Succinate dehydrogenase deficient gastrointestinal stromal tumor：a clinicopathologic analysis of eight cases
- VernacularTitle:琥珀酸脱氢酶缺陷型胃肠道间质瘤临床病理观察
- Author:
Qixing GONG
1
;
Weiming ZHANG
;
Hongxia LI
;
Beijing PAN
;
Zhihong ZHANG
Author Information
1. 210029,南京医科大学第一附属医院病理科
- Keywords:
Gastrointestinal stromal tumors;
Succinate dehydrogenase;
DNA mutational analysis;
Immunohistochemistry
- From:
Chinese Journal of Pathology
2015;(10):709-713
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the clinicopathologic features , diagnosis and differential diagnosis of succinate dehydrogenase ( SDH ) deficient gastrointestinal stromal tumors ( GISTs ) as a unique tumor subtype.Methods SDHB and SDHA immunohistochemistry was performed in 120 gastric GISTs, in addition to CD117, DOG-1, CD34, smooth muscle actin (SMA), desmin,S-100 protein, cytokeratin (CK) and Ki-67.Subset of the cases was further evaluated for the presence of mutations in CKIT exons 9, 11, 13 and 17 mutations and platelet derived growth factor receptor alpha ( PDGFRA) exons 12 and 18.Results Eight of 120 (6.6%) GIST cases were found SDH-deficient including 3 male and 5 female patients (median age of 36.2 years;ranging 16 to 65 years of age).The tumors involved antrum (6 cases), lesser curvature (1 case) and fundus (1 case).Macroscopically, the dominant tumor masses varied from 3 to 10 cm in diameter with a multinodular or plexiform pattern involving the gastric wall .Microscopically ,tumor cells had predominantly epithelioid morphology , with occasional mixed spindle cell nodules .Lymphovascular invasion was identified in 5 cases.Immunohistochemistry for SDHB was negative in all 8 cases, and SDHA was negative in 5 cases.All 8 SDHB negative cases also expressed CD 117, DOG-1 and CD34, but were negative for SMA, desmin, S-100 and CK.All 8 cases were found to have wild-type CKIT and PDGFRA genes. Available clinical follow-up were obtained in 7 cases, ranging from 2 to 60 months ( median follow-up 23.3 months) , and all patient were alive .Three cases were found to have liver metastases at their first diagnosis , and one developed omental and mesenteric metastases in 17 months.Conclusions SDH-deficient GIST is a distinct subtype of GIST , with a predilection to occur in young and female patients .Characteristic pathological findings include multinodular gastric wall involvement , epithelioid cell morphology , frequently lymphovascular invasion with occasional lymph node and liver metastases , but an overall indolent clinical behavior.Immunohistochemistry for SDHB is required for the diagnosis .
