Prolonged Castration Prior to Docetaxel Reduces Febrile Neutropenia in Patients With Metastatic Hormone-sensitive...

Triplet therapy, combining androgen deprivation therapy (ADT), darolutamide, and docetaxel has recently emerged as the standard first-line treatment for metastatic hormone-sensitive prostate cancer (mHSPC). Febrile neutropenia (FN) is a major clinical issue not only as a serious infection but also as a cause for early cessation or dose reduction of chemotherapy. However, little is known regarding the predictive factors for the development of FN in patients with mHSPC receiving triplet therapy.

This study enrolled 60 patients diagnosed with mHSPC across multiple institutions from 2023 to 2025. We examined clinical characteristics, treatment schedules, adverse events, and oncological outcomes. We focused particularly on the development of FN and used logistic regression analysis to investigate the predictive factors.

The median age was 72 years old, and 43 patients (73.3%) had high-volume disease at diagnosis. Nine patients (15%) developed FN. Multivariate logistic regression analysis identified older age [≥75, p=0.0161; hazard ratio (HR)=7.49], high-volume disease (p=0.0335), and shorter interval from ADT to docetaxel (<40 days) (p=0.0389; HR=7.86) as independent predictive factors of the development of FN. Notably, prolonged castration period prior to docetaxel (≥40 days) significantly reduced the risk of FN from 23.5% to 3.8% (p=0.0001). Patients who developed FN tended to have shorter castration-resistant prostate cancer progression-free survival (CRPC-PFS) compared to those who did not (p=0.0812; HR=3.2).

Older age and high-volume disease were independent risk factors for FN in patients with mHSPC receiving triplet therapy. A longer interval from ADT initiation to docetaxel (≥40 days) was associated with a significantly lower risk of FN, suggesting that extending the pre-docetaxel castration period is a practical, adjustable scheduling strategy to improve treatment safety. These findings may support treatment selection and proactive prevention of FN.