Clinicopathological Features of Primary Pulmonary Choriocarcinoma in Males: A Report of Two Cases and Literature Review

To investigate the clinicopathological characteristics, diagnosis, and treatment strategies of male primary pulmonary choriocarcinoma (PPC) and to enhance understanding of this rare disease. The clinicopathological data of two male PPC patients were retrospectively analyzed, and literature review was conducted to summarize epidemiological features, pathological mechanisms, and key diagnostic and therapeutic approaches. Case 1: A 14-year-old male presented with recurrent hemoptysis and dyspnea. CT revealed a right hilar mass suggestive of malignancy with multiple bilateral lung metastases. Case 2: A 71-year-old male presented with fatigue. CT identified a left lower hilar mass suspected to be lung cancer. PET-CT revealed a hypermetabolic soft-tissue mass in the left lower lobe. Two cases confirmed as PPC via biopsy. Case 1 died due to severe complications after treatment discontinuation. Case 2 received EMA/CO chemotherapy, which achieved normalized serum β-hCG levels and remained recurrence-free during follow-up 15 months. Literature review identified 68 PPC cases. Pathologically, tumors showed mixed proliferation of syncytiotrophoblasts and cytotrophoblasts with hemorrhagic background. Immunohistochemical markers hCG and CK7 were strongly positive. Treatment primarily involved surgery combined with platinum-based chemotherapy. Median survival was 15 months. Male PPC is extremely rare, particularly in elderly patients, and is often misdiagnosed as lung cancer or metastatic germ cell tumors. Serum hCG testing combined with pathological and immunohistochemical examinations is critical for diagnosis. Early surgery combined with multi-agent chemotherapy improves prognosis. These cases highlight the need to consider PPC in males presenting with solitary pulmonary lesions accompanied by metastases.