title: Impact of surgical extent and sex on the hepatic metastasis of colon cancer.
abstract: OBJECTIVE
  Extensive oncological surgeries were previously suggested to increase cancer recurrence rates. We herein studied the impact of different surgical procedures and sex on colorectal cancer liver metastasis, employing several tumor inoculation approaches in BALB/c mice.
  
  
  METHODS
  Experimental hepatic metastases of the syngeneic CT26 colorectal cancer line were induced either by intra-portal inoculation or intra-splenic inoculation, employing different tumor loads. Following intra-splenic inoculation, the entire spleen or an injected hemi-spleen was removed. Additionally, the magnitude of the surgical trauma accompanying the injection procedure was manipulated.
  
  
  RESULTS
  Increasing the surgical trauma by adding laparotomy or extending the length of the surgery and hypothermia did not significantly affect the number of liver metastases or liver weight for any of the injection methods and tumor loads. The development of metastasis was significantly greater in males than in females under all conditions studied--a difference not explained by the direct effects of sex hormones on in vitro CT26 proliferation or vitality.
  
  
  CONCLUSIONS
  Concurring with less controlled clinical observations, the surgical extensiveness did not significantly affect CT26 hepatic metastasis, potentially due to a ceiling effect of the surgical trauma on the metastatic process. The sexual dimorphism observed for the CT26 metastasis should be investigated in the context of surgical stress and considering anti-CT26 immunoreactivity.
authors.affiliation: Neuroimmunology Research Unit, Department of Psychology, Tel-Aviv University, 69978, Tel-Aviv, Israel, liat.sorski@gmail.com.
authors.forename: Liat
authors.initials: L
authors.lastname: Sorski
authors.forename: Ben
authors.initials: B
authors.lastname: Levi
authors.forename: Lee
authors.initials: L
authors.lastname: Shaashua
authors.forename: Elad
authors.initials: E
authors.lastname: Neeman
authors.forename: Marganit
authors.initials: M
authors.lastname: Benish
authors.forename: Pini
authors.initials: P
authors.lastname: Matzner
authors.forename: Aviad
authors.initials: A
authors.lastname: Hoffman
authors.forename: Shamgar
authors.initials: S
authors.lastname: Ben-Eliyahu
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008807:Mice, Inbred BALB C; D019060:Minimally Invasive Surgical Procedures; D009368:Neoplasm Transplantation / Q000379:methods; D012727:Sex Characteristics