title: Colorectal cancer in a population with endemic Schistosoma mansoni: is this an at-risk population?
abstract: OBJECTIVE
  Chronic infection with schistosomiasis has been clearly associated with the development of bladder cancer, and infestation is associated with a high incidence of colorectal cancer in endemic populations. Despite this association, the potential role of alterations in tumor suppressor genes colorectal cancers has never been evaluated in an endemically infected population. The aim of this paper was to compare histopathologic and genetic changes in schistosomal colitis-associated colorectal cancer (SCC) with colorectal cancer in a group of patients from the same population not affected by the disease (NDCC).
  
  
  METHODS
  Sixty patients were included in this study: SCC-40, NDCC-20. Data collected included age, sex, clinical presentation, presence of synchronous tumors, histopathology, and clinical stage. p53, DCC (deleted in colorectal cancer gene), and mismatch repair genes (MLH1 and MSH2) were studied using immunohistochemical staining.
  
  
  RESULTS
  Patients with SCC were significantly younger than the NDCC group (34.52+/-11.22 years vs 50.73+/-12.75 years, p=0.02). Mucinous adenocarcinoma occurred significantly more frequently in SCC (35 vs 10%, p=0.02). SCC tumors were more frequently stage III or IV, and significantly more synchronous tumors were present in the affected group (SCC-8/40 vs NDCC-1/20, p=0.05). p53 staining was far more frequent in SCC (SCC-32/40 vs NDCC-8/20, p=0.006). DCC expression was similar in two groups. There were only four cases, three in SCC and one in NDCC, that showed microsatellite instability.
  
  
  CONCLUSIONS
  The data suggest that schistosomal colitis is more commonly associated with earlier onset of multicentric colorectal cancer, high percentage of mucinous adenocarcinoma, and presents at an advanced stage. The identification of a higher incidence of altered p53 expression in the SCC group raises the possibility of an association between schistosomiasis and alterations in p53 activation as an inciting event in colorectal cancer development.
authors.affiliation: Department of Surgery, University of Alexandria, Alexandria, Egypt.
authors.forename: Khaled M
authors.initials: KM
authors.lastname: Madbouly
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Senagore
authors.forename: Abir
authors.initials: A
authors.lastname: Mukerjee
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Hussien
authors.forename: M A
authors.initials: MA
authors.lastname: Shehata
authors.forename: Philippa
authors.initials: P
authors.lastname: Navine
authors.forename: Conor P
authors.initials: CP
authors.lastname: Delaney
authors.forename: Victor W
authors.initials: VW
authors.lastname: Fazio
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000469:parasitology*; D000328:Adult; D017668:Age of Onset; D000368:Aged; D003092:Colitis / Q000469:parasitology*; D015179:Colorectal Neoplasms / Q000235:genetics / Q000469:parasitology* / Q000473:pathology; D004534:Egypt; D019353:Endemic Diseases; D005260:Female; D015870:Gene Expression; D016163:Genes, DCC / Q000235:genetics; D016158:Genes, p53 / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012555:Schistosomiasis mansoni / Q000150:complications*; D012737:Sex Factors