Short-Course Radiotherapy versus Long-Course Radio-Chemotherapy as Neoadjuvant Treatment for Locally Advanced Rectal Cancer: Meta-Analysis from a Toxicity Perspective.

Neoadjuvant treatment has become the standard of care for locally advanced rectal cancer for many years. Several neoadjuvant therapeutic options are currently used, the most common being conventionally fractionated radiotherapy (or long-course radiotherapy) administered concomitantly with chemotherapy and hypofractionated radiotherapy (or short-course radiotherapy). This meta-analysis will give a better overview of the results of several studies that compare long-course radio-chemotherapy with short-course radiotherapy, emphasizing on the severe acute and late toxicities and the postoperative results of the analyzed studies. After identification, analysis and verification of eligibility criteria, eight studies were included in the meta-analysis. The methodological quality of the selected studies was assessed using the classic Oxford quality grading system (Jadad scale). The results obtained in this meta-analysis shows us that we can safely use both short-course radiotherapy and long-course radio-chemotherapy as neoadjuvant treatment for locally advanced rectal cancer, without significant differences regarding to severe acute or late toxicities, positive resection margins R+ or the number of local pelvic relapses at three years.