Neutropenia and febrile neutropenia (FN), which are docetaxel-related adverse effects (AEs), can be fatal. The castration status may impact the frequency of hematologic adverse events, according to a recent in vivo investigation. For a study, researchers sought to determine how the castration status of patients with metastatic prostate cancer (mPCa) affected the frequency of docetaxel-related adverse events (AE).

Between January 2015 and December 2021, they conducted a retrospective analysis of the medical records of 265 men with metastatic prostate cancer (mPCa) who received docetaxel, including 92 men with metastatic hormone-sensitive prostate cancer (mHSPC) and 173 men with metastatic castration-resistant prostate cancer (mCRPC). The Common Terminology Criteria for Adverse Events (CTCAE) was used to assess AEs. Using a logistic regression model, they looked at the risk variables for hematologic and nonhematologic AEs and the differences in incidence between mHSPC and mCRPC.

Individuals with the mHSPC were more likely to get primary prophylaxis against neutropenia than patients with the mCRPC (7.5% vs. 33%, P<0.001). Patients with mCRPC had incidence rates of severe neutropenia (CTCAE≥Grade 3) and FN of 89% and 16%, respectively, compared to 81% and 18% for patients with mHSPC among those without main prophylaxis. The age beyond 75 years of age and failure to provide primary prophylaxis was found to be independent risk factors for severe neutropenia (odds ratio [OR]: 2.39, 95% CI: 1.10-5.18 and OR: 15.8, 95% CI: 7.23-34.6, respectively) according to a logit regression analysis. An independent risk factor for FN was an Eastern Cooperative Oncology Group Performance Status (ECOG-PS) more than or around 1 (OR: 2.26, 95% CI: 1.13-4.54). The risks of severe neutropenia and FN were unrelated to the castration status (mHSPC vs. mCRPC).

Regardless of the disease condition, docetaxel treatment for mPCa patients did not increase the incidence of severe neutropenia or FN. Patients with inadequate PS are more likely to develop FN, but failure to deliver primary prophylaxis and advanced patient age are independent risk factors of severe neutropenia. The results might be used to help clinical decision-makers choose the best candidates for docetaxel therapy.