[Level of estrogen receptors in breast tumors: role of ethnic factors]. / Soderzhanie retseptorov éstrogenov v opukholiakh molochnoi zhelezy: rol' éthnicheskikh faktorov.

Estrogen receptor levels have been assayed in breast cancer patients. A significant increase in receptor-negative tumors was found in Kazakh menopausal women. The proportion of receptor-positive tumors correlated inversely with tumor progression, irrespective of ethnicity. A significant rise in the incidence of receptor-negative tumors was recorded in Kazakh females with breast cancer stage III.