title: Clinical features of second other-site primary cancers among sporadic colorectal cancer patients--a hospital-based study of 3,722 cases.
abstract: OBJECTIVE
  Although synchronous and metachronous colorectal cancers are now well known to all colorectal surgeons, second other-site primary cancers following colorectal cancer are unfamiliar to most colorectal physicians. Knowledge of the clinical characteristics of these second other-site primary cancers becomes important especially during their follow-up surveillance.
  
  
  METHODS
  Information from a computer database was retrieved. Medical records were reviewed and all histopathological data were confirmed.
  
  
  RESULTS
  Forty-seven (1.26%) patients developed second other-site primary cancers. Of these patients, 22 (46.8%) patients were diagnosed concordantly while 25 (53.2%) patients were discordant cases. Twelve of 25 (45%) discordant cases were found within one year postoperatively. Regarding the clinical features of these 47 patients, male patients more frequently develop discordant cases (p=0.031). A significantly higher proportion of Dukes' B patients developed second other-site primary cancer than that of patients of other stages (p=0.017). Liver, 8 (17%) cases, was the most common site followed by the prostate, 6 (13%), stomach, 6 (13%), lung, 5 (11%), head and neck cancers, 5 (11%), and kidney, 3 (6.4%). However, there was not a significantly increased risk for these sporadic colorectal patients statistically.
  
  
  CONCLUSIONS
  We described clinical features of second other-site primary cancers and emphasized that knowledge of these is important for their postoperative surveillance.
authors.affiliation: Division of Colon and Rectal Surgery, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan. jmjiang@adm.cgmh.org.tw
authors.forename: Jy-Ming
authors.initials: JM
authors.lastname: Chiang
authors.forename: Chien-Yuh
authors.initials: CY
authors.lastname: Yeh
authors.forename: Chung Rong
authors.initials: CR
authors.lastname: Changehien
authors.forename: Jinn-Shiun
authors.initials: JS
authors.lastname: Chen
authors.forename: Reiping
authors.initials: R
authors.lastname: Tang
authors.forename: Wen-Sy
authors.initials: WS
authors.lastname: Tsai
authors.forename: Chung-Wei
authors.initials: CW
authors.lastname: Fan
mesh_terms: D003082:Colectomy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D011183:Postoperative Complications / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology / Q000601:surgery; D011336:Probability; D012042:Registries / Q000706:statistics & numerical data; D012306:Risk; D012737:Sex Factors; D013624:Taiwan