Gastrointestinal stromal tumors, intramural leiomyomas, and leiomyosarcomas in the duodenum: a clinicopathologic, immunohistochemical, and molecular genetic study of 167 cases

摘要: In this study we analyzed the clinicopathologic features of duodenal smooth muscle or stromal tumors, including 156 GISTs, 6 leiomyomas (LMs), and 5 leiomyosarcomas (LMSs) from files Armed Forces Institute Pathology Haartman University Helsinki. GISTs were documented as KIT positive (n = 109); 47 tumors also included because their histologic identity to KIT-positive cases. GIST-specific c-kit gene mutations in exon 11 9 30 cases (30%) 4 (13%). The occurred patients with an age range 10-88 years (median 56 years); 54% male. Ten had neurofibromatosis type I; six them multiple GISTs. ranged small asymptomatic intramural external nodules large masses that extended into retroperitoneum size 4.5 cm). They mostly spindle cell tumors; three malignant epithelioid morphology, 81 skeinoid fibers. often coexpressed CD34 (54%) variably for actin (39%) S-100 protein (20%) but never desmin. A total 86% >5 cm mitoses/50 high power fields (HPF) 21) died disease, whereas no tumor <2 <5 HPF 12) recurred caused death. Long latency was common between primary operation recurrences metastases; either one 49 140 follow-up (35%). No formula could accurately predict metastases, which occasionally developed even if mitotic activity <5/50 cm. Metastases abdominal cavity, liver, rarely bones lungs lymph nodes. Four actin- desmin-positive KIT-negative benign LMs similar those more seen esophagus. There five LMSs, formed a polypoid intraluminal mass; all negative. great majority mesenchymal are have spectrum indolent overt sarcomas. LMSs rare.