Role of rapid sequence whole-body MRI screening in SDH-associated hereditary paraganglioma families
Kory W Jasperson1, Wendy Kohlmann, Amanda Gammon
1Huntsman Cancer Institute, University of Utah, 2000 Circle of Hope, Rm 1166, Salt Lake City, UT, 84112, USA, kory.jasperson@hci.utah.edu.
Abstract:
Patients with germline mutations in one of the SDH genes are at substantially increased risk of developing paragangliomas, pheochromocytomas (pheos), and other tumors (all combined referred to as SDH-related tumors). However, limited data exist on screening in SDH mutation carriers and no studies have evaluated whole-body MRI as a screening tool in asymptomatic patients. This was a single-center observational study. We evaluated the results of screening in 37 SDH carriers who underwent 45 whole-body MRIs and 47 biochemical tests. Screening included annual biochemical testing (catecholamines, metanephrines and chromogranin A) and biennial or annual rapid sequence whole-body MRI from the base of the skull to the pelvis beginning at age 10 years old. Six tumors (paragangliomas of the organ of Zuckerkandl, the aortocaval/vas deferens, of the carotid body times three, and a renal cell carcinoma) were diagnosed in five patients. In total, 13.5 % of all patients screened were diagnosed with SDH-related tumors. Whole-body MRI missed one tumor, while biochemical testing was normal in five patients with SDH-related tumors. The sensitivity of whole-body MRI was 87.5 % and the specificity was 94.7 %, while the sensitivity of biochemical testing was 37.5 % and the specificity was 94.9 %. Whole-body MRI had a higher sensitivity for SDH-related tumors than biochemical testing in patients undergoing screening due to their SDHB or SDHC mutation status. Whole-body MRI reduces radiation exposure compared to computed tomography scan and time compared to dedicated MRI of the head/neck, thorax, and abdomen/pelvis.
Insights
Whole-body MRI shows higher sensitivity for detecting SDH-related tumors in mutation carriers compared to biochemical tests. This screening method aids in early diagnosis of paragangliomas and pheochromocytomas.
Area of Science:
- Oncology
- Genetics
- Radiology
Background:
- Germline mutations in succinate dehydrogenase (SDH) genes significantly increase the risk of developing SDH-related tumors, including paragangliomas and pheochromocytomas.
- Limited data exist on effective screening protocols for SDH mutation carriers, and whole-body MRI has not been evaluated as a primary screening tool in asymptomatic individuals.
Purpose of the Study:
- To evaluate the efficacy of whole-body MRI as a screening tool for SDH-related tumors in asymptomatic SDH gene mutation carriers.
- To compare the sensitivity and specificity of whole-body MRI with biochemical testing for detecting these tumors.
Main Methods:
- A single-center observational study involving 37 SDH carriers who underwent 45 whole-body MRIs and 47 biochemical tests.
- Screening protocol included annual biochemical testing (catecholamines, metanephrines, chromogranin A) and biennial or annual rapid sequence whole-body MRI from skull base to pelvis, starting at age 10.
Main Results:
- Six SDH-related tumors were diagnosed in five patients (13.5% of screened patients), including paragangliomas and a renal cell carcinoma.
- Whole-body MRI demonstrated a sensitivity of 87.5% and specificity of 94.7%, detecting 7 out of 8 tumors.
- Biochemical testing showed a sensitivity of 37.5% and specificity of 94.9%, missing five tumors.
Conclusions:
- Whole-body MRI is a more sensitive screening tool for SDH-related tumors than biochemical testing in SDH mutation carriers.
- Whole-body MRI offers reduced radiation exposure compared to CT scans and is more time-efficient than dedicated MRIs of multiple body regions.
