Risk factors for severe neutropenia among pancreatic cancer patients receiving nab-paclitaxel and gemcitabine combination therapy.

684 Background: Albumin-bound paclitaxel (nab-paclitaxel) and gemcitabine combination therapy (GnP therapy) significantly extends overall survival in patients with metastatic pancreatic cancer, compared to conventional gemcitabine monotherapy. However, severe neutropenia (Grade ≥ 3) occurred in 67.6% of patients in the Japanese phase I/II trials of GnP therapy, and is often a limiting factor. The purpose of this study was to identify the risk factors for severe neutropenia in pancreatic patients receiving GnP therapy in clinical settings. Methods: A retrospective study of 222 consecutive patients with pancreatic cancer who received GnP therapy at the Cancer Institute Hospital from December 2014 to December 2016 was conducted. Univariate and multivariate analyses were used to compare blood test values and patients’ characteristics between patients with no neutropenia or Grade 1/2 (non-serious) neutropenia and those with Grade ≥ 3 (severe) neutropenia. Results: There were 19 patients (8.6%) with modified FOLFIRINOX in the previous treatment history. The median doses of nab-paclitaxel and gemcitabine were 192.5 mg (range 134-277.5) and 1,545 mg (range 1,000-2,220), respectively. Severe neutropenia and febrile neutropenia occurred in 118 patients (53.2%) and 15 patients (6.8%), respectively. Multivariate logistic regression analysis indicated that ANC (absolute neutrophil count) < 3.03 x 10 3 /μL (OR: 4.806, 95% CI: 2.416-9.558, p = 0.000), T-Bil ≥ 0.6 mg/dl (OR: 1.964, 95% CI: 1.040-3.708, p = 0.037) and CRP < 0.13 mg/dl (OR: 2.607, 95% CI: 1.331-5.106, p = 0.005) were significant risk factors for severe neutropenia. The incidence rate of severe neutropenia was 85.7% (18/21) in patients with all three identified factors, while it was 27.7% (13/47) in patients with none of them. Age was not a risk factor in either univariate or multivariate analysis. Conclusions: Low ANC, high T-Bil, and low CRP were found to be risk factors for severe neutropenia in patients receiving GnP therapy. It would be desirable to monitor patients with these risk factors carefully, even if their values are within the standard ranges.