Chemotherapy-induced neutropenia as a prognostic factor in patients with unresectable pancreatic cancer.

Purpose: We conducted a retrospective cohort study to examine whether neutropenia could be an indicator of good prognosis in patients treated with gemcitabine (GEM) for unresectable pancreatic cancer.

Methods: A total of 178 patients with unresectable pancreatic cancer, who were treated with first-line (n = 121) or second-line (n = 57) GEM, were included in our analyses. A Cox proportional hazard model was used to examine the effect of the grade of GEM-induced neutropenia on prognosis. Furthermore, the difference in survival time for each grade was assessed using a log-rank test.

Results: In the first-line population, the hazard ratios of patients with grade 2 or grade 3 neutropenia compared with the ratios of those without neutropenia (grade 0) were 0.43 (95% CI 0.27-0.70) and 0.37 (0.21-0.65), respectively (p < 0.05). The median survival time (MST) was 3.8 months for grade 0, 9.4 months for grade 2, and 10.1 for grade 3. Landmark analysis of the second-line population revealed a hazard ratio of 0.52 (0.30-0.82) for grade 1 and 0.49 for grade 2 (0.28-0.72) (p < 0.05). MST was 1.3 months for grade 0, 4.7 months for grade 1, and 4.6 months for grade 2.

Conclusions: We found that neutropenia grade was an indicator of good prognosis in patients treated with first-line and second-line GEM for unresectable pancreatic cancer. A prospective study should be performed to examine whether dosage adjustment using neutropenia grade as an indicator would improve prognosis.