Primary Pulmonary Perivascular Epithelioid Cell Tumour ( PEComa ): A Case Report

Perivascular epithelioid cell tumour (PEComa) is a rare mesenchymal neoplasm; lung is an exceptional primary site. Herein, we present a surgically resected case of primary pulmonary PEComa and discuss its clinicopathologic features in comparison with previously published cases. A 47‐year‐old woman presented with a screening‐detected right lower lobe nodule. Computed tomography showed a 26‐mm S6 lesion abutting the A6. The patient underwent right S6 segmentectomy for diagnosis and treatment. The 30‐mm mass was well demarcated and pearly white; histology showed epithelioid cells with sinusoid‐like vasculature, rare mitoses and no necrosis. HMB45/Melan‐A was positive for focal smooth muscle actin, confirming the diagnosis of PEComa. The patient remained disease free for > 1 year under observation without adjuvant therapy. Although primary pulmonary PEComa is rare and typically indolent, reports of malignant behaviour justify vigilant long‐term surveillance and further case accumulation is warranted to refine the diagnostic criteria and management strategies.