A 52-year-old man presents with bloody pleural effusion, left pleural thickening, and a history of asbestos exposure 30 years ago in a shipyard. Pleural biopsy shows malignant epithelioid cells staining positive for calretinin, WT-1, and D2-40, and negative for CEA and TTF-1. What is the diagnosis?

• A Metastatic adenocarcinoma of lung
• B Primary pleural lymphoma
• C Synovial sarcoma of pleura
• D Malignant pleural mesothelioma ✓

Explanation

Malignant pleural mesothelioma (MPM) is strongly associated with asbestos exposure with a latency of 20–40 years. The immunohistochemical profile — positive for calretinin, WT-1, and D2-40 (podoplanin), and negative for CEA and TTF-1 — is characteristic of epithelioid mesothelioma. Metastatic adenocarcinoma is CEA and TTF-1 positive. Lymphoma would be CD20/CD45 positive. This panel reliably distinguishes mesothelioma from pleural metastases.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.