Duodenal GIST: a single center experience

Abstract

Purpose: The duodenum as primary site for gastrointestinal stromal tumors (GISTs) is rare and mitotic rate, tumor size, type of mutation and number of chromosomal aberrations have prognostic implications.

Methods: We analyzed the outcome of 13 patients with duodenal GISTs who underwent surgical tumor resection. Either segmental duodenectomy or pylorus-preserving duodenopancreatectomy was performed. The tumors were histopathologically examined and the risk of progression was assessed based on tumor size and mitotic count. Additionally, mutation analysis of the KIT and PDGFRA receptor tyrosine kinase genes and comparative genomic hybridization (CGH) were performed in all cases.

Results: Eight patients underwent segmental duodenectomy and five patients were treated with pylorus-preserving duodenopancreatectomy. None of the five GISTs with low or no risk for malignancy according to the Miettinen classification developed tumor progress. In contrast, five of eight cases (62.5%) with high-risk tumors revealed tumor progress, and four of these patients died (50%). The median overall survival for all patients was 66 months, and the median disease-free survival 41 months. The operative procedure and type of mutation did not correlate with long-term survival. CGH analysis displayed -15q in 12/13 tumors, and -1p in 11/13 cases as characteristic chromosomal aberrations for intestinal origin. Notably, -22q was present in three of four cases with tumor progress.

Conclusions: Both segmental duodenectomy and pylorus-preserving duodenopancreatectomy are appropriate options to treat duodenal GIST and should be implemented depending on resectability and the patient's performing state. The Miettinen classification and CGH findings correlate with the clinical course.

Fig. 1

Morphologic findings in a case of duodenal GIST (patient 12): endoscopy revealed a submucosal mass lesion in the duodenum covered by normal duodenal mucosa (a arrow). Grossly, the tumor measured up to 2.5 cm in size with sharply defined margins and a pale-white, solid cut surface (b). Histologically, the tumor was of spindle cell differentiation without cellular atypia (c hematoxylin–eosin stain) and showed marked expression of CD117 (cKIT, d) (×100)

Fig. 2

Kaplan–Meier estimator demonstrates overall (a) and disease-free survival (b) for the 13 patients with duodenal GIST

Fig. 3

Kaplan–Meier estimator shows the overall survival (a) and disease-free survival (b) for the 13 patients with duodenal GIST comparing segmental duodenectomy vs. duodenopancreatectomy

Fig. 4

Kaplan–Meier estimator demonstrates overall survival for the 13 patients with duodenal GIST comparing low-risk vs. high-risk duodenal GIST

Fig. 5

Results of KIT exon 9, 11, 13, and 17 and PDGFRA exon 12, 14, and 18 mutation analyses in 13 duodenal gastrointestinal stromal tumors

Fig. 6

Chromosomal imbalances in 13 duodenal gastrointestinal stromal tumors as detected by comparative genomic hybridization are shown as bright gray (gains), black (losses), and dark gray bars (amplifications) for each chromosome. Losses at 1p, 15q, and 22q are among the most frequently observed aberrations

Fig. 7

Kaplan–Meier estimator demonstrates overall survival for the 13 patients with duodenal GIST comparing the cases with ≤5 and >5 chromosomal losses as detected by comparative genomic hybridization