Chemoradiotherapy (CRT) improves local and systematic control, time-to-treatment failure and cancer-specific survival compared with radiotherapy (RT) alone in patients with nonresectable rectal cancer, according to a study in the Aug. 1 issue of the Journal of Clinical Oncology.
Morten Brændengen, MD, from the departments of medical oncology and surgery at the Norwegian Radium Hospital and Ullevål University Hospital Cancer Center in Oslo, Norway, and colleagues investigated whether chemotherapy as part of a multidisciplinary treatment approach would improve downstaging, survival and relapse rate.
The randomized study included 207 patients with locally nonresectable T4 primary rectal carcinoma or local recurrence from rectal carcinoma in the period 1996 to 2003, the researchers said. The patients received either chemotherapy administered concurrently with radiotherapy (50 Gy) and adjuvant for 16 weeks after surgery (98 patients), or radiotherapy alone (109 patients).
The researchers performed an R0 resection in 82 patients in the CRT group and in 74 patients in the RT group.
The investigators examined pathologic complete response in 16 percent and 7 percent, respectively. After an R0 + R1 resection, local recurrence was found in 5 percent and 7 percent, and distant metastases in 26 percent and 39 percent, respectively.
According to Brændengen and colleagues, local control (82 vs. 67 percent at five years), time to treatment failure (63 vs. 44 percent), cancer-specific survival (72 vs. 55 percent) and overall survival (66 vs. 53 percent) all favored the CRT group.
The authors wrote that grade 3 or 4 toxicity, mainly GI, was seen in 28 of 98 and six of 109, respectively. However, they said that there was no difference in late toxicity.
"This randomized phase III study confirms that the addition of chemotherapy to radiotherapy improves outcome both concerning local and systemic control," the researchers concluded.
Swedish Cancer Society, Stockholm Cancer Society and the Norwegian Cancer Society supported the trial, along with a regional agreement on medical training and clinical research between Stockholm county council and the Karolinska Institute.