SDHC and paraganglioma: SDH-deficient GISTs are more commonly seen in pediatric patients and can be associated with either the Carney triad (GIST, paraganglioma, pulmonary chondroma) characterized by epigenetic silencing of the SDHC gene by the promoter hypermethylation or Carney–Stratakis syndrome (GIST and paraganglioma), which are caused by germline mutations in SDH [14,15,16,17].