Reduced-dose docetaxel for castration-resistant prostate cancer has no inferior impact on overall survival in Japanese patients.
BACKGROUND
In clinical practice, an adapted regimen with dose reduction is applied to castration-resistant prostate cancer (CRPC) treated with docetaxel because of its toxicity. However, there are few reports on the impact of dose reduction on survival.


METHODS
Fifty-seven patients with CRPC treated with first-line docetaxel in a single institution from 2005 to 2008 were evaluated retrospectively.


RESULTS
The median follow-up period was 20.5 months. Twenty-eight patients (49 %) received a standard 60 mg/m(2) regimen (SR), and 29 patients (51 %) received an adapted regimen (AR) with dose reduction. There was no difference in their baseline characteristics. The prostate-specific antigen response rates were not significantly different between the SR and AR groups (50 vs. 62 %, p = 0.36). Progression-free survival (PFS) and overall survival (OS) were also not significantly different between the groups (PFS 5.3 vs. 7.3 months, p = 0.39; OS 26.4 vs. 27.1 months, p = 0.53, respectively). No significant difference in the incidence of grade 3 or 4 adverse events was noted between the groups (89 vs. 83 %, p = 0.70). In multivariate analysis, hemoglobin and alkaline phosphatase were significant predictive factors for OS (hazard ratios 2.81 and 2.39, p = 0.012 and 0.024, respectively).


CONCLUSIONS
A reduced-dose regimen of docetaxel has no inferior impact on OS. Further studies on the optimal dose of docetaxel for Japanese patients are required.
Department of Urology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
Yuki
Y
Kita
Yosuke
Y
Shimizu
Takahiro
T
Inoue
Tomomi
T
Kamba
Koji
K
Yoshimura
Osamu
O
Ogawa
D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D044466:Asian People; D000077143:Docetaxel; D004305:Dose-Response Relationship, Drug; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D064129:Prostatic Neoplasms, Castration-Resistant / Q000188:drug therapy* / Q000401:mortality*; D012189:Retrospective Studies; D043823:Taxoids / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D043823:Taxoids; D000077143:Docetaxel; D017430:Prostate-Specific Antigen