title: The perioperative granulocyte/lymphocyte ratio is a clinically relevant marker of surgical stress in patients with colorectal cancer.
abstract: OBJECTIVE
  This study was to assess the clinical relevance of the blood granulocytes to lymphocytes (G/L) ratio as an early marker of surgical stress in patients with colorectal cancer.
  
  
  METHODS
  Thirty-three patients with colorectal cancer were prospectively to undergo laparoscopic-assisted (n=12) or open (n=21) surgical resection. Granulocyte and lymphocyte counts were used to calculate the G/L ratios in blood samples from all patients before the operation and post-operatively on days 1, 3 and 7. Additionally, serum inflammatory cytokines, interleukin (IL)-1β, IL-6, IL-8, tumour necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF) and macrophage (M)-CSF were assayed as markers of surgical stress.
  
  
  RESULTS
  Seven of 33 patients developed unexpected complications. Serum IL-6 (P<0.0001), G-CSF (P=0.0257), and M-CSF (P<0.0001) were higher on day 1 vs before the operation. Similarly, the G/L ratios were higher on days 1-3 vs before the operation (P<0.0001) and then gradually decreased together with the surgical stress levels. The G/L ratios and the numbers of granulocytes and lymphocytes in the blood showed no correlation with serum IL-1β or TNF-α. In contrast, the G/L ratios and the numbers of granulocytes in the blood showed significant correlation with IL-6 (Rs=0.710, P<0.0001, Rs=0.653, P<0.0001, respectively), with G-CSF (Rs=0.626, P<0.0001, Rs=0.578, P<0.0001), with M-CSF (Rs=0.470, P<0.0001, Rs=0.372, P<0.0001). However, the number of lymphocytes showed inverse correlation with IL-6 (Rs=-0.493, P<0.0001), G-CSF (Rs=-0.440, P<0.0001) and M-SCF (Rs=-0.443, P<0.0001).
  
  
  CONCLUSIONS
  The G/L ratio appears to be a simple and clinically relevant parameter for the assessment of perioperative stress in patients undergoing colorectal surgery.
authors.affiliation: Fourth Department of Surgery, Tokyo Medical University, Inashiki-Gun, Ibaraki 300-0395, Japan.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Tabuchi
authors.forename: Jiro
authors.initials: J
authors.lastname: Shimazaki
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Satani
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakachi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Takafumi
authors.initials: T
authors.lastname: Tabuchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000097:blood* / Q000601:surgery*; D003710:Demography; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood; D006098:Granulocytes / Q000166:cytology*; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D015850:Interleukin-6 / Q000097:blood; D007958:Leukocyte Count; D008214:Lymphocytes / Q000166:cytology*; D016173:Macrophage Colony-Stimulating Factor / Q000097:blood; D008297:Male; D008875:Middle Aged; D019990:Perioperative Care; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D015850:Interleukin-6; D016179:Granulocyte Colony-Stimulating Factor; D016173:Macrophage Colony-Stimulating Factor