title: Granular cell tumours of the colorectum: histopathological and immunohistochemical evaluation of 30 cases.
abstract: OBJECTIVE
  Granular cell tumours (GCTs) are uncommon in the gastrointestinal tract, particularly in the colorectum. Herein, we report a series of 30 colorectal GCTs and discuss the properties of colorectal GCTs based on histopathological and immunohistochemical studies.
  
  
  RESULTS
  Searching the surgical pathology files identified 30 cases of colorectal GCTs for 2005-2013. A broad panel of antibodies including neural and macrophage markers were used for immunohistochemical evaluation. Colorectal GCTs predominantly involved the right colon and showed increased nuclear atypia including nuclear pleomorphism and nuclear spindling. All 24 cases with mucosal tumour components had infiltrative growth patterns within the mucosa. In all available cases, diffuse strong immunopositivity was observed for S100 and SOX10 of schwannian differentiation markers, as well as for CD68. Other neuronal lineage markers, including CD56, neuron-specific enolase, nestin, and synaptophysin showed consistently high expression rates. The immunohistochemical results are suggestive for a neural origin of GCTs.
  
  
  CONCLUSIONS
  Histopathological and immunohistochemical features of colorectal GCTs were delineated in this large series of 30 colorectal GCTs. Although the incidence of GCTs is relatively low, clinicians and pathologists need to be aware of GCT in the differential diagnosis.
authors.affiliation: Department of Pathology, Chonnam National University Medical School, Gwangju, Korea.
authors.forename: Jong-In
authors.initials: JI
authors.lastname: Na
authors.forename: Hye-Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jong-Jae
authors.initials: JJ
authors.lastname: Jung
authors.forename: Young
authors.initials: Y
authors.lastname: Kim
authors.forename: Sung-Sun
authors.initials: SS
authors.lastname: Kim
authors.forename: Jae-Hyuk
authors.initials: JH
authors.lastname: Lee
authors.forename: Kyung-Hwa
authors.initials: KH
authors.lastname: Lee
authors.forename: Jong-Tae
authors.initials: JT
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology*; D005260:Female; D016586:Granular Cell Tumor / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged
chemical_list: D014408:Biomarkers, Tumor
keywords: colorectal neoplasms; gastrointestinal tract; granular cell tumour; immunohistochemistry