O184 MINIMALLY INVASIVE OESOPHAGECTOMY: A LONG LEARNING CURVE FOR BETTER ONCOLOGICAL RESECTION AND IMPROVED SURVIVAL OUTCOME
Authors: Di Maggio Francesco , Lee Ai Ru , Deere Harriet , Vrakopoulou Zoi , Botha Abrie 
Published: November 2019

Abstract

Aim
We wanted to investigate whether the established perioperative benefits of minimally invasive techniques, along with defined anatomical resection of the primary tumour (TARC), translate into long term survival benefit in a specialized high volume center.

Background & Methods
Minimally invasive oesophagectomy is technically demanding but benefits perioperative morbidity and intra-hospital mortality. We previously described open total adventitial resection of the cardia (TARC) as an optimal anatomical resection technique for lower oesophageal and gastro-esophageal junction cancers1. Long-term survival outcomes across our learning curve in adopting laparoscopic TARC are hereby assessed.
Data from 198 consecutive patients undergoing oesophagectomy by a single surgeon across two institutions was collected prospectively. Patient stratification was made to chronologically reflect four main stages of our learning curve: open surgery, Laparoscopic Ivor Lewis, laparoscopy/thoracoscopy with mini-thoracotomy and laparoscopic TARC. Primary outcomes included five-year survival rate, operating time, hospital stay, specimen lymphnodes. Peri-operative complications and mortality are also described.

Results
158 patients were male (79.8%); age was 63 +/- 10 years. 159 (78%) patients had neo-adjuvant chemotherapy. Overall five-year survival rate was 45%; peri-operative mortality rate was 1.5% (n=3). 13 patients were returned to theatre for surgical complications. Hospital stay was 22+/-23 days. Pathological specimen lymphnodes were 21+/- 8 (median: 20). Resection margins were negative (ACP) in 193 cases (97.4%); further than 1mm (RCPath) in 138 cases (69.7%).
The first 45 patients had open TARC surgery (26 Ivor Lewis, 17 trans-hiatal, one three-stage and one left thoracotomy). Laparoscopy (n=50) was initiated after two years, and thoracoscopic dissection (n=56) was introduced after case 94. Laparoscopic TARC was performed for the last 47 patients. Patients in the four groups had similar demographics, histological diagnosis, pre-operative and pathological staging, although the ones in the lap TARC group had a lower uptake of neo-adjuvant chemotherapy (64% versus 83%), mainly due to patient choice and co-morbidities.
Specimen lymph nodes for the four groups were: open = 20.5 +/-9.5; Lap = 19.5+/- 7; mini-tho = 19.9 +/- 7; lap TARC = 25 +/- 10 (p = 0.027). Resection margins were >1mm in 68.1% (open), 67.3% (lap), 64.2 (mini-tho) and 79.5% (lap TARC). Patients five-year survival rates during the 4 phases of the learning curve were 38.6%, 44.9%, 42.8% and 59% respectively, showing a benefit trend towards the end of the learning curve (p=0.03, log Rank Test).

Conclusion
Laparoscopic Anatomical resection of cancers of the OGJ requires a long learning curve. The evolution of performance and surgical technique through open and minimally invasive learning phases, along with the progress in oncological science, result in improved long-term survival.