title: Factors influencing outcome after surgery for stage IV colorectal cancer.
abstract: OBJECTIVE
  According to the classification system of the Japanese Society for Cancer of the Colon and Rectum, Stage IV colorectal cancer is characterized by distant metastasis, which is defined by four factors: liver metastasis (H factor), metastasis to organs other than the liver (M factor), peritoneal dissemination (P factor), and distant lymph node metastasis (N factor). We conducted this study to investigate the postsurgical prognosis of patients with Stage IV colorectal cancer (CRC), in reference to each of these four factors.
  
  
  METHODS
  We analyzed the medical records of 73 patients who underwent surgery for Stage IV CRC at our hospital between 1991 and 2001.
  
  
  RESULTS
  Univariate analysis revealed that P0 or P1 CRC (P < 0.001), absence of the M factor (P = 0.024), well or moderately differentiated adenocarcinoma (P < 0.001), resection of the primary tumor (P < 0.001), and curability B surgery (P < 0.0001) were associated with a better prognosis than other types of Stage IV CRC. Multivariate analysis revealed that tumor differentiation and surgical curability affected cancer-specific survival significantly.
  
  
  CONCLUSIONS
  Surgery with curative intent should be considered for patients with Stage IV CRC defined by the P1 factor or H factor.
authors.affiliation: Department of Surgical Oncology and Regulation of Organ Function, Miyazaki University School of Medicine, 5200 Kihara Kiyotake, Miyazaki, 889-1692, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hotokezaka
authors.forename: Sei-ichiro
authors.initials: S
authors.lastname: Jimi
authors.forename: Hideki
authors.initials: H
authors.lastname: Hidaka
authors.forename: Takuto
authors.initials: T
authors.lastname: Ikeda
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Uchiyama
authors.forename: Shinya
authors.initials: S
authors.lastname: Nakashima
authors.forename: Kazuyo
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Kazuo
authors.initials: K
authors.lastname: Chijiiwa