The "Watch and wait" approach following chemoradiotherapy for rectal cancer: a case series and review of literature.

Neoadjuvant chemoradiotherapy (NCRT) combined with total mesorectal excision (TME) is currently the gold standard for locally advanced low-lying rectal cancer (LACR). Around 20-30% of patients after NCRT can achieve clinical complete response (cCR); 5-44% of the patients who underwent TME achieve pathological complete response (pCR) on postoperative histopathologic studies. In the present study we perform a review of current Literature and retrospectively analyze our personal experience on and approach after cCR. Further studies are needed to establish an internationally accepted definition of clinical complete response, to delineate the real role of MRI in the post-treatment staging and to determine more precise predictors of sustained clinical complete response. The eventual presence of long-term morbidity and adverse effects after chemoradiation needs as well to be better evaluated. Evidence suggests that watch and wait approach is associated with substantially better quality of life and functional outcomes compared with standard surgical resection. KEY WORDS: Chemoradiation, Neoadjuvant therapy, Rectal cancer, Remission induction.