Karyotyping of a hematologic neoplasia developing shortly after treatment for cerebral extragonadal germ cell tumor

Hematologic malignancies may be associated with mediastinal extragonadal germ cell tumors. It may be that the hematologic malignancy is a part of the natural history of the teratoma, one germ cell tumor line being able to differentiate into hematological cells, or the hematologic malignancy is related to the treatment, or the two malignancies develop independently. Cytogenetic analysis of bone marrow from a patient with a germ cell tumor in the brain and the almost simultaneous appearance of a hematologic neoplasia showed a rearranged karyotype in that all 15 analyzed cells had the same karyotype: 50,XY, +X, +del(1)(p21), +10, +11, -12, +der(12)t(12;?)(q?;?). Our findings were consistent with the interpretation that the hematologic malignancy was derived from the germ cell tumor.