Özyörük D, Kocayozgat A, Yaman-Bajin İ, Çetindağ F, Oğuz- Erdoğan AS, Güneş A. A 
synchronous occurrence of bifocal intracranial germinoma and bilateral 
testicular epidermoid cyst in an adolescent patient with Klinefelter`s syndrome. 
Turk J Pediatr 2019; 61: 456-459. Klinefelter syndrome (KS) is characterized by 
an additional X chromosome in males leading to a karyotype of 47,XXY. It is 
associated with an increased risk of certain malignancies, including leukemia, 
breast cancer and extragonadal germ cell tumor such as mediastinal germ cell 
tumors and rarely intracranial germ cell tumors. It is possible that the 
increased risk of developing certain cancers can be attributed to a direct 
effect of the chromosomal abnormality or the combined action of the abnormal 
chromosomes and hormonal imbalances. Here we describe a synchronous occurrence 
of bifocal intracranial germinoma and bilateral testicular epidermoid cyst in an 
adolescent patient with Klinefelter`s syndrome. The synchronous occurrence of 
the dual tumors in this patient with Klinefelter`s syndrome might be resulted 
from the migration defect during embriyogenesis due to underlying genetic 
disease or it is a coincidental condition, yet there has been no case reported 
in the literature, so far.