Prognostic impact of phosphorylated HER-2 in HER-2 + primary breast cancer

Naoki Hayashi, Takayuki Iwamoto, Ana M. Gonzalez-Angulo, Jaime Ferrer-Lozano, Ana Lluch, Naoki Niikura, Chandra Bartholomeusz, Seigo Nakamura, Gabriel N. Hortobagyi, Naoto T. Ueno

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Purpose. Tyrosine 1248 is one of the autophosphory-lation sites of human epidermal growth factor receptor (HER)-2. We determined the prognostic value of the expression level of tyrosine 1248-phosphorylated HER-2 (pHER-2) in patients with HER-2 + primary breast cancer using a reverse-phase protein array. Patients and Methods. The optimal cutoff value of pHER-2 for segregating disease-free survival (DFS) was determined by receiver operating characteristic (ROC) curve analysis. Five-year DFS for pHER-2 expression level was estimated with the Kaplan-Meier method using both derivation (n = 162) and validation (n = 227) cohorts. Results. Of the 162 patients in the derivation cohort, 26 had high HER-2 expression levels. The area under the ROC curve for pHER-2 level and DFS was 0.662. Nineteen of the 162 patients (11.7%) had high pHER-2 expression levels (pHER-2 high); 143 patients (88.3%) had low pHER-2 expression levels (pHER-2 low). Among the 26 patients with high HER-2 expression levels, the 17 pHER-2 high patients had a significantly lower 5-year DFS rate than the nine pHER-2 low patients (23.5% versus 77.8%). On multivariate analysis, only pHER-2 high independently predicted DFS in the Cox proportional hazards model. In the validation cohort, among 61 patients with high HER-2 expression, the difference in 5-year DFS rates between pHER-2 high (n = 7) and pHER-2 low (n = 54) patients was marginal (57.1% versus 81.5%).

Original languageEnglish
Pages (from-to)956-965
Number of pages10
JournalOncologist
Volume16
Issue number7
DOIs
Publication statusPublished - Jul 2011

    Fingerprint

Keywords

  • Breast cancer
  • HER-2
  • Metastases
  • Phosphorylation
  • Reverse-phase protein array

ASJC Scopus subject areas

  • Cancer Research
  • Oncology

Cite this

Hayashi, N., Iwamoto, T., Gonzalez-Angulo, A. M., Ferrer-Lozano, J., Lluch, A., Niikura, N., Bartholomeusz, C., Nakamura, S., Hortobagyi, G. N., & Ueno, N. T. (2011). Prognostic impact of phosphorylated HER-2 in HER-2 + primary breast cancer. Oncologist, 16(7), 956-965. https://doi.org/10.1634/theoncologist.2010-0409