RESUMO
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.
