title: Incidence of synchronous appendiceal neoplasm in patients with colorectal cancer and its clinical significance.
abstract: BACKGROUND
  The aims of this study were to evaluate the incidence of synchronous appendiceal neoplasm in patients with colorectal cancer, and to determine its clinical significance.
  
  
  METHODS
  Pathological reports and medical records were reviewed of patients with colorectal adenocarcinoma who underwent oncological resection of the tumor together with appendectomy at the Faculty of Medicine Siriraj Hospital, Mahidol University, Thailand between September 2000 and April 2008.
  
  
  RESULTS
  This study included 293 patients with an average age of 62 years (range 19-95) and 51 percent were male. Of the patients studied, 228 (78 percent) had right hemicolectomy, whereas the others (22 percent) had surgery for left-sided colon cancer or rectal cancer. One patient (0.3 percent) had epithelial appendiceal neoplasm (mucinous cystadenoma) and 3 patients (1.0 percent) had metastatic colorectal cancer in the mesoappendix. However, the presence of synchronous appendiceal tumors and/or metastasis did not alter postoperative management, as these patients had received adjuvant therapy and were scheduled for surveillance program because of nodal involvement.
  
  
  CONCLUSIONS
  The incidence of synchronous primary appendiceal neoplasm and secondary (metastatic) appendiceal neoplasm in colorectal cancer patients was 0.3 and 1.0 percent, respectively. However, these findings did not change the postoperative clinical management.
authors.affiliation: Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. bolloon@hotmail.com
authors.forename: Varut
authors.initials: V
authors.lastname: Lohsiriwat
authors.forename: Akkrarash
authors.initials: A
authors.lastname: Vongjirad
authors.forename: Darin
authors.initials: D
authors.lastname: Lohsiriwat
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001063:Appendiceal Neoplasms / Q000453:epidemiology*; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology*