201P - Prognostic value of Ki-67 labeling index in patients with ductal intraepithelial neoplasia of the breast. Postsurgical outcome for 1171 women cared...

Date 30 September 2012
Event ESMO Congress 2012
Session Poster presentation II
Topics Breast Cancer, Early Stage
Biomarkers
Presenter Matteo Lazzeroni
Authors M. Lazzeroni1, E. Botteri2, A. Guerrieri Gonzaga1, M.C. Leonardi3, D. Serrano1, A. De Censi4, N. Rotmensz2, C. Varricchio1, B. Bonanni1, G. Puneri5
  • 1Division Of Cancer Prevention And Genetics, European Institute of Oncology, 20141 - Milan/IT
  • 2Division Of Epidemiology And Biostatistics, European Institute of Oncology, Milan/IT
  • 3Division Of Radiotherapy, European Institute of Oncology, Milan/IT
  • 4Medical Oncology, E.O. Ospedali Galliera, Genoa/IT
  • 5Division Of Pathology, European Institute of Oncology, Milan/IT

Abstract

The aim of this analysis was to investigate the prognostic relevance of Ki-67 labeling index (LI) in patients with Ductal Intraepithelial Neoplasia (DIN) of the breast. From January 1997 to December 2007, histopathologic and clinical data on 1,171 consecutive patients operated for DIN in a single institution were collected through the institutional clinical database. The study was performed in accordance with REMARK criteria. The independent prognostic role of Ki-67 LI was evaluated with a multivariable Cox regression model. Median age was 52 years, median Ki-67 LI 15% (range 1-80) and median follow-up was 86 months (range 1-192). A total of 872 (74.5%) patients underwent breast conservative surgery. Whole breast radiotherapy was administered to 356 patients, and 506 patients received endocrine treatment. Overall, 549 (46.9%) women were premenopausal at the time of diagnosis. In regard to histology, most DINs were solid or cribriform (75%), moderately-low differentiated (80%), with a low proliferating index (Ki-67 LI < 14%, 46%), and with estrogen receptor positive immunostaining (80%). Overall, ipsilateral recurrence of both invasive and in situ disease (5-year cumulative incidence) was 163 (10.7%). When dividing patients into three subgroups on the basis of Ki-67 LI (< 14%, 14-20% and >20%), the 5-year cumulative incidence of breast recurrences were 9.4%, 10.3%, and 13.0% respectively [Hazard Ratio (HR)14-20 vs <14: 1.52 (95% CI 1.00 - 2.32) and HR >20 vs <14: 1.99 (95% CI 1.24 - 3.19)]. HRs were adjusted for menopause, surgical margins, grade, estrogen receptor, progesterone receptor, c-erb B2, presence of necrosis, microcalcifications, radiotherapy, and endocrine therapy. Our data suggest that Ki-67 LI may be a useful marker of the clinical behavior of each DIN subgroups and consequently guide treatment choices.

Disclosure

All authors have declared no conflicts of interest.