Evolution in multimodality management of locally advanced rectal cancer.

Abstract

684 Background: This study reports the evolving multimodality management of locally advanced rectal cancer (LARC) and associated outcomes at a high volume center. Methods: Patients with Stage II/III LARC <15cm from the anal verge evaluated by the colorectal surgery service were identified from a prospective database. Clinical management including neoadjuvant therapy (NT) and surgical treatment along with pathologic and perioperative outcomes were collected. Results: Between June 2009 and March 2015, 798 patients were evaluated and received NT for LARC. Majority were staged cT3/T4 (84%) or cN+ (78%), and 635 had surgery within 26wks following NT. Reliance on MRI staging increased from 57% to 98% during the study period (P < 0.001). There was increased usage of total NT (NEO) with pre-op chemotherapy (CT) and chemoradiotherapy (CRT) (17% to 76%, p < 0.001) with a concomitant decrease in use of CRT alone (77% to 16%, p < 0.001) and post-op CT (70% to 15%, p < 0.001). The proportion undergoing surgery beyond 8wks after NT rose from 41% to 62% (P < 0.001) and beyond 8 wks after CRT rose from 45% to 72% (p < 0.001). The percentage of patients not undergoing resection by 26wks (nonoperative management) rose from 12% to 27%, P < 0.001). Minimally invasive surgery (MIS) increased from 33% to 71% (P < 0.001); in 2014-15 98% of MIS was robot-assisted. Over the study period there was a decrease in LOS (mean 8.1 to 6.5 days, p < 0.001), grade III-V complications (13% to 7%, p < 0.05), surgical site infections (25% to 8%, p < 0.001), and anastomotic leak (11% to 3%, p < 0.05). The proportion undergoing ileostomy closure within 15 wks rose from 7% to 73% (P < 0.001). Involved CRM rates decreased from 9% to 3% (P < 0.01). TNM downstaging increased from 62% to 74% (p = 0.002). Complete response rates (clinical and pathologic) at 26wks was 26% in 2009-10 and 32% in 2014/5 (p = 0.067). Conclusions: Over the past decade, there has been a shift to MRI staging, total NT (NEO), and MIS rectal resection at 8-12 weeks. This has been associated with higher response rates, shorter LOS, and fewer complications.