6th ESACP Congress, Heidelberg, April 7-11, 1999

A150
DNA IMAGE CYTOMETRY (ICM-DNA) IN HUMAN SWEAT GLAND TUMORS
Vogelbruch M *, Böcking A **, Kapp A *, Kiehl P ***

* Department of Dermatology and Allergology, Hannover Medical University, Germany ** Institute of Cytopathology, University of Düsseldorf, *** Dermatohistopathology and Electron Microscopy Unit, Hannover, Germany.

BACKGROUND The histopathological differentiation of well-differentiated carcinomas and benign atypic adenomas of sweat gland origin may be difficult, even if immunohistochemical methods are used in addition. We could demonstrate in a previous study, that DNA image cytometry (ICM-DNA) can be helpful in assessing the dignity of recurrent clear cell hidradenoma. In this study, a larger series of sweat gland tumors, clear-cut malignant or benign by histopathological criteria, was examined by ICM-DNA. MATERIALS AND METHODS 16 sweat gland carcinomas and 41 benign sweat gland tumors were examined. DNA image cytometry ( ICM-DNA ) was conducted according to the actual recommendations of the ESACP task force on standardization of ICM-DNA on enzymatic cell separation specimens of paraffin embedded material with the Autocyte Quic-DNA workstation using mesenchymal cells as internal reference. DNA-aneuploidy was detected by the stemline interpretation according to Böcking and/or 3 or more 5c-exceeding events. A classifier for sweat gland tumors could be constructed out of 37 DNA-euploid stemlines of the benign tumors by use of the EUROQUANT server, Dresden (Haroske et al. 1998). RESULTS DNA-aneuploidy was detected in 56,25% (9/16) of the sweat gland carcinomas, but in none of the 41 adenomas. CONCLUSIONS The detection of DNA-aneuploidy in sweat gland tumors using ICM-DNA seems to be a clear and specific indicator of prospective malignancy. However, regarding a sensitivity of about 56%, malignancy cannot be excluded if DNA-aneuploidy is not detected in a sweat gland tumor.