Distinct clinical features of paraganglioma syndromes associated with SDHB and SDHD gene mutations.
BACKGROUND
Germline mutations of the genes encoding succinate dehydrogenase subunits B (SDHB) and D (SDHD) predispose to paraganglioma syndromes type 4 (PGL-4) and type 1 (PGL-1), respectively. In both syndromes, pheochromocytomas as well as head and neck paragangliomas occur; however, details for individual risks and other clinical characteristics are unknown.


OBJECTIVE
To determine the differences in clinical features in carriers of SDHB mutations and SDHD mutations.


METHODS
Population-based genetic screening for SDHB and SDHD germline mutations in 417 unrelated patients with adrenal or extra-adrenal abdominal or thoracic pheochromocytomas (n = 334) or head and neck paragangliomas (n = 83), but without syndromic features, from 2 registries based in Germany and central Poland, conducted from April 1, 2000, until May 15, 2004.


METHODS
Demographic and clinical findings with respect to gene mutation in SDHB vs SDHD compared with nonmutation carriers.


RESULTS
A total of 49 (12%) of 417 registrants carried SDHB or SDHD mutations. In addition, 28 SDHB and 23 SDHD mutation carriers were newly detected among relatives of these carriers. Comparison of 53 SDHB and 47 SDHD total mutation carriers showed similar ages at diagnosis but differences in penetrance and of tumor manifestations. Head and neck paragangliomas (10/32 vs 27/34, respectively, P<.001) and multifocal (9/32 vs 25/34, respectively, P<.001) tumors were more frequent in carriers of SDHD mutations. In contrast, SDHB mutation carriers have an increased frequency of malignant disease (11/32 vs 0/34, P<.001). Renal cell cancer was observed in 2 SDHB mutation carriers and papillary thyroid cancer in 1 SDHB mutation carrier and 1 SDHD mutation carrier.


CONCLUSIONS
In contrast with SDHD mutation carriers (PGL-1) who have more frequent multifocal paragangliomas, SDHB mutation carriers (PGL-4) are more likely to develop malignant disease and possibly extraparaganglial neoplasias, including renal cell and thyroid carcinomas. Appropriate and timely clinical screening is recommended in all patients with PGL-1 and PGL-4.
Department of Nephrology and Hypertension, Albert-Ludwigs-University, Freiburg, Germany. neumann@med1.ukl.uni-freiburg.de
Hartmut P H
HP
Neumann
Christian
C
Pawlu
Mariola
M
Peczkowska
Birke
B
Bausch
Sarah R
SR
McWhinney
Mihaela
M
Muresan
Mary
M
Buchta
Gerlind
G
Franke
Joachim
J
Klisch
Thorsten A
TA
Bley
Stefan
S
Hoegerle
Carsten C
CC
Boedeker
Giuseppe
G
Opocher
Jörg
J
Schipper
Andrzej
A
Januszewicz
Charis
C
Eng
D000008:Abdominal Neoplasms / Q000235:genetics; D000310:Adrenal Gland Neoplasms / Q000235:genetics; D000328:Adult; D000368:Aged; D005260:Female; D018095:Germ-Line Mutation; D005858:Germany; D006258:Head and Neck Neoplasms / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D007506:Iron-Sulfur Proteins; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008875:Middle Aged; D010235:Paraganglioma / Q000235:genetics*; D010673:Pheochromocytoma / Q000235:genetics*; D011044:Poland; D021122:Protein Subunits / Q000235:genetics*; D012042:Registries; D013385:Succinate Dehydrogenase / Q000235:genetics*; D013577:Syndrome; D013899:Thoracic Neoplasms / Q000235:genetics; D013964:Thyroid Neoplasms / Q000235:genetics
D007506:Iron-Sulfur Proteins; D008565:Membrane Proteins; D021122:Protein Subunits; C491545:SDHD protein, human; C108095:SDHB protein, human; D013385:Succinate Dehydrogenase