[Histopathologic breast diagnosis in view of consultant studies of the Mamma-Regisstry Fulda]

The Mamma-Registry Fulda, founded in 1976 by the senior co-author, is a personal service for pathologists having problems with histological diagnosis of breast diseases. From nearly 7000 cases filed up to now we selected 1112 consecutive consultations from 1996 to 1999 for this study. The aims were a critical analysis of a "submission-profile" and for each case a comparison of submitters' diagnoses with that of the register to crystallize special fields of problems in histopathological diagnosis and to make a statement about quality standards which was shown in a raster of results. The submitted cases came from pathologists in university institutes (13.9%), city hospitals (49.0%), group practices (24.2%), and single practices (11.6%). The material consisted of selected paraffin-blocs in about two thirds and of slides only in less than one third. The sendings were accompanied by letters with sufficient information on history, clinical background, and gross findings in 72%, and in an additional rate of 17.1% by copies of the histological reports already given by the submitters to their clinicians. The main reasons for consultations were a primarily uncertain diagnosis (45.8%) or the request to affirm a more or less definite diagnosis (40.7%) in cases of rare lesions or differing judgements in the submitting institution. Each diagnosis of the registry was coded in a special diagnostic key. In a raster of results the diagnosis of each case was listed as identical (55.0%) when there was complete agreement between submitter's and register's result, as included (23.9%) when one of the differential diagnoses named by the submitter fitted the register's diagnosis, and as different (6.7%) when there was only agreement about the dignity of differently classified lesions. False positive (2.3%) and false negative (4.5%) diagnoses of submitters were subclassified as clinically irrelevant (2.6%) and relevant (4.2%). The most often missed diagnostic entity in the latter group was tubular carcinoma. Overall the results of the study justify awarding a high standard of quality to histopathological diagnostics.