Short‐course radiation with consolidation chemotherapy does not increase operative morbidity compared to long‐course chemoradiation: A retrospective study of the US rectal cancer consortium

• Published in: Journal of surgical oncology Vol. 129; no. 2; pp. 254 - 263
• Main Authors: Bauer, Philip S., Gamboa, Adriana C., Otegbeye, Ebunoluwa E., Chapman, William C., Rivard, Samantha, Regenbogen, Scott, Mohammed, Maryam, Holder‐Murray, Jennifer, Wiseman, Jason T., Ejaz, Aslam, Edwards‐Hollingsworth, Kamren, Hawkins, Alexander T., Hunt, Steven R., Balch, Glen, Silviera, Matthew L.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.02.2024
• Subjects: Chemoradiotherapy - adverse effects; Chemotherapy; Colorectal cancer; Consolidation Chemotherapy; Consortia; Humans; Morbidity; Neoadjuvant Therapy - adverse effects; Neoplasm Staging; Radiation; rectal cancer; Rectal Neoplasms - pathology; Rectal Neoplasms - therapy; Retrospective Studies; short‐course radiation; total neoadjuvant therapy; United States > US; total neoadjuvant therapy; short-course radiation; morbidity; rectal cancer
• ISSN: 0022-4790; 1096-9098
• DOI: 10.1002/jso.27468

Background and Objectives Neoadjuvant short‐course radiation and consolidation chemotherapy (SC TNT) remains less widely used for rectal cancer in the United States than long‐course chemoradiation (LCRT). SC TNT may improve compliance and downstaging; however, a longer radiation‐to‐surgery interval may worsen pelvic fibrosis and morbidity with total mesorectal excision (TME). A single, US‐center retrospective analysis has shown comparable risk of morbidity after neoadjuvant short‐course radiation with consolidation chemotherapy (SC TNT) and long‐course chemoradiation (LCRT). Validation by a multi‐institutional study is needed. Methods The US Rectal Cancer Consortium database (2010–2018) was retrospectively reviewed for patients with nonmetastatic, rectal adenocarcinoma treated with neoadjuvant LCRT or SC TNT before TME. The primary endpoint was severe postoperative morbidity. Cohorts were compared by univariate analysis. Multivariable logistic regression modeled the odds of severe complication. Results Of 788 included patients, 151 (19%) received SC TNT and 637 (81%) LCRT. The SC TNT group had fewer distal tumors (33.8% vs. 50.2%, p < 0.0001) and more clinical node‐positive disease (74.2% vs. 47.6%, p < 0.0001). The intraoperative complication rate was similar (SC TNT 5.3% vs. 4.4%, p = 0.65). There was no difference in overall postoperative morbidity (38.4% vs. 46.3%, p = 0.08). Severe morbidity was similar with low anterior resection (9.1% vs. 15.3%, p = 0.10) and abdominoperineal resection (24.4% vs. 29.7%, p = 0.49). SC TNT did not increase the odds of severe morbidity relative to LCRT on multivariable analysis (OR 0.64, 95% CI 0.37–1.10). Conclusions SC TNT does not increase morbidity after TME for rectal cancer relative to LCRT. Concern for surgical complications should not discourage the use of SC TNT when aiming to increase the likelihood of complete clinical response.