Survival Outcomes of Patients With Primary Mediastinal Germ Cell Tumors: A Retrospective Single-institutional Experience.

BACKGROUND/AIM Primary mediastinal non-seminomatous germ cell tumors (PMNSGCTs) are occasionally complicated by a hematologic malignancy, as with somatic-type malignant tumors called germ cell tumors with somatic-type malignancy (GCTSTM) and are known to have a poor prognosis. PATIENTS AND METHODS Data obtained between September 1997 and February 2020 for patients with mediastinal germ cell tumor at our institution were retrospectively analyzed. Key outcome measures included survival rates and the clinical features of non-seminoma cases. RESULTS Of 16 patients, 9 had pure seminoma, and 7 had non-seminoma. At the median follow-up of 56.2 months, the 5-year survival rate was significantly higher in patients with seminoma (100%) than in those with non-seminoma (37%) (log-rank test, p=0.0153). Regarding PMNSGCT, two patients evolved into GCTSTM and three had concomitant hematological malignancies. CONCLUSION Patients with PMNSGCTs, GCTSTM complications, and hematologic malignancies showed poor survival, suggesting the need for the development of treatment strategies.