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An external quality assessment scheme (EQAS) in the technical aspects of histopathology is described, and the results obtained over a two-year period assessed. The scheme involved 42 laboratories of varied work load, and the slides returned by the laboratories, both haematoxylin and eosin and special stains were marked by panels of four assessors. The reliability of assessment was checked by comparing the results of two separate panels of assessors, and by asking the same panel to assess the same set of slides on a different occasion. The participants' evaluation of the scheme was tested by questionnaire. The results show that the scheme described was considered to be of value by the great majority of the participants. The assessment of the slides by a panel was shown to be both reliable and reproducible. We believe that a general application of schemes such as the one described will maintain and improve standards in histopathology laboratories.

A 31-year-old woman presented with a cystic mass in the left breast. At fine needle aspiration (FNA), the mass felt gritty, and a firm mass remained after drainage of the cyst. Cytologic examination of the aspirate showed mononucleated malignant cells and an array of bizarre malignant multinucleated giant cells. A diagnosis of carcinoma of breast with malignant giant cells was made. Subsequent histologic study of the lesion showed a central cystic cavity lined by bizarre tumor giant cells. Immunocytochemistry and lectin cytochemistry confirmed the epithelial nature of the malignant giant cells. The entities that may yield giant cells on FNA of breast masses are discussed.

A pilot scheme for technical quality control in histopathology is described. The test material used and the methods of assessment and reporting are detailed. The scheme outlines not only interlaboratory comparison of technical performance but also provides a method of sharing uncommon material.

Particles of talc have been identified on the route surface of surgeons' rubber gloves and in sections of tissue classified as 'starch' or 'foreign body' granulomas. This analytical study indicates that under certain circumstances these granulomas could have been caused by talc contamination.

Three routine cervical smears were contaminated with adenocarcinoma cells from a malignant serous effusion which was being processed simultaneously in an automatic staining machine. Further investigation showed that cells were transferred in up to 17% of cases. However, with manual staining, the figure could be as high as 30%. The possibility of misleading cellular transfer should therefore always be considered. Serious fluids should not be processed with routine cervical smears.