Morphoimmunohistochemical characteristics of synchronous bilateral breast cancer

We performed a complex morphoimmunohistochemical study of synchronous bilateral breast cancer (diagnosed in 0.69% cases in women of the postproductive period after the age of 50). The molecular genetic characteristics of this cancer were detected and the algorithm of diagnostic studies was suggested. We have demonstrated that bilateral breast cancer was in 75% cases estrogen- and progesterone-positive, but androgen-negative. The HER-2/neu status of the tumor was negative in 75% cases, but expression of HER-2/neu was detected in the tumor of one mammary gland in 20% cases. Membrane expression of E-cadherin in infiltrative ductal cancer cells significantly decreased up to its complete disappearance with the decrease in tumor cell differentiation degree. The data provide new insight into prognostic value of the studied biomarkers and help to develop treatment protocol with consideration for the molecular biology of this group of tumors.