Such a conservative approach is receiving a growing interest all over the world among colorectal cancer specialists. The extensive and pioneering work of Prof. Habr Gama in Brazil is presently considered as a reference for the use chemoradiotherapy and an EBRT boost (total dose 54 Gy/30 f/6 weeks) followed by watch and wait in case of cCR to preserve organ, i.E. to avoid surgery.