Purpose: Baseline neutrophil count may predict overall survival (OS) in patients with locally advanced pancreatic cancer (LAPC).
Methods and materials: The international multicenter randomized LAP07 phase 3 trial has enrolled 442 patients with LAPC. We analyzed the prognostic value of both baseline neutrophilia (neutrophil count >7 g/L) and elevated or increasing neutrophil count as (1) neutrophilia or (2) increased absolute neutrophil count after induction chemotherapy versus baseline for OS, progression-free survival, and local control (LC). A Cox proportional hazard model was used to assess elevated or increasing neutrophil count status by randomly assigned treatment interactions for each endpoint.
Results: Among the 442 patients, 47 patients (11%) with baseline neutrophilia had worse OS (median 8.9 vs 13.3 months; P = .01). After induction chemotherapy, among the 235 patients whose blood counts were available, 90 patients (38%) had elevated or increasing neutrophil count associated with poorer OS in univariate (median 14.4 vs 17.9 months; P = .001) and multivariate analysis (P = .004). Elevated or increasing neutrophil count was also predictive of a decreased benefit of chemoradiation therapy on LC. In 126 patients without elevated or increasing neutrophil count, 1-year LC was 80% in the chemoradiation arm versus 54% in the chemotherapy arm (P < .001; interaction test P = .015).
Conclusions: In this study, baseline neutrophilia and increased absolute neutrophil count were associated with worse OS in this large series of patients with LAPC. In addition, the counts were an independent prognosis factor and a strong predictive LC biomarker for chemoradiation therapy benefit. An assessment of neutrophils counts can help to improve the selection of patients who might benefit from chemoradiation therapy after induction chemotherapy.