title: Prostate-specific antigen kinetics as a measure of the biologic effect of granulocyte-macrophage colony-stimulating factor in patients with serologic progression of prostate cancer.
abstract: OBJECTIVE
  To determine the biologic effect of granulocyte-macrophage colony-stimulating factor (sangramostim, GM-CSF; Immunex Corporation, Seattle, WA) as measured by prostate-specific antigen (PSA) kinetics in patients with serologic progression of prostate cancer after definitive local therapy.
  
  
  METHODS
  Patients with prostate cancer who had undergone previous definitive surgical or radiation therapy with nonmetastatic, recurrent disease as manifested by a rising PSA between 0.4 ng/mL and 6.0 ng/mL were enrolled on this phase II trial. Patients received 250 micro g/m(2)/day of subcutaneous GM-CSF on days 1 through 14 of a 28-day cycle. PSA was measured at day 1 of each cycle.
  
  
  RESULTS
  Thirty patients with serologic progression of prostate cancer were treated. The median pretreatment PSA was 2.9 ng/mL. Of the 29 evaluable patients, three patients (10%; 95% confidence interval, 2% to 27%) achieved a 50% reduction in PSA. For the patients (n = 26) in whom the on-treatment PSA doubling time could be calculated, the median PSA doubling time increased from 8.4 months to 15 months (P =.001), and the median slope of the PSA versus time curve decreased with treatment (P =.004). Therapy was well tolerated by all patients, with an average treatment duration of 16.5 cycles (range, 5 to 33).
  
  
  CONCLUSIONS
  GM-CSF has a biologic effect in patients with serologic progression of prostate cancer after definitive local therapy, as measured by PSA declines and modulation of PSA kinetics.
authors.affiliation: University of California San Francisco Comprehensive Cancer Center, San Francisco, CA 94115, USA. brini@medicine.ucsf.edu
authors.forename: Brian I
authors.initials: BI
authors.lastname: Rini
authors.forename: Vivian
authors.initials: V
authors.lastname: Weinberg
authors.forename: Robert
authors.initials: R
authors.lastname: Bok
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Small
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000188:drug therapy*; D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D017430:Prostate-Specific Antigen / Q000097:blood / Q000187:drug effects*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000188:drug therapy*; D018709:Statistics, Nonparametric
chemical_list: D000970:Antineoplastic Agents; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D017430:Prostate-Specific Antigen