[Multiple Minute Pulmonary Meningothelial-like Nodules;Report of a Case]

A 57-year-old woman was referred to our hospital for investigation of multiple tiny nodules in the lung fields bilaterally on computed tomography (CT). Video-assisted thoracoscopic lung biopsy was performed to diagnose the pulmonary lesions. Histological analysis showed nodular lesions with interstitial proliferation of uniform, round to oval cells with variable widening of the alveolar septa. Immunohistochemically, the cells were positive for EMA, CD56 and the progesterone receptor, but negative for chromogranin and synaptophysin. The diagnosis was "diffuse pulmonary meningotheliomatosis", with multiple diffuse "minute pulmonary meningothelial-like nodules". Diffuse pulmonary meningotheliomatosis should be kept in mind when we encounter small nodular shadows on a CT scan.