Lymphohistiocytoid variant of malignant mesothelioma of the pleura: a series of 22 cases.

Mesopath Group, ERI 3 Inserm, CHU Caen, Caen, France.
American Journal of Surgical Pathology (Impact Factor: 4.59). 06/2007; 31(5):711-6. DOI: 10.1097/PAS.0b013e31802baad7
Source: PubMed

ABSTRACT The lymphohistiocytoid variant of diffuse malignant mesothelioma is rare with very few cases described in the literature. It is characterized by mesothelial cells with a histiocytelike appearance and an associated dense lymphoid infiltrate. We studied clinicopathologic features and immunohistochemical patterns of a series of 22 cases. The histiocytelike cells had a mesothelial immunophenotype: AE1/AE3 (100%), calretinin (100%), CK5/6 (46%), and EMA (52%). The prominent lymphoid component showed a cytotoxic T-cell immunophenotype. Prognosis was similar to that of a large series of epithelioid diffuse malignant mesotheliomas. Formely, it was classified within the sarcomatoid type. We suggest that it should be reclassified as an epithelioid variant because of its similar behavioural characteristics. There was no evidence of Epstein-Barr virus-related infection.

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