Hematologic disorders associated with primary mediastinal nonseminomatous germ cell tumors

Background. The association between primary germ cell tumors of the mediast inum (the space between the lung pleura that contains the heart and other c hest viscera) and hematologic malignancies has been described by retrospect ive analysis of patients treated at individual clinical centers. To better characterize the risk of hematologic disorders in patients with extragonada l germ cell tumors and to describe the clinical and biologic features of th e disorders, we studied an unselected population in a large, international, multicenter database. Methods. Six hundred thirty-five patients treated at . II centers in the United States and Europe from 1975 through 1996 were ev aluated retrospectively. Results. A hematologic disorder was observed in 17 patients with germ cell tumors. All cases developed among the 287 patients with primary mediastinal nonseminomatous germ cell tumors, giving an incid ence rate in this group of 2.0% (95% confidence interval [CI] = 1.1%-3.1.%) per year over a median follow-up time of 3 years. The risk of developing h ematologic disorders was statistically significantly increased in patients with primary mediastinal nonseminomatous germ cell tumors in comparison wit h the age-matched general population (standardized incidence ratio = 250; 9 5% CI = 140-405), The median time to onset of hematologic neoplasia was 6 m onths (range, 0-47 months), and the median survival after diagnosis of the hematologic disorder was 5 months (range, 0-16 months) (two-sided P < .0001 , comparing survival from the time of diagnosis of the germ cell tumor of p atients with and without hematologic disorders). Conclusion. In our study, approximately one in 17 patients with primary mediastinal nonseminomatous g erm cell tumors was affected by a hematologic disorder, whereas no cases we re seen among 334 patients with other extragonadal germ cell tumors, The he matologic disorder had a statistically significant impact on prognosis, wit h none of the 17 reported patients surviving for more than 2 years.