Pleuroparenchymal sarcoidosis: A rare manifestation mimicking metastatic lung cancer

Our plain-English summary of Pleuroparenchymal sarcoidosis: A rare manifestation mimicking metastatic lung cancer, by E. Gan, C.K. Tay (Respirology Case Reports, 2024).

The study

• Authors: E. Gan, C.K. Tay
• Journal: Respirology Case Reports
• Published: 2024;12(8):e01438
• Type of article: Case report
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

A 66-year-old male from Myanmar presented with 3 months of cough and constitutional symptoms. He was an ex-tobacco user with no significant medical or exposure history. Chest x-ray showed ill-defined bilateral opacities and a left pleural effusion. Chest CT revealed two right lower lobe masses, and a moderate-sized left pleural effusion. PET-CT demonstrated hypermetabolic uptake in the thickened nodular pleura, pericardium, and hilar/mediastinal lymph nodes. EBUS-TBNA of the right lower paratracheal node and TBLB of the right lower lobe mass yielded epithelioid granulomas comprising multinucleated giant cells, epithelioid histiocytes and lymphoplasmacytic cells. Thoracoscopy revealed hard, whitish mass-like parietal pleural plaques, and pleural biopsy revealed identical histopathologic results. His symptoms resolved quickly after commencing prednisolone 25 mg daily. Chest CT at 6 months demonstrated near complete resolution of the parenchymal masses and pleural effusion. We highlight this unique case of pleuroparenchymal sarcoidosis mimicking metastatic lung cancer in a tuberculosis-endemic region.

© 2024 The Author(s). Respirology Case Reports published by John Wiley & Sons Australia, Ltd on behalf of The Asian Pacific Society of Respirology.

In plain English

This was a case report about one patient: a 66-year-old man from Myanmar with a 12 pack-year history of tobacco use. The article is about sarcoidosis, an inflammatory disease, and does not mention asbestos. The man denied any occupational dust exposure. He had 3 months of cough, breathlessness on exertion, poor appetite and weight loss. Scans showed masses in the right lung, nodules on the left pleura (the lining around the lung) and fluid around the left lung. The authors said this pattern mimicked lung cancer or tuberculosis. Tuberculosis tests were negative. Biopsies of a lymph node, the right lower lung and the left pleura showed non-necrotizing granulomas (clusters of inflammatory cells) and no cancer. At thoracoscopy, whitish mass-like nodular plaques were seen on the pleura, and biopsies of them showed the same granulomas. He was diagnosed with pleuroparenchymal sarcoidosis and given prednisolone 25 mg daily. His symptoms resolved within one month, and a CT scan at 6 months showed near-complete resolution. The authors concluded that the case shows how sarcoidosis can mimic lung cancer where tuberculosis is common.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (single patient)
• Who was studied: One 66-year-old man from Myanmar with previous tobacco use of 12 pack-years, who sought a second opinion at the authors' institution (Singapore General Hospital)
• Exposure: No asbestos exposure is described. The patient denied any occupational dust exposure and ran a trading business. The disease studied is sarcoidosis.
• Main results:
  • Initial pleural fluid cytology showed no malignant cells
  • Transbronchial lung biopsy of the right lower lobe showed non-necrotizing granulomatous inflammation with epithelioid histiocytes and multinucleated giant cells, without evidence of malignancy
  • Tests for tuberculosis were negative in sputum, bronchoalveolar lavage and lung biopsy samples
  • At thoracoscopy, whitish mass-like nodular plaques were seen on the parietal pleura and diaphragm. Left pleural biopsies showed non-necrotizing granulomatous inflammation, and no mycobacterial or fungal organisms were identified.
  • Based on consistent findings from multiple biopsy sites, the patient was diagnosed with pleuroparenchymal sarcoidosis and started on oral prednisolone 25 mg daily
  • Symptoms resolved one month after treatment began
  • Chest CT at 6 months after treatment showed near-complete resolution of the lung and pleural lesions and the left pleural effusion
• The authors' conclusion: The authors concluded that the case is a reminder of how sarcoidosis can mimic lung cancer in a tuberculosis-endemic region

Topics

Medical terms in this study, explained in our Lexicon: Lung Cancer, Exposure History, Chest X-Ray, Bilateral, Pleural Effusion, PET-CT, Pleura, Pericardium.

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