Efficacy and Safety of Docetaxel in Elderly Patients With Metastatic Castration-Resistant Prostate Cancer

Abstract

Purpose: Limited data are available about the tolerability and clinical outcomes of elderly patients with metastatic castration-resistant prostate cancer (mCRPC) who are treated with docetaxel. We evaluated the efficacy and safety of docetaxel as first-line chemotherapy for patients with mCRPC who were treated in our institution.

Materials and methods: We retrospectively identified patients with mCRPC and a Karnosfky performance status of 60% or greater treated with docetaxel on any schedule as first-line chemotherapy between 2008 and 2013. The primary end point was a comparison of median overall survival (OS) according to age in this population. Secondary end points were comparisons of the rates of severe toxicities, prostate-specific antigen (PSA) decline of 50% or greater, and time to progression (TTP). Results were stratified by three age groups: younger than 65 years, 65 to 74 years, and 75 years or older.

Results: Among the 197 patients included, 68 (34%) were younger than 65 years, 85 (43%) were 65 to 74 years, and 44 (22%) were 75 years or older. The mean number of comorbidities was not different among groups (1.19 v 1.32 v 1.43; P = .54). Patients younger than 65 years received a higher cumulative dose of docetaxel (450 mg/m2 v 382 mg/m2 v 300 mg/m2; P = .004). The rates of PSA decline of 50% or greater (41% v 47% v 36.4%; P = .51) and the median TTP (5.13 v 5.13 v 4.7 months; P = .15) were comparable among all groups. The median OS was longer in the group of patients younger than age 65 years (19.6 v 12.4 v 12.3 months; P = .012). Rates of any grade 3 or higher adverse event were not different among groups (63.2% v 71.8% v 54.5%; P = .14).

Conclusion: Administration of docetaxel in elderly patients who had good performance status was well tolerated. Rates of PSA decline and TTP were similar to those of younger patients, but median survival was lower.

Figures

Fig 1

Flow chart. A total of 280 patients were identified initially; 83 were excluded on the basis of exclusion criteria (inpatients when received chemotherapy [n = 7]; Eastern Cooperative Oncology Group performance status > 2 [n = 24]; received a previous chemotherapy regimen [n = 17]; received docetaxel as part of a study protocol [n = 10]; another concomitant primary tumor [n = 3]; received docetaxel combined with carboplatin [n = 2]; did not receive any chemotherapy [n = 4]; received the treatment at another institution [n = 1]; or did not have enough information on charts [n = 12]). KPS, Karnofsky performance status.

Fig 2

Time-to-treatment progression according to age group. HR, hazard ratio.

Fig 3

Kaplan-Meier curves for overall survival according to age groups. HR, hazard ratio.

Fig A1

Kaplan-Meier curve for overall survival of the whole cohort (15.6 months).