Clinical Outcomes of Conversion Surgery after Neoadjuvant Chemotherapy in Patients with Borderline Resectable and Locally Advanced Unresectable Pancreatic Cancer: A Single-Center, Retrospective Analysis

The clinical benefit and potential risks of conversion surgery after neoadjuvant chemotherapy (NACT) have not been fully investigated in patients with borderline resectable pancreatic cancer (BRPC) and locally advanced unresectable pancreatic cancer (LAPC). Therefore, this has been evaluated in a retrospective, prospective cohort-based analysis. Between October 2005 and April 2017, 135 patients (65 with BRPC and 70 with LAPC) received conversion surgery after NACT. Exploratory analysis to assess clinical outcomes in comparison with patients who underwent upfront surgery in the same time period (n = 359) was also conducted. NACT with gemcitabine-based regimens (including gemcitabine monotherapy, gemcitabine-capecitabine combination, and gemcitabine-erlotinib combination) was used in 69 patients (51%) and FOLFIRINOX in 66 patients (49%). The median overall survival (OS) and disease-free survival (DFS) from the time of surgery was 25.4 months (95% CI, 18.6⁻32.2 months) and 9.0 months (95% CI, 6.8⁻11.2 months), respectively. The median OS and progression-free survival from the initiation of NACT was 29.7 months (95% CI, 22.5⁻36.8 months) and 13.4 months (95% CI, 12.5⁻14.4 months), respectively. In the exploratory analysis, conversion surgery after NACT was associated with a better median OS and DFS than upfront surgery (vs. 17.1 months; 95% CI, 15.5⁻18.7 months; p = 0.001 and vs. 7.1 months; 95% CI, 6.4⁻7.8 months; p = 0.005, respectively). There was no difference in length of hospital stay between the two groups, and conversion surgery after NACT showed a significantly lower incidence of postoperative complications than upfront surgery (38% vs. 27%, p = 0.03). Conversion surgery after NACT is a feasible and effective therapeutic strategy for the treatment of patients with BRPC and LAPC. Further clinical trials investigating optimal therapeutic strategies for BRPC and LAPC are warranted