Perioperative outcomes for robotic total mesorectal excision after preoperative chemoradiation for rectal cancer.

732 Background: Laparoscopic total mesorectal excision (TME) after preoperative chemoradiation therapy (P-CRT) for mid to low rectal cancer was shown to be safe and feasible by a recent randomized trial (COREAN trial). However, the safety and short-term efficacy for robotic assisted laparoscopic TME has not been demonstrated. This study is a review of the perioperative outcomes of robotic TME after P-CRT for mid to low rectal cancer at our institution. Methods: All patients that underwent robotic TME after P-CRT for rectal cancer were retrospectively reviewed in our prospectively maintained, IRB-approved surgical oncology database. All relevant demographic, clinical, operative, pathology and perioperative data were analyzed. These were compared to the COREAN trial results. Results: From 2010 to 2014, 42 patients underwent robotic TME for rectal cancer after P-CRT. Mean patient age was 60+/-13. Robotic low anterior resections (R-LAR) were performed in 69% and 31% had a robotic abdominoperineal resection (R-APR). A majority were obese patients as 74% had a BMI ≥ 25, and 50% had an ASA ≥ 3. Conversion to open rate was 9.5% (n = 4) but 3 of these were within the first 8 cases. Median estimated blood loss was 105 ml (50-400 ml). The 30-day major complication rate (Clavien III-IV) was 11.9% (n = 5) and 90-day rate was 14.2% (n = 6). One patient (2.4%) had an anastomotic leak. There were no mortalities within 90-days from operation. Median length of stay was 7 days (6-12 days). Pathological complete response was 19% while 24% had no response. The average number of lymph nodes harvested was 14.2+/-9.5. The circumferential resection margin was negative in 95.2% (n = 40) of patients. Conclusions: As compared to laparoscopic TME patients in the COREAN trial, the robotic patients in our series were more obese and had a higher ASA classification. Our conversion rate was slightly higher, but this was related to the learning curve. All other short-term outcomes were similar. It appears that robotic TME is safe and feasible after P-CRT even among a more obese and higher risk population than previously reported in large series.