[Use of the AgNOR method for the differential diagnosis of tumors and for the quantification of non-neoplastic epidermal hyperproliferation in dermatohistology].

The AgNOR number (NN) and the AgNOR quotient (NQ) of 228 melanocytic, epidermal and fibrohistiocytic lesions were investigated by image analysis. In melanocytic nevi, dysplastic nevi and Spitz nevi, significantly less AgNORs were seen than in malignant melanomas and melanomas in situ. Significant differences in AgNOR expression were detected between the subtypes of melanoma, too. Epidermal carcinomas showed a significantly higher AgNOR expression than keratoacanthomas and other benign tumors. Between the G1 carcinomas and the G2 and G3 groups, an increase of the NN and NQ was found. Actinic keratosis demonstrated a significantly lower AgNOR expression than carcinomas and--like M. Bowen--higher NN and NQ than the benign lesions. The lowest AgNOR results of fibrohistiocytic lesions were registered in regressive palmar fibromatosis and in scars, the highest in malignant fibrous histiocytomas. Between dermato-fibrosarcoma protuberans, atypical fibroxanthoma and malignant fibrous histiocytomas, significant differences were found to exist. Furthermore we examined the suitability of the AgNOR technique for quantification of epidermal cell kinetics in non-neoplastic epidermal hyperproliferations. Especially in the grading of psoriasis this technique is helpful. First convincing results could be achieved for the use of the AgNOR method in the verification of antiproliferative effects of new substances in an experimental mouse tail test. This study demonstrated that the AgNOR technique in addition to the dermatohistological differential diagnosis of tumors is useful for the quantification of antiproliferative effects of different treatments in hyperproliferative epidermal dermatosis.