Utility of Site-Specific Biopsy for Diagnosis of Desmoplastic Malignant Mesothelioma

Desmoplastic malignant mesothelioma (DMM) is a relatively rare histologic subtype of malignant pleural mesothelioma (MPM). Among MPMs, the diagnosis of DMM is particularly difficult because the tumor is largely composed of dense hyalinized fibrous stroma and few malignant cells. We present two cases of DMM, one in a 47-year-old man and the other in a 64-year-old man. From detailed pathologic findings in these two cases, we conclude that cases of DMM that cannot otherwise be diagnosed with the use of conventional pleural biopsy, may be diagnosed successfully with the use of wedge lung resection.