title: Clinical outcomes by relative docetaxel dose and dose intensity as chemotherapy for Japanese patients with castration-resistant prostate cancer: a retrospective multi-institutional collaborative study.
abstract: BACKGROUND
  The aim of this study was to retrospectively investigate clinical outcomes by relative dose and dose intensity of docetaxel (DOC) as chemotherapy for Japanese patients with castration-resistant prostate cancer (CRPC).
  
  
  METHODS
  A total of 145 CRPC patients who received more than 4 courses of DOC chemotherapy at 14 hospitals between 2005 and 2011 were enrolled. Patients were divided into two groups--those receiving a higher or lower dose (mg/m(2)) or dose intensity (mg/m(2)/week). Differences between the groups regarding treatment outcomes and adverse events (AEs) were determined. Additionally, prognostic factors predictive of cancer-specific survival (CSS) in these patients were identified by both univariate and multivariate analysis.
  
  
  RESULTS
  The total patient group underwent a mean of 11.2 ± 7.4 DOC cycles, and the mean CSS after therapy was 15.6 ± 10.1 months. The higher-dose group had a better prostate-specific antigen (PSA) response than the lower-dose group. However, there was no significant difference between the groups in prognosis after DOC chemotherapy. Leukopenia and neutropenia were observed more frequently in the higher-dose group. Serum biomarkers (including PSA, lactate dehydrogenase and alkaline phosphatase), hemoglobin levels and presence of pain at initiation of chemotherapy, as well as the PSA nadir level on first-line hormone therapy, all were significant predictors of CSS.
  
  
  CONCLUSIONS
  In the Japanese population, relatively low-dose DOC chemotherapy had no deleterious effect on the CSS of CRPC patients, and a lower incidence of AEs occurred, in spite of a diminished PSA response compared with those receiving a higher dose.
authors.affiliation: Department of Urology, Toho University Sakura Medical Center, 564-1 Shimoshizu, Sakura, Chiba, 285-8741, Japan, naoto.kamiya@med.toho-u.ac.jp.
authors.forename: Naoto
authors.initials: N
authors.lastname: Kamiya
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Suzuki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ueda
authors.forename: Naohide
authors.initials: N
authors.lastname: Sato
authors.forename: Hiroomi
authors.initials: H
authors.lastname: Nakatsu
authors.forename: Kazuo
authors.initials: K
authors.lastname: Mikami
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sato
authors.forename: Kazushi
authors.initials: K
authors.lastname: Nomura
authors.forename: Koichiro
authors.initials: K
authors.lastname: Akakura
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Okano
authors.forename: Takemasa
authors.initials: T
authors.lastname: Ooki
authors.forename: Yukio
authors.initials: Y
authors.lastname: Naya
authors.forename: Sho
authors.initials: S
authors.lastname: Ota
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Masai
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Ichikawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000077143:Docetaxel; D004305:Dose-Response Relationship, Drug; D019008:Drug Resistance, Neoplasm; D064420:Drug-Related Side Effects and Adverse Reactions; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D064129:Prostatic Neoplasms, Castration-Resistant / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D012189:Retrospective Studies; D043823:Taxoids / Q000008:administration & dosage* / Q000009:adverse effects; D016896:Treatment Outcome
chemical_list: D043823:Taxoids; D000077143:Docetaxel; D017430:Prostate-Specific Antigen