title: Medullary carcinoma of the small bowel.
abstract: OBJECTIVE
  Medullary carcinoma of the large bowel occurs mainly right-sided in elderly females. The tumour is almost invariably microsatellite instable and has been associated with favourable outcome. Our study aimed to present three cases of medullary carcinoma originating from the small bowel.
  
  
  RESULTS
  We describe three cases of small bowel medullary carcinoma. Two patients had coeliac disease, diagnosed at the ages of 79 and 71 years, respectively. The tumours showed the characteristic syncytial growth pattern with marked intratumoral lymphocytic inflammation. Loss of MutL homologue 1 (MLH1) [and postmeiotic segregation increased 2 (S. cerevisiae) PMS2] expression was observed in all cases, consistent with high-level microsatellite instability. All tumours were negative for Epstein-Barr virus. Follow-up information was available for one patient, who is recurrence-free 6 years after resection.
  
  
  CONCLUSIONS
  Medullary carcinoma of the small bowel is exceedingly rare. Our data and a review of the literature suggest that this tumour type is characteristic for coeliac disease and may be the histological type underlying small bowel cancers with high-level microsatellite instability in patients with coeliac disease.
authors.affiliation: Institute of Pathology, Medical University of Graz, Graz, Austria.
authors.forename: Iva
authors.initials: I
authors.lastname: Brcic
authors.affiliation: Institute of Pathology, Kantonsspital Baselland, Liestal, Switzerland.
authors.forename: Gieri
authors.initials: G
authors.lastname: Cathomas
authors.affiliation: Department of Molecular Medicine, San Matteo Hospital, University of Pavia, Pavia, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Vanoli
authors.affiliation: Department of Internal Medicine, LKH Hochsteiermark, Leoben, Austria.
authors.forename: Kurt
authors.initials: K
authors.lastname: Jilek
authors.affiliation: First Department of Internal Medicine, San Matteo Hospital, University of Pavia, Pavia, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Giuffrida
authors.affiliation: Institute of Pathology, Medical University of Graz, Graz, Austria.
authors.forename: Cord
authors.initials: C
authors.lastname: Langner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018276:Carcinoma, Medullary / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D002446:Celiac Disease / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D007414:Intestinal Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism / Q000473:pathology; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged
keywords: coeliac disease; ileum; jejunum; medullary carcinoma; microsatellite instability