Comprehensive clinicopathologic characteristics of intraabdominal neurogenic tumors:Single institution experience

摘要

BACKGROUND Neurogenic tumors are rare but represent an important consideration in the differential diagnosis of abdominal mesenchymal tumors.Reports on their incidence,pathological features and clinical characteristics are scarce.AIM To advance the overall knowledge on the histologic,immunohistochemical,clinical and radiologic characteristics of neurogenic tumors through this case series.METHODS An established database of a nationwide tertiary referral center,covering a 15-year period(2005 and 2020),was retrospectively re-evaluated.Diagnoses of neurogenic tumor cases were confirmed by two experts following review of the macroscopic,histological and immunohistochemical records along with findings from analysis of archived tissue sections for each included patient.Tissue microarrays were constructed for cases lacking necessary immunohistochemical studies.Clinical data and follow-up information were collected from the hospital records and the patients themselves,when available.RESULTS The study included 19 cases of intraabdominal neurogenic tumors,representing 12 women and 7 men, between 18 and 86 years of age (median: 51 years). Finalconfirmed diagnoses were 12 schwannomas, 2 diffuse submucosal neurofibromatoses,2 ganglioneuromas, 2 malignant peripheral sheath nerve tumors,and 1 mucosal Schwann cell hamartoma. Sizes of the tumors were variable, with amedian diameter of 4 cm;the two largest (> 10 cm) were schwannomas. Themajority of cases were asymptomatic at presentation, but the most frequentsymptom was abdominal pain. Gastrointestinal tract lesions were detected withendoscopy and extra-luminal lesions were detected with cross-sectional imaging.All cases were S100-positive and CD117-negative;most cases were negative fordesmin, epithelial membrane antigen, smooth muscle actin and CD34. In all but 5cases, the Ki67 proliferation index was ≤ 1%.CONCLUSIONRe-evaluation of 19 cases of abdominal neurogenic tumors demonstrated considerablevariability in clinicopathologic characteristics depending on location,dimension and histological features.