Neurofibromatosis type I-associated gastrointestinal stromal tumor:a clinicopathologic study of one case and review of the literature
YANG Ziyue
LI Zhengjin
Abstract：Objective: To improve the understanding of the pathological characteristics and diagnosis of gastrointestinal stromal tumor (GIST) associated with neurofibromatosis type I (NF1) by summarizing the clinical and pathological data of one case. Methods: A retrospective analysis was conducted on the clinical data, histopathology, immunohistochemistry, gene testing, and differential diagnosis of one NF1-related GIST, combined with relevant literature for summary. Results: The patient was a 68-year-old female, mainly presenting with black stools. Colonoscopy revealed multiple masses in the jejunum and multiple polyps in the colon. The skin had numerous scattered café-au-lait spots and nodules. The jejunal masses ranged in size from 0.2 to 1.5 cm, with gray-white solid cut surfaces and firm texture. Microscopically, the tumor was composed of spindle-shaped cells without mitotic figures. Immunohistochemical phenotype: CD117, CD34, SDHB, Vimentin, and Dog1 were positive; Ki-67 (<5% positive), CgA, CK-P, D2-40, Syn, and S-100 were negative. Mismatch repair proteins (MLH1, MSH2, MSH6, PMS2) were not deficient. Gene testing results: No mutations were detected in the c-kit gene exons 9, 11, 13, and 17; no mutations were found in PDGFRA gene exons 12 and 18. The abdominal skin nodule was a gray-white irregular tissue measuring 0.8 cm × 0.8 cm × 0.3 cm. Microscopically, the tumor cells were long spindle-shaped. Immunohistochemical phenotype: CD34, S-100, and SOX10 were positive; Ki-67 (<5% positive), Dog1, and CD117 were negative. Conclusion: NF1-related GIST is rare clinically and is a special type of GIST, representing a syndrome that combines the characteristics of neurofibromatosis type I and gastrointestinal stromal tumor. Diagnosis mainly relies on clinical manifestations, histopathological examination, immunohistochemistry, and gene testing.
Keywords：Neurofibromatosis Type I (NF1)-associated Gastrointestinal Stromal Tumor (GIST)Gastrointestinal Stromal TumorWild-typeNeurofibromatosis Type I
Publication Date：2025-12-28
Online Publishing Date：2026-01-28(First online date of this platform, not the publication date of the document)
Pages：5( 1687-1691 )