Germ-line mutations in nonsyndromic pheochromocytoma.

BACKGROUND: The group of susceptibility genes for pheochromocytoma that included the proto-oncogene RET (associated with multiple endocrine neoplasia type 2 [MEN-2]) and the tumor-suppressor gene VHL (associated with von Hippel-Lindau disease) now also encompasses the newly identified genes for succinate dehydrogenase subunit D (SDHD) and succinate dehydrogenase subunit B (SDHB), which predispose carriers to pheochromocytomas and glomus tumors. We used molecular tools to classify a large cohort of patients with pheochromocytoma with respect to the presence or absence of mutations of one of these four genes and to investigate the relevance of genetic analyses to clinical practice. METHODS: Peripheral blood from unrelated, consenting registry patients with pheochromocytoma was tested for mutations of RET, VHL, SDHD, and SDHB. Clinical data at first presentation and follow-up were evaluated. RESULTS: Among 271 patients who presented with nonsyndromic pheochromocytoma and without a family history of the disease, 66 (24 percent) were found to have mutations (mean age, 25 years; 32 men and 34 women). Of these 66, 30 had mutations of VHL, 13 of RET, 11 of SDHD, and 12 of SDHB. Younger age, multifocal tumors, and extraadrenal tumors were significantly associated with the presence of a mutation. However, among the 66 patients who were positive for mutations, only 21 had multifocal pheochromocytoma. Twenty-three (35 percent) presented after the age of 30 years, and 17 (8 percent) after the age of 40. Sixty-one (92 percent) of the patients with mutations were identified solely by molecular testing of VHL, RET, SDHD, and SDHB; these patients had no associated signs and symptoms at presentation. CONCLUSIONS: Almost one fourth of patients with apparently sporadic pheochromocytoma may be carriers of mutations; routine analysis for mutations of RET, VHL, SDHD, and SDHB is indicated to identify pheochromocytoma-associated syndromes that would otherwise be missed.

How many pathways to pheochromocytoma?

Pheochromocytomas, like several other tumors, may be either sporadic or the manifestation of a familial cancer syndrome. Recently, major advances have occurred in both the understanding of diverse molecular mechanisms leading to pheochromocytoma and the diagnostic modalities available for detection of the disease. Familial pheochromocytoma may be a manifestation of multiple endocrine neoplasia type 2 (MEN-2), von Hippel-Lindau (VHL), or neurofibromatosis-1 (NF 1) disease. Tumor-suppressor genes responsible for the familial occurrence of extra-adrenal pheochromocytoma, called paraganglioma, have been identified. This wealth of genetic information, coupled with the availability of sensitive and specific biochemical tests as well as imaging studies, allows for genetic screening and early diagnosis of pheochromocytoma. In addition, genetic screening of relatives at risk is now feasible. In this article, we review recent clinical and molecular advances in our understanding of pheochromocytoma.

Liver support--a task for nephrologists? Extracorporeal treatment of a patient with fulminant Wilson crisis.

BACKGROUND: Patients with Wilson's disease may present with cirrhosis, acute hepatitis or fulminant hepatic failure. Without urgent orthotopic liver transplantation, a fulminant Wilson crisis has a mortality of 100%. We report on an 18-year-old female patient with fulminant hepatic failure due to Wilson crisis. METHODS: The molecular adsorbent recirculating system (MARS) was used to eliminate albumin-bound toxins and to bridge waiting until an organ became available. RESULTS: A total of 18 MARS sessions and 4 plasma exchange sessions were performed. Bilirubin levels and hepatic encephalopathy improved under MARS therapy. A total of 75 mg copper was removed until serum copper levels were within the normal range. Copper elimination was measured in 15 MARS treatments, which removed a total of 12.9 mg copper. Four plasma exchange sessions, with a total exchange of 11 liters of plasma, removed 12 mg copper. Urinary copper elimination with penicillamine was 50 mg. CONCLUSION: MARS was an effective method to stabilize a patient with Wilson crisis, contributed to copper elimination and gained time for liver transplantation. The risk of high-urgency transplantation could be avoided. Liver support was easy in the hands of nephrologists familiar with extracorporeal therapy.

Pheochromocytomas: detection with 18F DOPA whole body PET--initial results..

PURPOSE: To evaluate fluorine 18 ((18)F) dihydroxyphenylalanine (DOPA) whole-body positron emission tomography (PET) as a biochemical imaging approach for detection of pheochromocytomas. MATERIALS AND METHODS: (18)F DOPA PET and magnetic resonance (MR) imaging were performed in 14 consecutive patients suspected of having pheochromocytomas (five sporadic, nine with von Hippel-Lindau disease); metaiodobenzylguanidine (MIBG) scintigraphy was performed in 12 of these patients. The individual imaging findings were assessed in consensus by specialists in nuclear medicine and radiologists blinded to the results of the other methods. The findings of the functional imaging methods were compared with those of MR imaging, the reference standard. Histologic verification could be obtained in eight patients with nine tumors. RESULTS: Seventeen pheochromocytomas (11 solitary, three bifocal; 14 adrenal, three extraadrenal) were detected with MR imaging. (18)F DOPA PET and MR imaging had concordant results in all 17 tumors. In contrast, MIBG scintigraphy had false-negative results in four patients with three adrenal tumors smaller than 2 cm and one extraadrenal tumor with a diameter of 3.6 cm. On the basis of these data, sensitivities of 100% for (18)F DOPA PET and of 71% for MIBG scintigraphy were calculated. Specificity was 100% for both procedures. CONCLUSION: (18)F DOPA PET is highly sensitive and specific for detection of pheochromocytomas and has potential as the functional imaging method of the future.