Chromogenic in Situ Hybridization for HER-2/neu in Borderline (2+) IHC Carcinoma Breast

Breast carcinoma is the most common malignant tumor and leading cause of cancer death in women, with more than 1,000,000 cases occurring worldwide annually (Rosai, 2004). According to the survey of epidemiology and end results (SEER) data, the world wide incidence of breast carcinoma is 123 women per 100,000 and its incidence in Asia is 89.5 per 100,000 (Horner et al., 2009). The breast carcinoma is a most prevalent cancer in Pakistan with approximate prevalence of 14.2% (Khan et al., 2004). Prognosis and management of breast carcinoma is influenced by classical variable such as tumour histologic type and grade, tumor size, proliferation index, lymph node status, lymphatic / blood vessel invasion, status of hormone receptors estrogen receptor (ER) and progesterone receptors (PR) of the tumour and more recently HER-2/neu status (Sinczak-Kuta et al., 2007). The human epidermal growth factor receptor 2, HER-2 also known as HER-2/neu or c-erbB-2 is an oncoprotein located on chromosome 17q21. It is overexpressed in 20% to 30% of invasive breast carcinomas and is associated with the risk of aggressive disease and poor