Getting chemo first may help in rectal cancer

(Medical Xpress)—A new phase II study to be presented at the annual meeting of the American Society for Clinical Oncology finds that if chemotherapy is offered before radiation and surgery, more patients will be able to tolerate it and receive a full regimen of treatment.

First things first. If cancer patients are having trouble tolerating chemotherapy after chemoradiation and surgery, then try administering it beforehand. Reordering the regimen that way enabled all but six of 39 patients to undergo a full course of standard treatment for rectal cancer, according to research to be presented at the American Society for Clinical Oncology annual meeting in Chicago.

Studies have shown that only about 60 percent of rectal cancer patients comply with postoperative chemotherapy, said lead researcher Dr. Kimberly Perez, assistant professor of medicine in the Warren Alpert Medical School of Brown University and a cancer physician at Rhode Island Hospital. In the phase II trial, "Complete Neoadjuvant Therapy in Rectal Cancer" (CONTRE), more than 90 percent of the patients were able to complete a regimen of mFOLFOX6 when it was moved to the front of the line.

"The thought was, what can we do to make it more tolerable and get the benefit that we wanted," said Perez, who will speak at 4 p.m. CDT on Saturday, May 31, 2014 at ASCO.

"It's encouraging because we were able to get the numbers up of patients who were able to get all the chemotherapy indicated."

All but one patient in the study underwent surgery and 85 percent underwent the middle step of chemoradiation after completing chemotherapy. The vast majority therefore received all three courses of standard treatment, albeit in a new order.

Almost all of the patients came into the study with rectal bleeding, but that symptom abated for all of them during treatment, Perez said.

Regarding the cancer itself, a majority of patients, 32 of whom entered the trial at stage III and seven of whom were less advanced at stage II, responded at least to some degree to the induction chemotherapy and chemoradiation treatments. By the time they got to surgery, 13 patients had no tumor left ("pathologic complete response"), 10 got all they way back to stage I, seven were at stage II, and eight remained at stage III.

The study occurred too recently, however, to provide a measure of overall survival, Perez acknowledged. The last patient finished surgery in January 2014.

The rate of side effects such as neutropenia, an adverse impact on the immune system, was not unusual.

The results of the CONTRE trial are now feeding into the development of a new national rectal cancer trial spearheaded by NRG Oncology, Perez said. That protocol will involve chemo first, then chemoradiation with biological anti-cancer agents, and finally surgery. Brown Univeristy Oncology Group and the Cancer Center of Rhode Island Hospital and associated satellites will be one of the study sites, Perez said.