Clinicopathologic features and treatment of thymic lymphoepithelioma-like carcinoma: two case reports and literature review.

Lymphoepithelioma-like carcinoma (LELC) is rare in the thymus, and easily misdiagnosed. To improve its clinicopathologic knowledge, we describe two cases of thymic LELC, and investigate their microscopic and immunohistochemical features, treatment, and follow-up with a review of previously published cases. Two patients in the First Affiliated Hospital of China Medical University underwent complete surgical resection for thymic LELC. They were treated with chemotherapy or radiotherapy after operation. Histologically, tumor cells exhibited nest patterns or showed stripe-shaped infiltration in fibrous tissue containing lymphocytes. Tumor was diffusely positive for pan-cytokeratin (CK), CK19, cluster of differentiation 5 (CD5), CD117, epithelial membrane antigen (EMA), and p63, and negative for TdT. Recent follow-up showed that the two patients were alive with no signs of recurrence. We report two cases of thymic LELC with a review of previously published cases to summarize knowledge of their clinicopathological characteristics, which is necessary for accurate diagnosis and clinical treatment.