Neoadjuvant radiochemotherapy for rectal cancer

Neoadjuvant radiochemotherapy has become established treatment for rectal cancer. It is indicated when primary R0 resection is not an option, in cases of higher risk of locoregional relapse following surgical treatment alone, and when initially impossible conservation of the anal sphincter becomes possible in conjunction with neoadjuvant radiochemotherapy. The indication for radiochemotherapy in the upper third of the rectum is still controversial. Reevaluation of the tumor situation following neoadjuvant treatment is necessary before decisions on operative strategy. Modern imaging techniques are limited in this respect, as they hardly allow differentiation between living tumor tissue and lesions. In case of doubt clarity is possible only through surgical exploration, taking R1 resection into account. Overall the recognition of lymph node metastasis is not a sufficient indicator of local relapse. The frequency of postoperative complications following neoadjuvant radiochemotherapy is independent of the operative method. The effect of neoadjuvant radiochemotherapy on long-term survival and formation of distant metastases is still not clarified. Current studies seek clarification through the use of new chemotherapies and modified treatment regimes. Further, the correct time interval between the end of neoadjuvant radiochemotherapy and the following surgical therapy has yet to be determined. This applies also to the management of patients following complete remission.