Comprehensive immunohistochemical study of estrogen and progesterone receptor sensitivity and proliferative activity index (estrogen (ER) + progesterone (PR) Ki67)
The immunohistochemical study of estrogen receptors (ER), progesterone receptors (PR), and the proliferation marker Ki-67 is a key diagnostic test in oncomorphology that allows assessment of the hormonal sensitivity and biological aggressiveness of a tumor.
This study is most commonly used in breast tumors and plays a crucial role in selecting treatment strategy, including the need for hormonal therapy and disease prognosis.
What is assessed:
- Estrogen receptors (ER) - determine the tumor’s sensitivity to estrogens;
- Progesterone receptors (PR) - reflect the hormone dependence of the tumor and the functional activity of ER;
- Ki-67 - an indicator of proliferative activity that characterizes the tumor growth rate;
- comprehensive assessment of these markers allows classification of the tumor by molecular subtype and determination of prognosis.