The use of trastuzumab in the treatment of hormone refractory prostate cancer; phase II trial.
OBJECTIVE
To investigate the efficacy and toxicity of the antibody to the HER-2/neu receptor (trastuzumab, Herceptin) in the treatment of advanced hormone-refractory prostate cancer (HRPC).


METHODS
Eighteen patients with HRPC were recruited for this phase II trial in which they received trastuzumab for 12 weeks or until disease progression or unacceptable toxicity was documented. HER-2 receptor overexpression was evaluated using immunohistochemistry (IHC) and dual-color fluorescence in-situ hybridization (FISH) assays.


RESULTS
Trastuzumab as a single agent demonstrated little efficacy in treating HRPC. Two patients demonstrated stable disease based on a decrease in PSA level to less than 50% of baseline. No patient demonstrated a regression of radiographic bony or soft tissue metastatic disease. The medication was well tolerated in 16 patients (89%), and 2 patients (11%) had to be hospitalized for cardiac complications.


CONCLUSIONS
Trastuzumab (Herceptin) as a single agent demonstrated poor efficacy in treating HRPC. Based on promising results in treating breast cancer with regimens using Herceptin and cytotoxic agents, a similar combination approach might demonstrate better efficacy in treating HRPC.
Ziada
Ali
A
UCHSC, 4200 E. 9th Ave. C-319, Denver, CO, USA. al.barqawi@uchsc.edu
Barqawi
Albaha
A
Glode
L Michael
LM
Varella-Garcia
Marileila
M
Crighton
Frances
F
Majeski
Susan
S
Rosenblum
Mark
M
Kane
Madeleine
M
Chen
Lin
L
Crawford
E David
ED
D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D002277:Carcinoma / Q000188:drug therapy* / Q000473:pathology; D018450:Disease Progression; D019008:Drug Resistance, Neoplasm; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis; D000068878:Trastuzumab; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D017430:Prostate-Specific Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab