[OA-32] Analysis of tissue zinc levels in breast cancer subtypes

Vasin Chantaraponpun1, Thirayost Nimmanon2 and Chetana Ruangpratheep2

  1. Division of Anatomical Pathology, Army Institute of Pathology, Bangkok, Thailand
  2. Department of Pathology, Phramongkutklao College of Medicine, Bangkok, Thailand

Our previous study has been discovered that the zinc levels were significantly higher in the surrounding normal breast tissue compared to the invasive breast carcinoma (IBC) tissue. The objective of this study was to quantitatively analyse tissue zinc levels in molecolar subtypes of IBC. Zinc concentrations were evaluated in 45 formalin-fixed, paraffin-embedded tissue sections of IBC by the inductively coupled plasma optical emission spectrometry (ICP-OES) method. Molecolar subtypes of IBC were classified by immunohistochemical reactivities for oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and Ki67 proteins. At the 95% confidence interval, the correlation of tissue zinc levels with immunoexpressions and molecolar subtypes was assessed. Forty-five IBC cases were categorised into three main subtypes, i.e. luminal (14 cases), HER2-positive (10 cases) and triple-negative (17 cases) breast cancers. Four cases were not classified because they revealed an equivocal HER2 expression (score 2+). Tissue zinc levels had no significant relationship with hormone receptor (ER, PR and HER2) status, KI67 proliferation index and molecolar subtypes. In conclusion, intracellolar zinc may not alter significantly during the development of breast cancer molecolar subtypes.

Keywords: ICP-OES; immunoexpression; invasive breast carcinoma; molecolar subtypes; tissue zinc