Preoperative Radiotherapy for colorectal Cancer

Abstract

In a prospective randomized trial, 700 patients with a confirmed histological diagnosis of adenocarcinoma of the rectum or rectosigmoid were randomized to receive radiotherapy prior to operation (2000 to 2500 rads in two weeks) or surgery alone. Five year observed survival in the 453 patients on whom "curative" resection was possible was 48.5% in the X-ray treated group compared with 38.8% in controls, while in the 305 having low lying lesions requiring abdominoperineal resection, survival in the treated group was 46.9% compared with 34.3% in controls. Although suggestive of a treatment benefit, neither is considered statistically significant. Histologically positive lymph nodes were found in 41.2% of the control group and in only 27.8% of the patients receiving radiotherapy. Reveiw of all patients who died during the study shows a consistently lower death rate from cancer in the radiotherapy group. Although this study suggests a treatment benefit from preoperative radiotherapy, further studies now in progress by this group and others are necessary to determine the optimal dose regimen.

The rationale to switch from postoperative hyperfractionated accelerated radiotherapy to preoperative hyperfractionated accelerated radiotherapy in rectal cancer

“…The dose increment between trial 89-02 and trial 91-9 1 was in accordance to the dose response data obtained by an extensive review of the literature (15,20,21,32,35,37,40,42). Low-dose radiotherapy has no significant effect on local control (20,32,37,40), whereas doses higher than 20 Gy seem to significantly affect local recurrence rate (15,42). It is interesting to note that both in the Stockholm Trial and in the EORTC 40761 trial there is a positive impact of radiation on pelvic control.…”

Two initiation sites of early detection of colon cancer, revealed by localization of pERK1/2 in the nuclei or in aggregates at the perinuclear region of tumor cells

“…Colorectal cancer is the second leading cause of cancer deaths in Western countries (1). Despite of more than two decades of research into the molecular genetics of colon cancer, there is a lack of prognostic and productive molecular biomarkers with proven utility in this setting (reviewed in refs.…”

“…Despite of more than two decades of research into the molecular genetics of colon cancer, there is a lack of prognostic and productive molecular biomarkers with proven utility in this setting (reviewed in refs. [1][2][3]. It was suggested that balance between MAPK pathways could be critical for presenting or promoting growth in a variety of cancer cell lines, including colon cancer cell lines (2).…”

Adjuvant Therapy on Cancer of the Lower Rectum. Evaluation of the Effects of Preoperative Radiotherapy on the Prognosis of Patients with Cancer of the Lower Rectum

“…Preoperative irradiation for cancer of the lower rectum has been the object of controversies, specially when survival is discussed [2,5,8,9,11,13,[15][16][17][18]20,21,[24][25][26][27][30][31][32][33][34][36][37][38][39] and only a very few randomized statistic papers are able to demonstrate better long-term results [28,35]. Recurrence, especially local recurrence, is responsible for the great majority of deaths in the first two years after surgery [1,7,19].…”