Immunohistochemical detection of estrogen receptors on paraffin sections of normal, hyperplatic and carcinomatous endometrium.

The present study is the first dealing with the demonstration of estrogen receptors (ER) in up to 8-year-old paraffin blocks of endometrial curettage samples routinely fixed in 10% formalin. The Mab ER-ICA was used in a modified peroxidase-antiperoxidase method after pretreatment of paraffin sections with pronase. Eleven cases with proliferative, 11 cases with secretory endometrium, 20 cases with adenocystic, 21 with adenomatous hyperplasia and 27 endometrial adenocarcinomas were tested. The two main parameters, namely the percentage of ER-positive cells and the intensity of the immunostaining, were higher in the proliferative phase followed in a declining sequence by adenocystic hyperplasia, adenomatous hyperplasia, adenocarcinomas and the secretory phase of endometrium. Interestingly, the intensity of the immunostaining showed a positive relationship to the percentage of ER-positive cells (r = 0.93, p less than 0.001). It seems that the immunohistochemical demonstration of ER in paraffin sections of uterine specimens is an easy and reliable method for the mapping of the heterogeneous expression of ER and their comparative study with the well preserved histopathological features even in old archival paraffin-embedded material.

Interdigitating Reticulum Cell Sarcoma Positive immunohistochemistry for HLA-DR and two other activation antigens, CD30(Ki-1) and CD25(IL2R).

This communication reports a case of the rare interdigitating reticulum cell (IDRC) sarcoma of lymph nodes in a 46-year-old man. Extensive immunophenotypic analysis on paraffin and frozen sections revealed positivity on the neoplastic cells for protein S-100 as well as for antigens CD1, HLA-DR, CD4, CD25 (IL2R) and CD30 (Ki-1). The simultaneous positivity for the three activation antigens CD30, HLA-DR, and IL2R, a phenomenon mostly described in H and S-R cells of Hodgkin's disease, is discussed in particular.