Rectal Sparing Approach After Neoadjuvant Therapy in Patients with Rectal Cancer: The Preliminary Results of the ReSARCh Trial.

BACKGROUND: Rectum-preservation for locally advanced rectal cancer has been proposed as an alternative to total mesorectal excision (TME) in patients with major (mCR) or complete clinical response (cCR) after neoadjuvant therapy. The purpose of this study was to report on the short-term outcomes of ReSARCh (Rectal Sparing Approach after preoperative Radio- and/or Chemotherapy) trial, which is a prospective, multicenter, observational trial that investigated the role of transanal local excision (LE) and watch-and-wait (WW) as integrated approaches after neoadjuvant therapy for rectal cancer. METHODS: Patients with mid-low rectal cancer who achieved mCR or cCR after neoadjuvant therapy and were fit for major surgery were enrolled. Clinical response was evaluated at 8 and 12 weeks after completion of chemoradiotherapy. Treatment approach, incidence, and reasons for subsequent TME were recorded. RESULTS: From 2016 to 2019, 160 patients were enrolled; mCR or cCR at 12 weeks was achieved in 64 and 96 of patients, respectively. Overall, 98 patients were managed with LE and 62 with WW. In the LE group, Clavien-Dindo 3+ complications occurred in three patients. The rate of cCR increased from 8- to 12-week restaging. Thirty-three (94.3%) of 35 patients with cCR had ypT0-1 tumor. At a median 24 months follow-up, a tumor regrowth was found in 15 (24.2%) patients undergoing WW. CONCLUSIONS: LE for patients achieving cCR or mCR is safe. A 12-week interval from chemoradiotherapy completion to LE is correlated with an increased cCR rate. The risk of ypT > is reduced when LE is performed after cCR.

Rectal Sparing Approach after preoperative Radio- and/or Chemo-therapy (ReSARCh): a prospective, multicenter, observational study.

BACKGROUND: Rectal-sparing approaches for patients with rectal cancer who achieved a complete or major response following neoadjuvant therapy constitute a paradigm of a potential shift in the management of patients with rectal cancer; however, their role remains controversial. The aim of this study was to investigate the feasibility of rectal-sparing approaches to preserve the rectum without impairing the outcomes. METHODS: This prospective, multicenter, observational study investigated the outcomes of patients with clinical stage II-III mid-low rectal adenocarcinoma treated with any neoadjuvant therapy, and either transanal local excision or watch-and-wait approach, based on tumor response (major or complete) and patient/surgeon choice. The primary endpoint of the study was rectum preservation at a minimum follow-up of 2 years. Secondary endpoints were overall, disease-free, local and distant recurrence-free, and stoma-free survival at 3 years. RESULTS: Of the 178 patients enrolled in 16 centers, 112 (62.9%) were managed with local excision and 66 (37.1%) with watch-and-wait. At a median (interquartile range) follow-up of 36.1 (30.6-45.6) months, the rectum was preserved in 144 (80.9%) patients. The 3-year rectum-sparing, overall survival, disease-free survival, local recurrence-free survival, and distant recurrence-free survival was 80.6% (95% CI 73.9-85.8), 97.6% (95% CI 93.6-99.1), 90.0% (95% CI 84.3-93.7), 94.7% (95% CI 90.1-97.2), and 94.6% (95% CI 89.9-97.2), respectively. The 3-year stoma-free survival was 95.0% (95% CI 89.5-97.6). The 3-year regrowth-free survival in the watch-and-wait group was 71.8% (95% CI 59.9-81.2). CONCLUSIONS: In rectal cancer patients with major or complete clinical response after neoadjuvant therapy, the rectum can be preserved in about 80% of cases, without compromising the outcomes.