Brain metastases (BM) in patients presenting with HER-2 amplified advanced breast cancer (ABC).

Abstract #1060 Background : The HER-2 amplified breast cancer phenotype is suggested to have an increased propensity for CNS metastasis. The introduction of trastuzumab might be related to this association. In order to elucidate this relationship we analyzed our prospectively collected database of all patients presenting with metastatic HER-2 amplified breast cancer in the time frame between Jan 2002 until Dec 2004. Material and Methods : The AZ-Augustinus Breast Cancer Tissue Bank was initiated in 1999. It ensures the prospective entry of all clinical and pathological features of patients presenting in our Breast Clinic clinical database. The data entry is performed by dedicated Datamanagers and is linked to the Biological Repository Collection (tissue, serum, plasma, bone marrow). Patients presenting with primary metastatic, HER-2 amplified ( FISH +) between 2002 and 2004 were analyzed for this study. Since Jan 2002, all patients presenting with metastatic disease underwent a routine CT-scan of the brain as initial staging procedure. Results : A total of 33 patients presented with HER-2 +, unpretreated metastatic breast cancer. Mean age: 53 years (range 30-69). Sites of metastases at diagnosis ( % of patients) : liver: 71 %, lung: 36 %, bone: 86 %, brain (BM): 15 % (5), lymph nodes and others: 20%. In total 5/33 (15%) presented with brain only metastasis. During the follow-up period 17 more patients developed BM, amounting to 22/33 (67%). The median time between diagnosis of BM after diagnosis of ABC was 22 months (0 – 98). Mean time to developing BM was 18 months. In total 62 lesions in the CNS were counted on MRI in these 22 patients. 23 lesions (38%) had a cerebellar localisation. Conclusions: Assuming that the presentation with metastasis is a reflection of the unperturbed biology of disease, our data suggest that the CNS is not an exceptionally preferred site for metastasis in untreated HER-2 + advanced breast cancer. A preference for a cerebellar localisation is suggested. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1060.