Short-term outcomes of risk-adapted upfront docetaxel administration in patients with metastatic hormone-sensitive prostate cancer: a multicenter prospective study in Japan

We conducted a risk-adapted upfront docetaxel (DOC) in patients with metastatic hormone-sensitive prostate cancer (mHSPC). Here, we reported an interim analysis of the study. The study enrolled 68 patients with newly diagnosed mHSPC between 2016 and 2018. According to the presence of visceral metastasis, an EOD score ≥ 3, or prostate-specific antigen (PSA) level at 3 months of ≥ 1 ng/mL, patients were divided into low- and high-risk groups. Patients were treated with androgen deprivation therapy (ADT) with or without bicalutamide; those in the high-risk group received upfront treatment involving six cycles of DOC (70 mg/m²). Short-term treatment effect, adverse events, and quality of life (QOL) were evaluated. Fifty (73.5%) were classified in the high-risk group, and 46 (67%) received upfront ADT + DOC. In the ADT + DOC group, 43.5% (20/46) patients achieved a PSA level ≤ 0.2 ng/mL. PSA nadir and time to PSA nadir were 0.291 ng/mL and 288 days, respectively. In the ADT + DOC group, 76.1% (35/42) patients had adverse events (AEs) of grade ≥ 3. During a median follow-up of 18.5 months, 36.4% (8/22) patients in the ADT group and 43.5% (20/46) in the ADT + DOC group had CRPC. Two QOL scores including the physical status and appetite loss at 6 months significantly worsened in the ADT + DOC group but was resolved by 12 months. Upfront DOC achieved high PSA responses without long-term QOL deterioration. However, the short-term outcomes were limited. Longer follow-up is needed to determine the survival advantage.