gms | German Medical Science

Objective: Breast cancer (BC) is the most common cancer in women. Determination of receptor status (RS) in BC is very important for therapy, as well as prognosis. RS in metastasis can be different in comparison to primary tumor (receptor conversion). The aim of the present study was to analyze RS of breast cancer brain metastasis and find out a possible association between receptor conversion and clinical parameters.

Methods: The charts of all female patients operated for BC brain metastasis from July 2007 to June 2017 in a single center were reviewed. Inclusion criteria was determination of RS, comprising progesterone receptor (PR), estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) of primary BC and brain metastasis.Data was analyzed with special respect to age, location of brain metastasis, RS conversion, and two-years survival. Statistical analyses, comprising student’s t-test and Kaplan-Maier survival analysis were conducted using the SPSS version 22.0.

Results: 1109 patients (500 women, 609 men) with brain metastasis were operated during the study period, comprising 135 breast cancer brain metastasis patients. Inclusion criteria were fulfilled in 36 women. Median overall survival after brain metastasis diagnosis was 24,6 months (± 25,4). 27 (75 %) brain metastases revealed the identic, whilst 9 (25 %) revealed a receptor conversion of ER, 23 (64 %) the identic PR, with 13 (36 %) conversion of ER, and 34 (94 %) identic HER2, with 2 (6 %) conversion. Conversion of ER was predominantly found in supratentorial metastases (p = 0.036) and was associated with significant better 2 years survival (p = 0.05). All patients with gain of PR expression were alive at 2-years follow-up.

Conclusion: A receptor conversion of breast cancer brain metastasis is found in up to 40 % of patients. Conversion of ER is correlated with supratentorial location and improved survival. Gain of PR expression seems to be a positive prognosticator for 2-years survival.