Chemotherapy-related myelosuppression as a marker of survival in epithelial ovarian cancer patients.

OBJECTIVE: Authors have suggested that chemotherapy-induced neutropenia could represent a surrogate parameter of cancer stem cell response to treatment. Thus, the aim of this study was to evaluate the association of relative chemotherapy-induced neutropenia with survival in advanced epithelial ovarian cancer (EOC).
METHODS: A computerized database identified patients for primary advanced EOC with 6 cycles of platinum-taxane-based chemotherapy. Data collected included demographics, chemotherapy administration, laboratory evaluation, and survival outcomes. Relative neutropenia, defined as an absolute neutrophil count (ANC) <1000/mm3 at chemotherapy cycle nadir, was evaluated and correlated to PFS, OS, and platinum sensitivity (recurrence >6 months from completion of chemotherapy).
RESULTS: 255 patients were identified. Patients with neutropenia (n=203) during treatment were similar to patients who never had neutropenia (n=52) in regards to age, race, body mass index (BMI), stage, histology, grade, and debulking status. Neutropenic patients demonstrated improvements in PFS (14 vs. 6 months; p=0.01), OS (45 vs. 29 months; p=0.03) and platinum sensitivity rates (69% vs. 44%; p=0.001). As the number of neutropenic episodes increased, improvements in PFS (range 6 to 17 months; p=0.07) and platinum sensitivity (range 44% to 90%; p=0.002) was demonstrated. When stratified by debulking status, neutropenia conferred a survival advantage in suboptimally debulked patients, but only demonstrated marginal improvements in optimally debulked patients.
CONCLUSIONS: Our data demonstrates that patients with chemotherapy-induced neutropenia is associated with a survival advantage in ovarian cancer, especially in suboptimally debulked patients.