Breast cancer immunophenotype dynamic change

Aim. Comparative analysis of primary breast cancer and breast cancer local relapse phenotypes. Methods. 5808 patients with confirmed diagnosis of breast cancer, including 108 (1,86%) with local relapses, underwent surgical treatment from 2000 since 2011. 26 tumors were prospectively examined by histological and immunohistochemical methods using monoclonal antibodies to estrogen and progesterone receptors and to Her2/neu oncogene protein. Results were compared with corresponding parameters of primary tumours. Results. Local relapses occurred in 1,2% of cases after total mastectomy, and in 5,1% - after incomplete mastectomy. Surgical approach to patients with local relapse of breast cancer depended on tumor size. Ectomy of the relapsing tumor at the post-operation scar site or at anterior chest wall was preformed in 60 (55,6%) cases, simple mastectomy after incomplete mastectomy - in 33 (30,5%) cases, repeated incomplete mastectomy with breast reconstruction - in 12 (11,1%) cases, and loco-regional relapsing tumor ectomy - in 3 (2,8%) cases. Immunohistochemical phenotypes of primary and relapsing tumors were different in 15 out of 26 studied cases. Switch from hormone-negative to hormone-positive tumor was registered in 46,7% of cases, from hormone-positive to hormone-negative tumor - in 40%, isolated change of Her2/neu oncogene protein expression - in 13,3%. Conclusion. The hypothesis of change of breast cancer phenotype after treatment has been confirmed; changes of immunohistochemical parameters after the local relapse should be taken into consideration for defining the treatment tactics.

breast cancer, chemotherapy, antineoplastic drugs, local relapse, immunophenotype, immunohistochemistry, metaplasia, malignancy, Her2/neu oncogene protein, estrogen receptors, progesterone receptors