Chemotherapy-induced neutropenia as a prognostic factor in patients with metastatic pancreatic cancer treated with gemcitabine.

PURPOSE: Chemotherapy-induced neutropenia (CIN) is a common side effect of chemotherapy and an important dose-limiting factor. However, an association between CIN development and longer survival was recently reported in several solid cancers. In the present study, we aimed to assess whether CIN could be a prognostic factor and clarify other prognostic factors for patients with metastatic pancreatic cancer. METHODS: We retrospectively analyzed the medical records of 84 patients who received gemcitabine monotherapy as first-line chemotherapy for metastatic pancreatic cancer to assess whether CIN could be a prognostic factor. Potential prognostic factors of survival were examined by univariate and multivariate analyses using the log-rank test and Cox proportional hazard model, respectively. RESULTS: Median survival time was 170 days [95% confidence interval (CI), 147-193] in patients without CIN (grade 0), 301 days (95% CI, 152-450) in patients with grade 1-2 CIN, and 406 days (95% CI, 271-541) in patients with grade 3 CIN. The multivariate analysis revealed that a pretreatment C-reactive protein level of <0.50 mg/dL [hazard ratio (HR), 0.534; 95% CI, 0.323-0.758, P = 0.015] and grade 3 CIN (HR, 0.447; 95% CI, 0.228-0.875, P = 0.019) were independent favorable prognostic factors in patients with metastatic pancreatic cancer treated with gemcitabine. CONCLUSIONS: Neutropenia during chemotherapy was associated with increased survival of patients with metastatic pancreatic cancer. Monitoring of CIN could be used to predict treatment responsiveness.

Drug-related genetic polymorphisms affecting severe chemotherapy-induced neutropenia in breast cancer patients: A hospital-based observational study.

Chemotherapy-induced neutropenia (CIN) is one of the major adverse events that necessitate chemotherapy dose reduction. This study aimed to evaluate the association between grade 4 neutropenia and genetic polymorphisms in breast cancer patients. In this genetic polymorphism association study, peripheral blood samples from 100 consecutive breast cancer outpatients, between August 2012 and September 2014, treated with doxorubicin and cyclophosphamide (AC) combination chemotherapy were genotyped for polymorphisms in adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1), cytochrome P450 (CYP) enzyme-coding genes (CYP2B6 and CYP3A5), glutathione S-transferase (GST), and excision repair cross-complementing 1 (ERCC1). Associations between grade 4 neutropenia and genotypes as well as risk factors were examined using multivariate logistic regression. From 100 patients, 32.0% had grade 4 neutropenia. Multivariate logistic regression analysis revealed that ERCC1 118C > T (odds ratio [OR], 3.43; 95% confidence interval [CI], 1.22-9.69; P = 0.020), CYP2B6*6 (OR, 4.51; 95% CI, 1.21-16.95; P = 0.025), body mass index (BMI) (OR, 6.94; 95% CI, 1.15-41.67; P = 0.035), and baseline white blood cell (WBC) count (OR, 2.99; 95% CI, 1.06-8.40; P = 0.038) were significant predictors of grade 4 neutropenia. ERCC1 and CYP2B6 gene polymorphisms were associated with the extent of grade 4 neutropenia in patients receiving AC chemotherapy. In addition to previously known risk factors, BMI and WBC counts, ERCC1 and CYP2B6 gene polymorphisms were also identified as independent strong predictors of grade 4 neutropenia.