LISBON, PortugalShort-term preoperative radiotherapy significantly lowers the risk of local recurrence in patients with rectal cancer who undergo standardized total mesorectal excision (TME), Cornelis J.H. van de Velde, MD, PhD, reported at the 11th European Cancer Conference (ECCO abstract 143). Dr. van de Velde, a University of Leiden surgeon, chairs the Dutch Colorectal Cancer Group.
Standardization and quality control were important foundations of the TME study. Dr. van de Velde reminded the audience that the 1997 Swedish Rectal Cancer Study, the first trial to establish the survival benefit of preoperative radiotherapy, documented a 27% local recurrence rate among patients treated with surgery alone.
In contrast, he emphasized, recurrence rates of only 10% have been reported following standardized, good anatomical surgery in which the circumferential margins are removed. So, the key question addressed by the TME trial was whether preoperative radiotherapy can enhance local control even after optimal surgical resection.
To achieve standardization in the TME study, participating surgeons were required to perform five operations under the supervision of an "instructor surgeon" from another hospital before they were allowed to enter patients into the trial. Surgery quality-control priorities included nerve preservation, pouch anastomosis, and the avoidance of stomas by performing low anterior resections. Pathology standards were also instituted.
The study investigators randomly assigned 1,861 patients with resectable rectal cancer to receive radiotherapy, 5 Gy per day for 5 days, followed by TME a week later, or to undergo TME without radiation therapy.
Combining preoperative radiotherapy with TME reduced the 2-year local recurrence rate to 2.4%, compared with 8.2% among patients who underwent surgery alone (P < .001). No difference in overall survival has yet become apparent, Dr. van de Velde said.