[Characteristics of non-small cell lung carcinoma with trophoblastic differentiation in males: a clinicopathological analysis of 16 cases].

Abstract

Objective: To investigate the clinical pathological features, immunophenotypes, diagnosis, and differential diagnosis of non-small cell lung carcinoma (NSCLC) with trophoblastic differentiation in males, and to improve the understanding of this rare disease. Methods: The clinical and pathological features of 16 NSCLC with trophoblastic differentiation in males diagnosed in Shanghai Pulmonary Hospital from January 2017 to December 2023 were retrospectively analyzed. Relevant literature was reviewed. Results: All 16 patients were male, with an onset median age of 66.5 (56.8, 68.8) years. They had no known personal history of cancer. Among the 8 resected NSCLC with trophoblastic differentiation, 3 showed concurrent lung adenocarcinoma, and 1 showed concurrent lung squamous cell carcinoma. Among the 10 patients who underwent serum β human chorionic gonadotropin (β-HCG) testing after the surgery or biopsy, 7 had significantly increased β-HCG. On gross examination, the tumors were hemorrhagic and necrotic, resembling a hematoma, with a medium texture, clear boundaries and no capsules. At low magnification, tumor cells were arranged in a nested or solid pattern. Those cells often showed massive bleeding, necrosis, and vascular infiltration. They were composed of two types of cells, namely cytotrophoblast and syncytiotrophoblast cells. At high magnification, the tumor cells showed large nuclei and hyperchromatia. They also had rich purple blue to bichromatic cytoplasm, eosinophilic nucleoli, and sometimes bizarre nuclei. The syncytiotrophoblast cells expressed β-HCG, CKpan, GATA3, CD10, and SALL4. Fourteen patients were followed up for 1-37 months. Two of them died, while three showed distant metastasis. Conclusions: NSCLC with trophoblastic differentiation in males is a rare and highly malignant tumor, poorly understood with difficulty in diagnosis. It requires comprehensive histological analysis in combination with clinical and imaging studies. Properly diagnosing this disease relies on recognition of its histopathological characteristics, including large areas of bleeding and necrosis, large and peculiar syncytial trophoblast cells, and varying degrees of β-HCG expression. It seems that β-HCG expression is very valuable for diagnosing this rare tumor.