Degree of tumor regression after preoperative chemo-radiotherapy in locally advanced rectal cancer-Preliminary results.

Aim: The aim of this investigation is to determine the degree of tumor regression by histopathological evaluation of surgical specimen after neoadjuvant chemo-radiotherapy for patients with stage IIIB rectal cancer.

Background: The standard therapy for rectal carcinoma is surgical, however, preoperative radiochemotherapy will play an increasing role especially in locally advanced disease. To estimate the prognosis and the effect of radiochemotherapy the postradiochemotherapeutical pathological features are important to assess.