2010 Volume 10 Issue 1 Pages 6-12
Great progress has been achieved in the fields, especially genetics in pheochromocytoma. Before 2000, 10% of patients were believed to have a hereditary disease. After 2000, however, around 30% of pheochromocytoma patients assumed to have a hereditary disease following reason. 1）Nuclear genes encoding two mitochondrial complex II subunit proteins, SDHD and SDHB, have been found to be associated with the development of familial pheochromocytomas and paragangliomas（ Hereditary pheochromocytoma/ paraganglioma syndrome）, in 5% of familial cases. respectively. 2）It is reported that 10% of apparently sporadic patients have unexpected germline mutation. Also, growing evidence suggest that mutation of SDHB is highly associated with abdominal paraganglioma and the following distant metastasis. However, these findings were obtained mainly from USA and Europe. Therefore, it remains uncertain whether these genes play a pathological role in populations outside these geographic locations. To overcome this problem, we set up multi-institute studies to determine diagnostic value of genetic testing in our country. In the present study, analysis of blood taken from 25 cases of malignant pheochromocytomas in Japanese subjects （13 abdominal paraganglioma and 12 adrenal pheochromocytomas） led to the identification of nine SDHB mutations. It should be noted that 7 SDHB mutations were detected in 13 abdominal paraganglioma-derived malignant cases （7/13）, whereas 2 SDHB mutation was observed in 10 malignant cases derived from adrenal pheochromocytoma （2/10）, in agreement with previous reports.
