Survival in Locally Advanced Pancreatic Cancer After Neoadjuvant Therapy and Surgical Resection

Abstract

Objective: The aim of the study was to identify the survival of patients with locally advanced pancreatic cancer (LAPC) and assess the effect of surgical resection after neoadjuvant therapy on patient outcomes.

Background: An increasing number of LAPC patients who respond favorably to neoadjuvant therapy undergo surgical resection. The impact of surgery on patient survival is largely unknown.

Materials and methods: All LAPC patients who presented to the institutional pancreatic multidisciplinary clinic (PMDC) from January 2013 to September 2017 were included in the study. Demographics and clinical data on neoadjuvant treatment and surgical resection were documented. Primary tumor resection rates after neoadjuvant therapy and overall survival (OS) were the primary study endpoints.

Results: A total of 415 LAPC patients were included in the study. Stratification of neoadjuvant therapy in FOLFIRINOX-based, gemcitabine-based, and combination of the two, and subsequent outcome comparison did not demonstrate significant differences in OS of 331 non-resected LAPC patients (P = 0.134). Eighty-four patients underwent resection of the primary tumor (20%), after a median duration of 5 months of neoadjuvant therapy. FOLFIRINOX-based therapy and stereotactic body radiation therapy correlated with increased probability of resection (P = 0.006). Resected patients had better performance status, smaller median tumor size (P = 0.029), and lower median CA19-9 values (P < 0.001) at PMDC. Patients who underwent surgical resection had significant higher median OS compared with those who did not (35.3 vs 16.3 mo, P < 0.001). The difference remained significant when non-resected patients were matched for time of neoadjuvant therapy (19.9 mo, P < 0.001).

Conclusions: Surgical resection of LAPC after neoadjuvant therapy is feasible in a highly selected cohort of patients (20%) and is associated with significantly longer median overall survival.

FIGURE 1.

Patient study selection flowchart.

FIGURE 2.

(A) Comparison of overall survival between resected and non-resected LAPC patients. (B) Comparison of overall survival between resected LAPC patients, and non-resected who underwent ≥5 months of chemotherapy (: non-resected patients who died, or progressed within 5 mo, or received <5 mo of neoadjuvant chemotherapy). LAPC indicates locally advanced pancreatic cancer.

FIGURE 3.

Comparison of overall survival between different chemotherapy regimens in non-resected locally advanced pancreatic cancer patients. CHT indicates chemotherapy; FFX, FOLFIRINOX; Gem, gemcitabine.

FIGURE 4.

(A) Comparison of overall survival in patients with negative (N0) versus positive (N1) nodal disease in final pathology report. (B) Comparison of overall survival in patients with negative (R0) versus positive (R1) resection margin.