Introduction: Desmoplastic Malignant Mesothelioma (DMM) is a rare histological subtype of sarcomatoid malignant mesothelioma arising most frequently in the pleura or peritoneum and less frequently in the lung parenchyma.
Patient concerns: A 52-year-old female with no apparent asbestos exposure was referred for consultation in our center after 1 month of cough and no concomitant symptoms of chest.
Diagnosis: Chest computed Tomography (CT) revealed a localized mass measuring 4.5 x 3.9 cm in the right lung middle lobe with inhomogeneous enhancement following injection of contrast, and without pleural lesions, considered a primary intrapulmonary desmoplastic mesothelioma.
Interventions: Surgical intervention was performed.
Outcomes: Following complete tumor resection, the patient declined to receive chemotherapy or radiotherapy. The final diagnosis of intrapulmonary desmoplastic mesothelioma was confirmed by pathological and immunohistochemical examination. In addition, no local tumor recurrence was observed within 10 months of follow-up.
Conclusion: Even elderly female patients with localized pulmonary masses without significant pleural lesions should not excluded the possibility of malignant mesothelioma in the lungs.