title: [Synchronous neoplasias in colorectal cancer].
abstract: OBJECTIVE
  The aim of this study was to show the incidence of synchronous lesions in colorectal cancer patients treated surgical at our service.
  
  
  BACKGROUND
  Many studies have shown different incidences of synchronous lesions in colorectal cancer, mainly due to variations in the accuracy of the diagnostic methods used and the intentional search for associated lesucosal.
  
  
  METHODS
  Fifty-eight clinical records of patients operated on for colorectal cancer were retrospectively reviewed from August 1995 to March 1999. The synchronous lesions were classified as benign or malignant lesions based on its histological classification. Statistical analysis was carried out by the Spearman coefficient correlation.
  
  
  RESULTS
  Fifteen patients (25.8%) had 28 synchronous lesions, nine were male (60%), and six females (20%). The average age was 63.2 years with a range of 26 to 83 years. The endoscopic diagnosis of synchronous lesions was performed preoperatively in 12 patients (80%). The most frequent localization's of primary tumor was the sigmoid colon in six patients (40%). The more frequent localization of synchronous lesions was the rectum (35.7%). Benign lesions were most commonly found in synchronous lesions (89.3%).
  
  
  CONCLUSIONS
  The patient with colorectal cancer has an unstable epithelium and an uncommon predisposition to develop several mucosal alterations. This predisposition is prone to grow benign or malignant lesions. For this reason, we advise all that patient with colorectal cancer be fully studied endoscopically.
authors.affiliation: Departamento de Cirugía de Colon y Recto del Hospital de Especialidades del Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México, D.F.
authors.forename: E E
authors.initials: EE
authors.lastname: Geminiano-Martínez
authors.forename: J P
authors.initials: JP
authors.lastname: Peña Ruíz-Esparza
authors.forename: E
authors.initials: E
authors.lastname: Villanueva-Sáenz
authors.forename: J F
authors.initials: JF
authors.lastname: Alvarez-Tostado Fernández
authors.forename: M
authors.initials: M
authors.lastname: Arenas-Sánchez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology*; D012189:Retrospective Studies