title: Congenital gastrointestinal stromal tumour is morphologically indistinguishable from the adult form, but does not express CD117 and carries a favourable prognosis.
abstract: OBJECTIVE
  The histological and immunohistochemical features of a congenital stromal tumour of the jejunum are compared with those of adult gastrointestinal stromal tumours (GIST). The literature concerning the diagnosis and prognosis of congenital small intestinal stromal tumours is reviewed.
  
  
  RESULTS
  A term female infant presented with intestinal obstruction, from birth. Histology of a 15-mm jejunal nodule showed a predominantly spindle-cell tumour with epithelioid areas. There was a low mitotic count and mild nuclear pleomorphism, extensive necrosis and haemorrhage, and focal calcification. Immunohistochemically, tumour cells stained for muscle specific actin and vimentin. Staining for CD117 (c-kit), S100, desmin and CD34 was negative. The features were compared to those of seven adult cases: no morphological feature was specific to the congenital tumour, which was smaller than the adult cases. There were no ultrastructural features specific for a particular line of differentiation. Immunohistochemical staining patterns were similar, except for CD117, which was strongly positive in all adult tumours, but negative in the congenital tumour.
  
  
  CONCLUSIONS
  This congenital jejunal stromal tumour morphologically resembled adult GIST, but lack of c-kit expression suggests that it is nosologically distinct. Despite the presence of histological features which would cause the tumour to be categorized as malignant in an adult, it is apparent from previous reports of congenital small intestinal stromal tumours that the prognosis is favourable.
authors.affiliation: Department of Histopathology and Morbid Anatomy, Institute of Pathology, The Royal London Hospital, London, UK.
authors.forename: A W
authors.initials: AW
authors.lastname: Bates
authors.forename: R M
authors.initials: RM
authors.lastname: Feakins
authors.forename: I
authors.initials: I
authors.lastname: Scheimberg
mesh_terms: D000199:Actins / Q000032:analysis; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000151:congenital / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D007231:Infant, Newborn; D007580:Jejunal Neoplasms / Q000151:congenital / Q000378:metabolism / Q000473:pathology; D007583:Jejunum / Q000737:chemistry / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000737:chemistry; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis*; D014746:Vimentin / Q000032:analysis
chemical_list: D000199:Actins; D014746:Vimentin; D019009:Proto-Oncogene Proteins c-kit