ADVANCING THE TREATMENT OF RECTAL CANCER: Sphincter-Sparing Surgery Improves Quality of Life
More than 40,000 cases of rectal cancer are diagnosed in the United States each year, and each year it claims thousands of lives. Together with the cancer incidence of the rest of the large intestine (colon), of which the rectum forms the last 10 to 12 cm (about 4-5 inches), colorectal cancer is the second-leading cause of cancer-related deaths in the country. Only lung cancer kills more people.
The good news is that new methods for treating rectal cancer have evolved in recent years from clinical trials performed worldwide, with outcomes that show reduced recurrence rates and better survival. At Stony Brook, our surgical oncologists are providing the treatments based on these trials in an effort to significantly improve outcomes in patients with rectal cancer.
"The number of rectal cancer patients being diagnosed and treated at University Hospital is increasing and our gastrointestinal cancer team is now routinely offering these treatment methods to their patients with rectal cancer," says Martin S. Karpeh, Jr., MD, professor of surgery and chief of surgical oncology.
Patients are also being asked to enroll in various clinical trials for rectal cancer. These trials are aimed at improving the effect of radiation, chemotherapy, and surgery in the management of this devastating disease.
Dr. Karpeh says that by applying newer treatment strategies based on the results of well-designed clinical trials, patients with rectal cancer treated here at Stony Brook will benefit from the latest worldwide treatment advancements.
Rectal cancers involving the lower third of the rectum are traditionally treated by surgical removal of the rectum and anus, leaving the patient with a permanent colostomy bag. The first new treatment approach used in the trials and incorporated at Stony Brook involves the use of combined radiation and chemotherapy before the patient has surgery. This approach appears to reduce the risk of disease recurrence.
The second advance has to do with the way the operation is performed. Using sharp dissection, the surgeon removes tumors outside the investing layer of tissue of the rectum (mesorectum) without breaking it, thus lowering the risk of leaving cancer cells behind in the pelvis.
Our colorectal specialists, Marvin L. Corman, MD, professor of surgery, and David E. Rivadeneira, MD, assistant professor of surgery, both of our Division of Surgical Oncology, perform sphincter-sparing surgery to treat rectal cancer.
"In selected cases the use of less invasive laparoscopic techniques minimizes postoperative recovery without compromising the cancer operation," says Dr. Karpeh. He emphasizes that an added advantage of the preoperative combination of radiation and chemotherapy is that it increases the chances that the anal sphincter muscle can be spared, greatly reducing the chances of the patient having a permanent colostomy.
The sphincter of the anus is the circular muscle that controls defecation. If damaged, patients lose control of bowel function.
The standard surgical procedure used to remove rectal cancer that lies close to the anus is the abdominoperineal resection, in which the anus is removed with the rectum, and the cut end of the large bowel is then attached to the abdominal wall to form a colostomy. The colostomy is covered by a replaceable bag that collects stool as it empties from the bowel.
Sphincter-sparing surgery allows the patient to preserve function of the anus. Sphincter-sparing treatment for stage I rectal cancer involves the limited surgery described above to remove the cancer and a small rim of normal bowel, but not the anus.
PARTICIPATING IN WORLDWIDE TRIALS
The first clinical trial with large numbers of patients that showed significant improvement in reducing recurrence of resectable rectal cancer and increasing five-year survival rates was reported in 1997 in Sweden. In this study of more than 1,000 patients, the recurrence rate after five years for those who received radiotherapy before surgery was 11%. For those who had surgery alone, the recurrence rate was much higher at 27%.
The overall five-year survival rate for those who had radiotherapy pre-surgery was 58%, compared to 48% for the surgery alone group. Another study, reported in 2001 in the Netherlands, followed more than 1,800 rectal cancer patients who were randomly assigned to two treatment groups-one in which patients had preoperative radiotherapy followed by surgical excision, and the other group that had surgical excision alone. After two years, the survival rates were nearly the same between the two groups, 82% for those who had both forms of therapy and 81.8% for those who had excision alone.
The rate of recurrence at two years, however, was significantly higher in the surgery alone group (8.2%) compared to the radiotherapy plus surgery group (2.4%) in spite of the high quality of surgery performed in this trial.
More recently, similar patient outcomes have resulted in comparative trials done in other countries, such as Italy and Canada. One study reported that an overview of more than 8,500 rectal cancer patients from 22 randomized trials indicated that shorter courses of preoperative radiation appear to be at least as effective as longer schedules.
Dr. Karpeh says that our multidisciplinary gastrointestinal cancer clinical team expects to continue participating in national and international clinical trials that focus on the preoperative use of combination radiation and chemotherapy treatment to increase the amount of sphincter-sparing surgery for rectal cancers.
These trials may help to further reduce disease recurrence and improve survival rates for Long Islanders with rectal cancer.
For consultations/appointments with our colorectal surgeons — Dr. Marvin L. Corman and Dr. David E. Rivadeneira — please call 631-444-4545.
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