121P Brain Metastasis and Her-2 Status in Metastatic Breast Cancer (Mbc) in Oman

Abstract

ABSTRACT Background Brain metastasis (BM) is increasingly encountered in up to 30% of MBC. Her-2 is over expressed in 30% of breast cancer (BC) patients, and BM is diagnosed in up to 40% of Her-2 positive BC. The risk factors are younger age, premenopause, invasive ductal carcinoma, tumor size > 2 cms, positive lymph nodes, high tumor grade, estrogen receptor negativity, p53 mutation, Her-2 positivity, and BRCA1 mutation. This study was carried out to analyze the Her-2 status of BC in our population, assess the frequency of BM, and its correlation to Her-2 status. Patients and methods Breast cancer data from 2006-2010 at National Oncology Center - Royal Hospital Muscat Sultanate of Oman was retrospectively retrieved from electronic patient record system. The cases of BC were analyzed with respect to Brain metastasis and their Her-2 status, their respective hormone receptor status, survival, and time to BM. Results A total of 542 cases of BC were evaluable during the period 2006-2010. BM was seen in 58, out of which 6 has an undetermined Her-2 status. One case presented as BM, to be diagnosed later as BC. Two cases developed further distant metastasis after BM. Isolated Her-2 positive BC and triple negative BC (TNBC) seems to have a similar spectrum in terms of BM, though patho-biology might not be the same. Her-2 positive tumor appears to have BM earlier. Some rare late BM was observed especially in Her-2 negative tumors. One case with Her-2 positive tumor survived 5 years after diagnosis of BM. There were 7 male BC with 2/7 Her2 positive, but none had a BM. Conclusions As the treatment modalities and survival improves, BM is anticipated to be encountered frequently. The correlation of Her-2 positive BC and BM concerns clinical outcome and needs validation. There are many open questions of interest including prophylactic Intra thecal Trastuzumab, concurrent Trastuzumab with radiation therapy, and concurrent Capecitabine or Temozolamide with Trastuzumab. The justification of frequent MRI surveillance is also debatable. Dual Her-2 inhibition by Lapitinib and Trastuzumab is another arena of further controlled clinical studies. There is a need to develop strategies of early diagnosis and prevention in BM, or to identify the molecular guided higher risk groups. Disclosure All authors have declared no conflicts of interest.