FREQUENCY AND HISTOGENESIS OF PELVINE RETROPERITONEAL LYMPH-NODE INCLUSIONS OF THE FEMALE GENITAL-TRACT - AN IMMUNOHISTOCHEMICAL STUDY OF 34 CASES

Heterotopic tissue in lymph nodes is rare. Benign glandular lymph node inclusions (BGI) occur in 11.4% on average. Their histogenesis is sti ll obscure. We studied 34 out of 1,039 cases of retroperitoneal lymph nodes with BGI (3.35%) of women who were treated by radical hysterecto my by Wertheim-Meigs of a cervical carcinoma. The nodes were reexamine d by light microscopy and in 19 cases the antibodies MAK 6 (cytokerati ne cocktail), HEA 125, Ber EP-4 (for differentiation between mesotheli um and glandular differentiation), vimentin and CEA were additionally used. All BGI showed a strong expression of MAK 6 and in 57.9% and 73. 7% to HEA 125 and Ber EP-4, respectively. Positive reaction against vi mentin occured in 47.3 %, but often only single cells were positive. N one but one metastasis of an endometrioid adenocarcinoma of the cervix uteri of BGI expressed CEA. The BGI showed a capsular, trabecular or interfollicular location in more than 80% and in 44.1% an admixture of several cells at the lining epithelium was noted. No features usually associated with endometriosis, such as periglandular stroma or eviden ce of recent or old hemorrhage were seen. The results suggest that the BGI represent an endosalpingiosis and is therefore of secondary Mulle rian origin. Some light microscopic features favoring the benign origi n (location in the nodes, lining cells of multiple types, lack of mito ses and cellular atypism, no desmoplastic stroma reaction, presence of periglandular basement membrane) may be helpful in distinguishing met astasis of serous ovarian borderline tumors. Negative reaction against CEA and the cellular morphology can preclude metastases of an endomet rioid adenocarcinoma of the cervix uteri as well as of a mucinous ovar ian bordeline tumor.