SDHB and metastatic malignant neoplasm in the lymph nodes: Genetic testing was performed on 45 patients in the lymph node metastasis group, and 33 patients (73.3%) had KIT gene mutations, including 25 patients with KIT 11 mutations and 9 patients with KIT 8 mutations; 12 patients (26.7%) had wild-type GIST, of whom 4 patients had SDHB-deficient GIST.