Primary pulmonary lymphoepithelioma-like carcinoma accompanied by hypertrophic pulmonary osteoarthropathy in a non-epidemic region: a case report and literature review.

Pulmonary lymphatic epithelioma-like carcinoma (LELC) is a rare and unique subtype, accounting for 0.9% of all lung cancers. To date, just over 200 cases have been reported worldwide. The Epstein-Barr virus plays a role in the pathogenesis of LELC. Most patients are from East Asia, especially southeastern China. Chest computed tomography mainly shows a single lump or nodule around the lung. In this article, we report a 49-year-old male patient from a non-epidemic area who was hospitalized for "intermittent blood in his phlegm for more than 4 months". Imaging revealed two nodules in the left lower lobe of his lung. Transbronchial lung biopsy was performed on one of the nodules, and he was diagnosed with primary LELC. Single-photon emission computed tomography revealed that he had hypertrophic pulmonary osteoarthropathy, which is a rare symptom of paraneoplastic syndrome. Because the preoperative evaluation considered early-stage disease, video-assisted thoracoscopic surgery for the left lower lobe and mediastinal lymph node dissection were performed. Both lesions were eventually diagnosed as LELC. Fortunately, lymph node metastasis did not occur, and he did not receive other postoperative treatments. He was followed up for 1 year, and no recurrence was found.