Medical Electron Microscopy

, Volume 36, Issue 3, pp 173–178

Desmoplastic malignant mesothelioma: two cases and a literature review

  • Hiroshi Hirano
  • Hajime Maeda
  • Noriyoshi Sawabata
  • Yoshitomo Okumura
  • Shinichi Takeda
  • Ryoji Maekura
  • Masami Ito
  • Tamaki Maeda
  • Shigeru Nakane
  • Kunio Uematsu
ORIGINAL PAPER

DOI: 10.1007/s00795-003-0217-0

Cite this article as:
Hirano, H., Maeda, H., Sawabata, N. et al. Med Electron Microsc (2003) 36: 173. doi:10.1007/s00795-003-0217-0

Abstract

We present two cases of desmoplastic malignant mesothelioma (DMM) with pathological, immunohistochemical, and ultrastructural features. Each patient showed rapid progress and died within 1 year from appearance of the initial symptoms. Macroscopically, both showed a thickened pleura replaced by a tumor that encased the lung. Microscopic results of each showed that the tumors consisted of a dense fibrous area, with mild nuclear irregularities and hyperchromatism. In case 1, the tumor had invaded the diaphragm, chest wall, and cardiac sac; the mass in case 2 invaded the lung and diaphragm, and distal metastases were seen in the thoracic vertebrae, meninges, and liver. Ultrastructural findings in case 1 showed a few short blunt microvilli on the cell surfaces. DMM is occasionally difficult to distinguish from fibrous pleurisy and solitary fibrous tumor. Immunohistochemical examinations of the present cases showed the expression of cytokeratin and vimentin, and focal positive stainings of antihuman mesothelial cell antibody (HBME-1) in both, whereas CD34 and bcl2 were negative. Solitary fibrous tumor was excluded. Therefore, pathological, ultrastructural, and immunohistochemical findings led us a diagnosis of DMM in each case. The Ki-67 labeling index (Ki-67 LI) of cases 1 and 2 was 25.5 and 15.5, respectively, both high, which suggested malignancy. Widespread immunohistological panels of malignant mesothelioma were not evaluated; Immunohistological markers commonly used for the diagnosis of malignant mesothelioma were not evaluated; however, the high ki-67 LI results and positive HBME-1 staining were helpful factors for the diagnoses of DMM.

Key words

Desmoplastic malignant mesotheliomaDifferential diagnosisImmunohistochemistryElectron microscopy

Copyright information

© Springer-Verlag Tokyo 2003

Authors and Affiliations

  • Hiroshi Hirano
    • 1
    • 2
  • Hajime Maeda
    • 3
  • Noriyoshi Sawabata
    • 3
  • Yoshitomo Okumura
    • 3
  • Shinichi Takeda
    • 3
  • Ryoji Maekura
    • 4
  • Masami Ito
    • 4
  • Tamaki Maeda
    • 5
  • Shigeru Nakane
    • 6
  • Kunio Uematsu
    • 1
  1. 1.Second Department of PathologyHyogo College of MedicineHyogoJapan
  2. 2.Division of PathologyToneyama National HospitalOsakaJapan
  3. 3.Division of SurgeryToneyama National HospitalOsakaJapan
  4. 4.Division of Internal MedicineToneyama National HospitalOsakaJapan
  5. 5.Department of TechnologyKobe Tokiwa CollegeHyogoJapan
  6. 6.Division of General Thoracic Surgery, Department of SurgeryOsaka University Graduate School of MedicineOsakaJapan