Lymphohistiocytoid mesothelioma of the pleura

Pathol Int. 2010 Aug;60(8):566-74. doi: 10.1111/j.1440-1827.2010.02560.x.


Lymphohistiocytoid mesothelioma (LHM), reported to be a rare variant of sarcomatoid mesothelioma, is challenging to differentiate from non-Hodgkin's lymphoma due to marked lymphocytic infiltration. To aid accurate recognition of LHM, we examined immunohistochemical, in situ hybridization (ISH) of Epstein-Barr virus RNA (EBER-1) mRNA, fluorescence ISH (FISH) for homozygous deletion of 9p21, and asbestos analysis in four cases (three men and 1 woman). Three patients died, while Case 4 was still alive 19 months after extrapleural pneumonectomy. Histologically, these cases were characterized by heavy lymphocytic infiltration. All neoplastic cells were positive for calretinin, AE1/AE3, and epithelial membrane antigen, but negative for CEA. EBER1 factor was negative. FISH analysis demonstrated homozygous deletion of the 9p21 locus in three of the four cases. In Case 1: (i) autopsy findings showed mesothelioma primarily located in the right parietal pleura, but metastasized into the left lung and abdominal organs; (ii) the histological findings at autopsy indicated sarcomatoid mesothelioma; and (iii) we found asbestos bodies and fibers in extracts from lung tissue (Cases 1 & 4) using digestion with bleaching fluid. LHM, an infrequent variant of sarcomatoid mesothelioma, displayed homozygous deletion of the 9p21 locus (three of four cases), and has a relatively favorable prognosis for the sarcomatoid type.

MeSH terms

  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism
  • Female
  • Herpesvirus 4, Human / genetics
  • Herpesvirus 4, Human / metabolism
  • Humans
  • Immunohistochemistry
  • In Situ Hybridization
  • Male
  • Mesothelioma / genetics
  • Mesothelioma / metabolism
  • Mesothelioma / pathology*
  • Microscopy, Electron
  • Middle Aged
  • Pleural Neoplasms / genetics
  • Pleural Neoplasms / metabolism
  • Pleural Neoplasms / pathology*
  • RNA, Viral / genetics
  • RNA, Viral / metabolism


  • Biomarkers, Tumor
  • RNA, Viral