The role of cytology in the diagnosis of Paget's disease of the nipple.

Although rare, eczematous skin changes ascribed to Paget's disease of the nipple nevertheless warrant timely diagnosis. However this may occasionally be delayed due to a reluctance to proceed to traditional diagnostic techniques of wedge biopsy, surgical excision or punch biopsy. In this communication we describe 11 cases of unilateral mammary Paget's disease, in which an unequivocal cytodiagnosis was made from nipple scrapings. In five of these cases an underlying ductal carcinoma of the breast was simultaneously diagnosed by fine needle aspiration (FNA) cytology of a palpable breast lump. All 11 cases were subsequently proven histologically to be Paget's disease. Despite the fact that the use in dermatology of scrape smears and fine needle aspiration cytology remains somewhat unpopular, it is suggested that the screening of any eczematous skin change of the nipple should be considered using the simple, reliable and non-invasive technique of scrape cytology.