Abstract
To determine the oestrogen receptor/progesterone receptor (ER/PR) and human epidermal growth factor receptor 2 (HER2) status in Saudi Arabian patients presenting with breast cancer to Princess Noorah Oncology Center (PNOC) and to explore the correlation of these markers to each other, to tumour type and to grade.
Pathology material and records of symptomatic patients presenting to the centre during 2001-2009 were reviewed for patients' age, tumour size, type and grade and ER/PR and HER2 immunohistochemistry (IHC) status using the Dako HercepTest Kit as well as fluorescence in situ hybridization (FISH) for HER2 IHC 2+ score cases, as per the 2007 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guidelines. There were 852 cases, with a mean age of 49years and a mean tumour size of 3.0 cm with 75% node positivity. Of all cases, 772 (90.6%) were ductal carcinoma; 64% were ER/PR(+) and 23% were HER2(+); triple-negative cases accounted for 24%.
ER/PR and HER2 status did not differ from that reported previously, showing a direct correlation to tumour type and grade of ductal carcinoma. However, a difference exists in the relatively lower ER positivity in patients aged >50 years and the higher percentage of triple-negative cases. This study would serve as a baseline for other future national studies and for planning strategies to targeted therapy.