Prognostic significance of immunohistochemical expression of the HER-2/neu oncoprotein in bone metastatic prostate cancer

Urology. 2006 Jul;68(1):110-5. doi: 10.1016/j.urology.2006.01.060. Epub 2006 Jun 27.

Abstract

Objectives: To investigate the usefulness of the overexpression of the human epidermal growth factor receptor (HER-2) oncoprotein in patients with bone metastatic prostate cancer as a marker for the time to recurrence and outcome after endocrine therapy.

Methods: We studied 50 patients who had been diagnosed with bone metastatic prostate cancer. HER-2 overexpression in the prostatic tissue by biopsy was evaluated by immunohistochemistry using the Hercep test. The results were scored into four levels by two pathologists; scores greater than 1+ were considered positive.

Results: The HER-2 staining score was 0, 1+, 2+, 3+, and indeterminate in 28, 4, 11, 6, and 1 case, respectively. HER-2 was overexpressed (greater than 1+) in 21 patients (42%). The cause-specific survival and nonrecurrence rates were significantly lower in the HER-2-positive group than in the negative group (P = 0.0084 and P = 0.0485, respectively). Furthermore, the cause-specific survival rate after recurrence was significantly greater in the HER-2-negative group than in the positive group (P = 0.0247).

Conclusions: We consider that HER-2 overexpression, as measured by immunohistochemistry, may be useful as a marker of an unfavorable prognosis by predicting the interval until relapse and outcome after endocrine therapy in patients with bone metastatic prostate cancer.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Bone Neoplasms / secondary*
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Prognosis
  • Prostate / metabolism*
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / mortality
  • Prostatic Neoplasms / pathology*
  • Receptor, ErbB-2 / metabolism*
  • Survival Rate

Substances

  • Receptor, ErbB-2