14.02 Impact of Minimally Invasive Distal Pancreatectomy on Use of Chemotherapy for Cancer and Survival

K. L. Anderson1, M. A. Adam2, S. Thomas3, S. A. Roman2, J. A. Sosa2,4 1Duke University School Of Medicine,Durham, NC, USA 2Duke University Medical Center,Department Of Surgery,Durham, NC, USA 3Duke University,Department Of Biostatistics,Durham, NC, USA 4Duke Clinical Research Institute,Durham, NC, USA

Introduction: Interest in minimally invasive distal pancreatectomy (MIDP) has increased. Published data examining impact of MIDP on survival are limited to experiences from high-volume institutions. Our aims were to compare adjuvant chemotherapy use and overall survival between MIDP and open surgery (ODP).

Methods: Adult patients undergoing distal pancreatectomy for Stage I and II pancreatic adenocarcinoma were identified from the National Cancer Data Base, 2010-2012. Univariate and multivariate regression and survival analysis were employed to examine the association between MIDP (laparoscopic or robotic) vs. ODP and use of adjuvant chemotherapy and oncologic outcomes.

Results: A total of 1,807 patients underwent distal pancreatectomy for adenocarcinoma at 506 institutions: 505 (28%) MIDP, and 1,302 (72%) ODP. Use of MIDP from 2010 to 2012 increased from 131 (26%) to 209 (41%) cases. The majority of MIDP cases were performed at academic institutions (68%) compared to comprehensive community (30%) and community hospitals (2%). After adjustment, compared to patients who underwent ODP, those who underwent MIDP were more likely to have complete tumor resections [OR 1.53 (CI 1.09-2.17), p=0.02] and a shorter hospital length of stay (LOS) [-11%, (CI -5% to -16%), p=0.0002]. MIDP is associated on average with an 11% shorter LOS, which would be a reduction of about 1 day from the average ODP LOS of 10 days. The rates of 30-day readmission [OR 1.11 (0.72-1.72), p=0.62] and 30-day mortality [OR 0.83 (0.65-1.06), p=0.13] were similar between groups. Patients undergoing MIDP vs. ODP were more likely to receive adjuvant chemotherapy [OR 1.26 (1.00-1.60), p=0.05]; time to initiation of adjuvant chemotherapy was not different between groups [-2%, (CI -8% to 4%) p=0.45). Median follow-up was 17 months (IQR 10-26 months). In unadjusted analysis, 3-year survival was similar between MIDP and ODP (40% vs. 37%, p=0.42). After adjustment, overall survival for MIDP vs. ODP remained similar (HR 0.85, (CI 0.67-1.10) p=0.21).

Conclusion: Over the years, utilization of MIDP has increased, with the majority of procedures performed at academic institutions. It is associated with increased use of adjuvant chemotherapy; further study is needed to understand the etiology and impact of this association.