Does castration status affect docetaxel-related adverse events? :Identification of risk factors for docetaxel-related adverse events in metastatic prostate cancer.

BACKGROUND

Docetaxel-related adverse events (AEs) such as neutropenia and febrile neutropenia (FN) can be life-threatening. A previous in vivo study raised the hypothesis that the castration status affects the rate of hematologic AEs. We aimed to investigate the impact of castration status on the incidence of docetaxel-related AE in metastatic prostate cancer (mPCa) patients.

METHODS

We retrospectively analyzed the records of 265 mPCa patients treated with docetaxel, comprising 92 patients with metastatic hormone-sensitive prostate cancer (mHSPC) and 173 patients with metastatic castration-resistant prostate cancer (mCRPC) between January 2015 and December 2021. Common terminology Criteria for Adverse Events (CTCAE) was applied to evaluate AEs. We analyzed the differential incidences between mHSPC and mCRPC, and risk factors of hematologic and nonhematologic AEs using a logistic regression model.

RESULTS

The rate of patients who received primary prophylaxis against neutropenia was higher in those with the mHSPC compared with those with the mCRPC (7.5% vs. 33%, p < 0.001). Among the patients without primary prophylaxis, incidence rates of severe neutropenia (CTCAE ≥ Grade3) and FN were 89% and 16% in patients with mCRPC compared to 81% and 18% in those with mHSPC. Logistic regression analysis revealed that age ≥ 75 years and failure to provide primary prophylaxis were independent risk factors of severe neutropenia (odds ratio [OR]: 2.39, 95% confidential interval [CI]: 1.10-5.18 and OR: 15.8, 95% CI: 7.23-34.6, respectively). Eastern Cooperative Oncology Group Performance Status (ECOG-PS) ≧ 1 was an independent risk factor of FN (OR: 2.26, 95% CI: 1.13-4.54). Castration status (mHSPC vs. mCRPC) was not associated with the risks of severe neutropenia and FN.

CONCLUSIONS

Castration status did not affect the risk of severe neutropenia or FN in mPCa patients treated with docetaxel regardless of the disease state. Failure to provide primary prophylaxis and advanced patient age are independent risk factors of severe neutropenia; while patients with poor PS are more likely to develop FN. These findings may help guide the clinical decision-making for proper candidate selection of docetaxel treatment.