Diagnosis of diffuse malignant mesothelioma: experience of a US/Canadian Mesothelioma Panel.

The experience of the US/Canadian Mesothelioma Panel with its first 200 cases is reviewed. The light microscopic diagnosis, histochemical findings, immunohistochemical findings, and electron microscopic features of malignant mesotheliomas are reviewed in the context of differential diagnosis. Reasons for referral of case material to the panel and lessons from follow-up of difficult and controversial cases are reported. Recommendations to general pathologists are made regarding evaluation and review of possible mesotheliomas.