Objective: The aim of this study was to evaluate the clinical characteristics and survival outcomes of patients with primary mediastinal germ cell tumor (PMGCT) by identifying the prognostic factors and efficacies of different treatment modalities.
Methods: Fifty-five patients with PMGCT who were treated consecutively at Cancer Center, Sun Yat-sen University, Guangzhou, from 1988 to 2010 were evaluated retrospectively.
Results: Fifty-two men and 3 women with a median age of 25 years were identified, of whom 17 (30.9%) had pure seminomatous, 38 (69.1%) had nonseminomatous histology, 27 (49.1%) had tumor located at mediastinum, 20 (36.4%) had lung metastases and/or effusions, and 8 (14.5%) had distant metastases. Three treatments surgery, chemotherapy, and radiotherapy were performed in 11 (20%) patients, two treatments chemotherapy plus surgery or radiotherapy were performed in 25 (45.6%), and single treatment surgery or chemotherapy was performed in 17 (30.9%). The other two patients (3.6%) received no treatment. After a median follow-up time of 31.4 months, the 5-year survival rate was 52%. The median overall survival time was 87.9 months. Patients who received two treatments had the longest survival time of 118.3 months, P = 0.000. Those who had pure seminoma histology, whose tumor confined to the mediastinum and who achieved complete or partial remission at initial evaluation, who had complete resection and radiotherapy were considered to have better prognosis according to univariate analysis. On multivariate analysis, extension and response rate at initial evaluation were independently predictive of survival.
Conclusions: Primary mediastinal germ cell tumor is rare with a dominant frequency in young male patients. Chemotherapy combined with local therapy like surgery or radiotherapy is a reasonable treatment strategy recommended. Extension and initial remission rate are independent prognostic factors.