Affiliations of authors: S. Koscielny (Department of Biostatistics and Epidemiology), P. Terrier (Department of Pathology), M. Spielmann (Department of Medicine), J. C. Delarue (Department of Clincial Biochemistry), Institut Gustave-Roussy, Villejuif, France.
Correspondence to: Serge Koscielny, Ph.D., Institut Gustave Roussy, Department of Biostatistics and Epidemiology, 39 rue Camille Desmoulins, 94805 Villejuif, France (e-mail: koscieln{at}igr.fr).
Ferrero-Poüs et al. investigated the significance of low c-erbB2 protein values in a series of 488 patients to confirm or refute the results that we published last year (1,2) that suggested that low c-erbB2 protein expression is a negative prognostic factor for women with breast cancer. Their study did not demonstrate that low c-erbB2 protein expression is linked to a poor prognosis.
The results of the prognostic study that we published in the Journal (1) were preliminary and concerned 117 patients treated at the Institut Gustave-Roussy. These patients were part of a large multicenter study that included 1062 patients and showed that the proportion of estrogen receptor-negative tumors (49% = 54 of 110 tumors) was larger among patients with a low c-erbB2 value than in the rest of the population (21% = 197 of 947 tumors) and that this difference was statistically significant (two-sided P<10-9). Ferrero-Poüs et al. did not observe that association.
Since our earlier publication in the Journal, follow-up data have been obtained for 769 patients. The poor prognosis associated with low c-erbB2 values was confirmed (3) despite a low number of events (121 relapses or deaths, 3-year relapse-free survival = 86%) and a short follow-up (median, 38 months). The risk of relapse and death was greater for patients whose tumors had low c-erbB2 levels and those whose tumors exhibited high c-erbB2 levels than for those patients with intermediate expression. The relative risks (Cox's regression model, with intermediate expression as the reference category) of distant metastases and death were, respectively, 2.2 (95% confidence interval [CI] = 1.3-3.8; two-sided P = .005) and 2.3 (95% CI = 1.2-4.4; two-sided P = .01) for low expression. These results have not been published as yet in a full paper because we thought the follow-up period was too short.
This result has been confirmed by Pawlowski et al. (4) who showed that low concentrations of c-erbB2 messenger RNA (by real time reverse transcription-polymerase chain reaction analysis) are associated with a poor prognosis. Their study involved 404 unselected, primary human breast cancers.
To the best of our knowledge, four independent studies have evaluated the prognostic significance of low c-erbB2 expression. Three (3-5) of four have shown a poor prognosis associated with low c-erbB2 expression. This association merits further investigation.
REFERENCES
1
Koscielny S, Terrier P, Spielmann M, Delarue JC. Prognostic
importance of low c-erbB2 expression in breast tumors [letter]. J Natl Cancer
Inst 1998;90:712.
2 Koscielny S, Terrier P, Daver A, Wafflart J, Goussard J, Ricolleau G, et al. Quantitative determination of c-erbB-2 in human breast tumours: potential prognostic significance of low values. Eur J Cancer 1998;34: 476-81.[Medline]
3 Koscielny S, Terrier P, Daver A, Wafflart J, Goussard J, Ricolleau G, et al. Quantitative determination of c-erbB-2 in human breast tumors: potential prognostic significance of low values [abstract]. Breast Cancer Res Treat1998 ;50:308.
4 Pawlowski V, Revillion F, Hornez L, Peyrat JP. Low concentrations of c-erbB-2 mRNA (real time RT-PCR) are associated with a poor prognosis in 404 unselected primary breast cancers [abstract]. Proc Am Assoc Cancer Res 1999;40:1355.
5 Dittadi R, Brazzale A, Pappagallo G, Salbe C, Nascimben O, Rosabian A, et al. ErbB2 assay in breast cancer: possibly improved clinical information using a quantitative method. Anticancer Res 1997;17:1245-7.[Medline]
This article has been cited by other articles in HighWire Press-hosted journals:
![]() |
||||
|
Oxford University Press Privacy Policy and Legal Statement |