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Preoperative Gemcitabine-based Chemoradiation Therapy for Borderline Resectable Pancreatic Cancer: Impact of Venous and Arterial Involvement Status on Surgical Outcome and Pattern of Recurrence

Objective: To evaluate the outcome of preoperative gemcitabine-based chemoradiation therapy (CRT) for borderline resectable pancreatic cancer (BRPC), focusing on the associations among the tumor-vascular relationship, surgical outcomes, and pattern of recurrence. Summary Background Data: Among the various multimodal treatment strategies for pancreatic cancer, preoperative CRT and subsequent surgery is 1 promising strategy for BRPC. Methods: A total of 184 patients with BRPC received preoperative CRT. BRPC was classified as follows, based on radiographic findings before the initiation of preoperative CRT: BR-V, a tumor involving the portal-superior mesenteric vein without arterial involvement; and BR-A, a tumor with the involvement of a relevant major artery. We assessed the association of these 2 subgroups with the following parameters: (1) resection rate, (2) survival, and (3) pattern of recurrence. Results: The resection rate of BR-V cases (84%) was significantly higher than that of BR-A cases (57%) (P < 0.001). The 5-year survival rates of the resected BR-V and BR-A cases were 51% and 25%, respectively (P = 0.003). The 5-year cumulative incidence of distant recurrence was significantly higher in the BR-A cases compared with the BR-V cases (67% vs 54%, P = 0.006); however, the 5-year cumulative incidence of local recurrence was not significantly different between the groups. Conclusions: In BRPC, arterial involvement was associated with impaired outcome regarding resection rate and survival, possibly due to the difference in the underlying pathophysiology between BR-V and the advanced nature of BR-A as a systemic disease.