Autori: A. Vieillefond, P. Beuzeboc, L. Mignot, E. Banu, F. Priou, E. Malaurie, P. Dalivoust, X. Muracciole, M. Sibony and S. Oudard

Editorial: Abstract 4700. J Clin Oncol (supplement) 2005;23(16S):427s., 2005.

Rezumat:

Background: The monoclonal antibody trastuzumab (Herceptin; H) is currently approved for therapeutic use in HER2 positive metastatic breast cancer. Data indicate that HER2 overexpression may be as high as 20–35% in UC, suggesting that H could be a feasible treatment option in this setting. Here, we describe the identification of patients (pts) eligible for a phase II randomized study of chemotherapy ± H in advanced or metastatic HER2 positive UC. Methods: Paraffin-embedded of tumors ± metastasis specimens from 76 pts with advanced or metastatic UC were studied immunohistochemically (IHC) with the Dako polyclonal antibody 1/1500. Correlation of HER2 expression with continous variables was tested by a Pearson’s test. Significance level was set at P<0.05, two-sided. To be included in our ongoing study, pts must either be IHC 3+ or IHC 2++ and FISH+, tested in a central laboratory. Pts will be randomized to receive gemcitabine (1000 mg/m2 day 1 and 8) and platinum salt (cisplatin 70 mg/m2 or carboplatin AUC 5, day 1, according to renal function), q3w ± H (8 mg/kg loading dose followed by 6 mg/kg q3w until disease progression). The primary endpoint is progression-free survival. Results: To date, 76 pts have been screened for HER2 status, between 02/2003 to 12/2004. Pts characteristics: median age 67 year (37–87 year), sex (F/M): 12/64. Thirty pts (39%) were eligible: 29 were IHC 3+ and one sample was IHC 2+ and FISH+. The others 46 pts were: IHC 2+ and FISH- (4 pts), IHC 1+ (6 pts) and HER2 negative (36 pts). Median HER2 quantitative expression of HER2 IHC 3+ was 100% (range 10–100%). No relationship with HER2 expression was registered for sex and age. Tumor and metastasis specimens (lymph nodes, liver) were tested for 3 pts and display the same expression. Among 30 positive pts, only 5 have currently been enrolled into the study. Conclusions: Our data demonstrate that UC is associated with a high rate (39%) of HER2 positivity, which provides the rationale for treatment with Herceptin in this disease setting. Results from this ongoing clinical trial will allow to determine HER2 eligible pts and assess the benefits of adding Herceptin to standard chemotherapy.

Cuvinte cheie: cancer de vezica urinara, expresieHER2 neu // bladder cancer, HER2 neu expression

URL: http://meeting.jco.org/cgi/content/abstract/23/16_suppl/4700