the entire rectum, depending on how widespread the cancer is in the organ. Prior to surgery, chemotherapy or radiation may be given to help shrink the cancer and make it less difficult to remove. Pelvic exenteration is another surgical option, states the National Cancer Institute. This procedure removes the lower colon, rectum and bladder, and creates openings for urine and stool to leave the body. In women, the ovaries, cervix and vagina may be removed, along with pelvic lymph nodes. A stent may also be surgically placed in the rectum to keep it open, if tumors are threatening to block it.
Chemotherapy
Chemotherapy is the use of drugs to kill cancer cells; it is used in the treatment of metastasized rectal cancer, typically in conjunction with other treatments like radiation or surgery. It may be given prior to, or after, surgery, and may be used palliatively to relieve any pain that tumors may be causing. According to the American Cancer Society, advanced rectal cancer that is not symptomatic is usually treated with chemotherapy. Commonly used regimens listed by the American Cancer Society include FOLFOX, which uses the drugs leucovorin, 5-FU and oxaliplatin; FOLFIRI, which consists of leucovorin, 5-FU and irinotecan; CapOX, which is capecitabine and oxaliplatin; and irinotecan, with or without cetuximab. Side effects of chemotherapy can include lowered white and red blood cell counts, which can lead to anemia and increased risk of infection; fatigue; mouth sores; nausea or vomiting; and loss of appetite.
Radiation
The National Cancer Institute states that for rectal cancer that has metastasized to the liver, internal radiation therapy may be used. Internal radiation therapy, or brachytherapy, involves the placement of radioactive seeds or pellets near the tumor to help kill cancer cells. This helps limit the exposure of healthy tissue to radiation. Side effects may include fatigue, rectal or bladder irritation, bowel incontinence, nausea and sexual problems, according to the American Cancer Society.
Clinical Trials
Clinical trials are closely monitored research studies that study whether new treatments are more effective than the current standard treatments for different diseases. A patient can leave a trial at any time with no repercussions to his care, and participation in a clinical trial may be an option for some patients with metastatic rectal cancer. For information about possible clinical trial participation, a patient should talk to his oncologist about whether this is a viable treatment option.
