Neoadjuvant chemoradiation is associated with decreased lymph node ratio in borderline resectable pancreatic cancer: A propensity score matched analysis.

Background: Lymph node ratio (LNR) and margin status have prognostic significance in pancreatic cancer. Herein we examined the pathologic and clinical outcomes in patients with borderline resectable pancreatic cancer (BRPC) following neoadjuvant therapy (NAT) and pancreaticoduodenectomy.

Methods: Patients who underwent treatment between January 1, 2012 and June 30, 2017 were included. Sequential patients in the BRPC group were compared to a propensity score matched cohort of patients with radiographically resectable pancreatic cancer who underwent upfront surgical resection. The BRPC group was also compared to sequential patients with radiographically resectable pancreatic cancer who required vein resection (VR) during upfront surgery.

Results: There were 50 patients in the BRPC group, 50 patients in the matched control group, and 38 patients in the VR group. Negative margins (R0) were seen in 72%, 64%, and 34% of the BRPC, control, and VR groups, respectively (P = 0.521 for BRPC vs. control; P = 0.002 for BRPC vs. VR), with 24% of the BRPC group requiring a vascular resection. Nodal stage was N0 in 64%, 20%, and 18% of the BRPC, control, and VR groups, respectively (P < 0.001 for BRPC vs. control or VR). When nodal status was stratified into four groups (N0, or LNR ≤ 0.2, 0.2-0.4, ≥ 0.4), the BRPC group had a more favorable distribution (P < 0.001). The median overall survival were 28.8, 38.6, and 19.0 months for the BRPC, control, and VR groups, respectively (log-rank P = 0.096).

Conclusions: NAT in BRPC was associated with more R0 and N0 resections and lower LNR compared to patients undergoing upfront resection for resectable disease.