Interim analysis of a phase III study on preoperative radiation therapy in resectable rectal carcinoma. Trial of the gastrointestinal tract cancer cooperative group of the European organization for research on treatment of cancer (EORTC)

Abstract

To improve surgical results of potentially operable rectal cancer (T2, T3, T4, Mo), the European Organization for Research on Treatment of Cancer (EORTC) conducted a two‐arm randomized clinical trial to evaluate the effect of administering radiotherapy before radical surgery. Four hundred ten patients were allocated to be treated either by surgery alone or by 34.5 Gy of radiotherapy (in 19 days overall) followed by surgery. The tolerance of the adjuvant radiation therapy was fairly good. The 5‐year survival rate was 65% overall and showed no difference between both therapeutic regimens. Similarly, the metastases‐free rate was the same in both groups. In contrast, the preoperative radiation therapy showed a marked effect on local control of the disease, the comparison of the time to local recurrence being highly significant between the two treatment groups (P = 0.001). The proportion of patients free of local recurrence at 5 years was 85% in the combined treatment versus 65% in the group of patients treated by surgery alone.

A regression analysis of prognostic factors after resection of Dukes' B and C carcinoma of the rectum and rectosigmoid. Does post-operative radiotherapy change the prognosis?

“…Numerous studies using historical controls (Green, 1981;Sichy, 1982;Kopelson, 1983;Hoskins et al, 1985;Tepper et al, 1987) and the randomized study by Gerard et al (1985) have suggested an improved local control after radiotherapy in colorectal cancer. However, the randomized study by the Gastrointestinal Study Group (1985) showed no significant difference in time to tumour recurrence between the radiation plus surgery (50 pts) and the surgery-alone (58 pts) arms.…”

Outcome of Total Pelvic Exenteration for Primary Rectal Cancer

“…Meterissian et al 35 re- ported that adjuvant chemoradiation may significantly improve survival in patients who require pelvic exenteration for the resection of locally advanced rectal carcinoma. However, Gerard et al 36 reported that radiation therapy facilitated local control but did not improve the five-year survival rate over that of surgery alone. This observation may explain why radiation therapy prolongs the time to local recurrence.…”

MRI demonstration of the effect of neoadjuvant radiotherapy on rectal carcinoma

“…Higher rates of tumour regression or downstaging associated with a longer time interval between the end of radiotherapy and surgery have been observed [32,33]. Dahl et al [33] compared their findings of complete tumour regression rate of 4.5% following preoperative radiation dose of 31 Gy with 2.6% regression rate in the EORTC study [34] where the time interval between radiotherapy and surgery was 2 Á3 weeks in the prior study versus median 11 days in the later. We found no correlation between reduction in tumour size and time interval from radiotherapy to surgery for either SCRT or CRT in our study but the number of cases is small.…”