title: Validity of observation interval for synchronous hepatic metastases of colorectal cancer: changes in hepatic and extrahepatic metastatic foci.
abstract: BACKGROUND
  In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer maintains a strong influence on the metastases, so the possibility of occult hepatic and extrahepatic metastases must be kept in mind. Our treatment policy has been to reevaluate the metastases at an interval of 3 months after colorectal resection and determine treatment strategy. We examined the validity of observation interval for synchronous hepatic metastases.
  
  
  METHODS
  The treatment course was investigated for 36 patients with no extrahepatic lesion remnants at colorectal surgery and a simultaneously resectable liver (H1 group).
  
  
  RESULTS
  In the H1 group, eight patients underwent simultaneous colorectal and hepatic resections, while the treatment course for 28 patients was decided after an interval. Hepatic resection was not indicated in nine of the 28 patients during the interval. New lesions appeared during the interval in seven of 19 interval hepatic resection patients. In 16 (57%) of 28 interval patients, there was a change in the hepatic resection procedure or surgical indications.
  
  
  CONCLUSIONS
  Reevaluation after an observation interval allows accurate understanding of the number and location of hepatic metastases and is beneficial in determining candidates for surgery and in selecting treatment plan.
authors.affiliation: Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Kanokoden 1-1, Chikusa-ku, Nagoya, 464-8681, Japan. yshimizu@aichi-cc.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Kenzo
authors.initials: K
authors.lastname: Yasui
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Sano
authors.forename: Takashi
authors.initials: T
authors.lastname: Hirai
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Kanemitsu
authors.forename: Koji
authors.initials: K
authors.lastname: Komori
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Kato
mesh_terms: D003082:Colectomy; D015179:Colorectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D003131:Combined Modality Therapy; D018450:Disease Progression; D018572:Disease-Free Survival; D006498:Hepatectomy; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000556:secondary; D019370:Observation; D012086:Reoperation; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors