Abstract
Purpose :
To analyze estrogen (ER), progesterone (PR), and human epidermal growth factor-2 (HER2) receptors expression in the primary tumor of patients affected by choroidal metastases of breast carcinoma (BC), and to compare these data with a control population composed by metastatic BC patients without choroidal involvement.
Methods :
Fifteen consecutive patients affected by choroidal metastases by BC were consecutively included. ER, PR and HER2 positivity (+) of the primary tumor were defined following standard guidelines (any positive nuclear staining (ie, > 1%) for ER and PR; an immunohistochemistry score of 3+ or immunohistochemistry score of 2+ plus fluorescent in situ hybridization with amplification ratio > 2.0 for HER2). Forty consecutive patient affected by metastatic BC without choroidal involvement were also included as a control group.
Results :
Patients affected by choroidal metastases by BC were characterized by ER+ in 15 cases (100%), PR+ in 13 cases (87%) and HER2+ in 3 cases (20%). Patient affected by metastatic BC without choroidal involvement were characterized by ER+ in 28 cases (70%), PR+ in 23 cases (58%) and HER2+ in 8 cases (19%). Patients affected by choroidal metastases by BC shows a statistically significant higher expression of ER (p=0.016) and PR (p=0.04) receptor in the primary tumor compared with non-choroidal metastatic BC. No difference for age, gender, race and histology of the primary tumor (ductal, lobular, others) were documented (P>0.05).
Conclusions :
There is growing evidence about differences in metastatic homing among BC biologic subtypes based on receptors status. Choroidal metastases by BC appeared associated with ER and PR receptors expression in the primary tumor. Although the proven longer survival of ER+ and PR+ patients may have a role in the development of choroidal metastases by BC, ER and PR receptors expression may influence the choroidal metastatic tropism of this tumor.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.