BOSTON – Good results come to those who wait, suggest the findings of a study of optimal timing of surgical decisions in patients with advanced stage cancers in the distal rectum.
When surgeons waited 8 to 12 weeks after the completion of neoadjuvant chemoradiation to decide whether to proceed with radical sphincter preservation surgery (SPS) or abdominoperineal resection (APR) in patients with T3 cancers of the distal third of the rectum, they were able to avoid creating a colostomy with no adverse oncologic outcomes in 79% of patients, reported Dr. Elizabeth A. Myers and her colleagues from the Lankenau Medical Center and Institute for Medical Research in Wynnewood, Pennsylvania.
“An interesting thing, but still quite controversial, is the timing of when you do surgery,” Dr. Myers said in an interview during a poster session at the annual Society of Surgical Oncology Cancer Symposium.
“There is a large school of thought that still believes you should base your surgical plan on the tumor at its presentation, versus making the decision once the patient has undergone neoadjuvant chemoradiation treatment. The purpose of our study is to show with our data that you can safely alter your decision making based on what the cancer presents as following neoadjuvant chemoradiation,” she said.
The investigators looked at 192 consecutive patients with T3 cancers of the distal third of the rectum who were included in a prospectively maintained database. At the time of presentation, all of the patients would have met criteria for requiring APR and colostomy, due to unfavorable factors for pelvic surgery such as prior radiation (97%), male sex (68%), preoperative fixed tumor (59%), or obesity (23%).
The patients underwent neoadjuvant radiation given at a mean of dose of 5,580 cGy, consisting of a 4,500 cGy standard dose and a 1,080 cGy boost to the area of tumor. Most (87%) also received concurrent 5-fluorauracil-based chemotherapy.
“We have found that this helps to downgrade the tumor quite well,” Dr. Myers said.
Following the completion of therapy, they waited for 8 to 12 additional weeks before planning surgery to allow for the maximum benefit of radiation.
All patients, except those who at the end of neoadjuvant chemotherapy still had a fixed cancer at the 3 cm level or below, were offered SPS. The mean time from completion of chemotherapy to surgery was 11 weeks.
Of the 192 patients, 41 underwent APR, 109 had radical SPS, including 107 receiving transanal transabdominal proctocolectomy with coloanal anastomosis (TATA), and 2 receiving low anterior resection. The remaining patients had local excision with either a transanal technique (TAE; 15 patients) or transanal endoscopic microsurgery (TEM, 27 patients).
After a mean follow-up of 55.4 months (range, 1-242 months) the 5-year stoma-free survival rate was 79%. Kaplan-Meier 5-year actuarial survival rates were 98% for all patients who underwent radical SPS, 100% for those who had local excision with TEM, 82% for those who had local excision with TAE (combined SPS procedures, 95%), and 72% for patients who underwent APR.
Local recurrences occurred in 6.6% of all patients who underwent SPS, compared with 7.3% of those who underwent APR. Distant metastases occurred in 22.5% and 24.4%, respectively.
“Holding surgical decision-making until after completion of neoadjuvant therapy allows for increased sphincter preservation with good oncologic outcomes in rectal cancer patients,” the investigators concluded.