The combination of neoadjuvant chemoradiotherapy and epidermal growth factor receptor inhibitors in the treatment of rectal adenocarcinoma

Abstract

Rectal adenocarcinoma, in contrast to colorectal carcinoma, is typical of its high local reccurence rate. Radiotherapy is proved to reduce the incidence of recurrences. Neoadjuvant chemoradiotherapy demonstrated better treatment results than adjuvant chemoradiotherapy. Standard cytotoxic agents involved in combination therapy are 5- flurouracil or capecitabin. Epidermal growth factor receptor (EGFR) is supposed to play an important role in cell- cycle regulation, proliferation, differentiation, and surviving of normal epithelial tissues. EGFR overexpression in patients with rectal adenocarcinoma is associated with radioresistance of malignant tissues, lower rates of patological complete response after neoadjuvant chemoradiation and generally poor survival. There are many clinical studies describing combination of neoadjuvant chemoradiotherapy with EGFR inhibitors, however, this regimen has not gained an acceptance as a standard of treatmentment.