Imaging Characteristics of Triple Receptor Negative versus Triple Receptor Positive Breast Cancer

Background triple receptor negative breast cancer (TNC) is defined as cancer negative for estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2) and understanding the imaging characteristics of immunosubtypes of breast cancer may helpful in management of the disease. Objectives to describe and compare the distinct imaging findings of TNC with triple receptor positive breast cancer (TPC) characteristics using mammography and ultrasound. Patients and methods This is a retrospective observational analysis of the data extracted from the information system database belonging to the Iraqi National center for cancer Research-Baghdad University during a 4-year period starting from January 2011 until November 2014. Sonographic and mammographic findings had been acquire from breast imaging reports. Results From overall 620 patients were included in this study, only 192 patients had full tumor receptor analysis, there were 55 women diagnosed as triple positive breast cancer and only 22 patients with triple negative breast cancer.36.4 % of TNC was found in young women aged under 40 years and shows positive family history of breast cancer. All patients with TNBC were detected clinically and was palpable. Pathologic grade-II and stage-II were more often observed in TNC (68.1 % and 50 % respectively) and 91 % of TNC were ductal carcinoma.7.1 % of TNC were occult on mammography versus 10.4 % of TPC. Mass without calcification was commonest mammographic presentation in both groups of breast cancer (64.3 % and 62.5 % respectively). Breast cancer was visible in patients with TNC and 3.6 % of lesions were occult in TPC. Well circumscribed, oval or round hypoechoic mass was most commonly presentation of TNC on ultrasound whereas TPC was frequently found as poorly circumscribed, irregular hypoechoic mass. Conclusions being familiar with distinctive imaging features of TNC compared to TPC would assist in evaluation of particular immunosubtypes of breast cancer and because of TNC lesions were may mimic a benign breast lesions therefore, using mammography combined with ultrasound will minimize false-negative cancer particularly in TNC subgroup of breast cancer.