title: [Unsuspected tumor of the colon].
abstract: BACKGROUND
  Occasionally, an unexpected colonic mass is seen during surgery and for its characteristics it is difficult to distinguish if the lesion is benign or malignant; the surgeon must define resection or realize complementary clinical and histopathological studies for the final diagnosis which allows to offer adequate treatment.
  
  
  OBJECTIVE
  To present our experience of patients with unexpected colonic mass during abdominal surgery. We analyze clinic course and definitive pathologic diagnostic.
  
  
  METHODS
  We reviewed 8,703 files of patients with abdominal surgery, 21 (0.24%) presented an unexpected colonic tumor. Patients were divided in two groups: the group I were studied without initial resection; group II included patients that were treated with resection.
  
  
  RESULTS
  In patients without initial resection (n = 16) 11 required definitive resection in an average of twelve days, no complications were noted between the initial and definitive surgery; in remaining 5 patients final diagnostic was ameboma which responded well to medical treatment. In patients of group II(n = 5), in three of them complications were present.
  
  
  CONCLUSIONS
  In our country ameboma must be considered in the differential diagnosis of colonic tumors, no required resection. Therefore, discovery of unexpected colonic mass during surgery, justifies to realize complementary studies before resection.
authors.affiliation: Servicio de Cirugía General del Hospital General Regional Núm. Instituto Mexicano del Seguro Social, México, D.F.
authors.forename: G
authors.initials: G
authors.lastname: Guzmán Valdivia Gómez
authors.forename: M
authors.initials: M
authors.lastname: Chavelas Lluck
authors.forename: E
authors.initials: E
authors.lastname: Medina González
mesh_terms: D000208:Acute Disease; D000230:Adenocarcinoma / Q000175:diagnosis / Q000601:surgery; D000328:Adult; D000368:Aged; D000562:Amebiasis / Q000175:diagnosis; D001064:Appendicitis / Q000175:diagnosis; D002430:Cecal Neoplasms / Q000175:diagnosis / Q000601:surgery; D003082:Colectomy; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000601:surgery; D003937:Diagnosis, Differential; D004238:Diverticulitis / Q000175:diagnosis; D005260:Female; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012811:Sigmoid Neoplasms / Q000175:diagnosis / Q000601:surgery
vernacular_title: Tumor insospechado en el colon.