Status of HER2 amplification, polysomy17 and histopathological features of 425 Pakistani breast cancer patients

Tariq Moatter, Muniba Aban, Waseem Iqbal, Iqbal Azam, Afshan Pervaiz, Farjad Siddiqui, Farzana Murad, Shahid Pervez

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)

Abstract

HER2 gene amplification in invasive breast cancer is a robust predictive marker for response to transtuzumab therapy. This study was undertaken to measure concordance between immunohistochemistry (IHC) and FISH for HER2 gene amplification in invasive breast tumors, as well as the presence of polysomy 17 and possible correlation with demographics and histopathological variables, including ER and PR positivity. A total of 425 cases of infiltrating carcinoma of breast (99% IDC-NOS) were studied. HER2 over expression was tested by IHC and FISH methods. Association between IHC and FISH in both subsets was calculated by amplification ratio including polysomy 17. Out of 425 specimens, 128 (30%) were positive for HER2 amplification by FISH test, whereas only 78 (24%) tumors with 2+ expression showed amplification. In contrast, 39 (74%) demonstrated 3+ IHC score and HER2 gene amplification. The histological variables including tumor size, tumor type, and lymph node involvement did not influence the outcome of FISH analysis. The ER and PR status showed significantly greater positivity in patients negative for HER2 amplification. Polysomy 17 was detected in 23.7% patients and was positively associated with ER and PR expression (P= <0.05). Our study showed a concordance of 24% between 2+ IHC and FISH amplification, while in 3+ IHC cases the concordance was 74%. Significant links of HER2 amplification was seen with ER andPR negativity and higher tumor grade. In addition, non-significant correlations were noted with other variables like tumor type, size and lymph node status.

Original languageEnglish
Pages (from-to)3069-3073
Number of pages5
JournalAsian Pacific Journal of Cancer Prevention
Volume12
Issue number11
Publication statusPublished - 2011

Keywords

  • Breast cancer
  • FISH
  • Gene amplification
  • HER2
  • Immunohistochemistry
  • Pakistan
  • Polysomy 17

Fingerprint

Dive into the research topics of 'Status of HER2 amplification, polysomy17 and histopathological features of 425 Pakistani breast cancer patients'. Together they form a unique fingerprint.

Cite this