title: Thymidine kinase 1 in serum predicts increased risk of distant or loco-regional recurrence following surgery in patients with early breast cancer.
abstract: BACKGROUND
  The prognostic value of the concentration of serum thymidine kinase 1 (S-TK1) with regard to recurrence in low risk breast cancer patients, 3 months after surgery was evaluated.
  
  
  METHODS
  The concentration of S-TK1 in serum was determined in 120 breast cancer patients at the time of surgery and in 67 patients 3 months after surgery, by anti-TK1 chicken IgY antibody, using a dot-blot immuno-assay. The S-TK1 concentration was compared with the serological activity of thymidine kinase (STK) and of carbohydrate antigen (CA 15-3).
  
  
  RESULTS
  A statistically significant trend (unadjusted) was found for recurrence (distant or loco-regional) in patients with a higher S-TK1 concentration, as compared with patients with a lower S-TK1 concentration. A multivariate analysis gave the same results. The hazard rate ratio for developing distant and/or loco-regional recurrence in patients with a higher S-TK1 concentration was about six to seven times higher than in patients with a lower S-TK1 concentration.
  
  
  CONCLUSIONS
  Our results indicate that the S-TK1 concentration is higher in patients developing distant and/or loco-regional recurrence 3 months post-surgery.
authors.affiliation: Department of Oncology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Qimin
authors.initials: Q
authors.lastname: He
authors.forename: Tommy
authors.initials: T
authors.lastname: Fornander
authors.forename: Hemming
authors.initials: H
authors.lastname: Johansson
authors.forename: Ulla
authors.initials: U
authors.lastname: Johansson
authors.forename: Guo Zhu
authors.initials: GZ
authors.lastname: Hu
authors.forename: Lars-Erik
authors.initials: LE
authors.lastname: Rutqvist
authors.forename: Sven
authors.initials: S
authors.lastname: Skog
mesh_terms: D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D005260:Female; D017273:Goserelin / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000201:enzymology* / Q000473:pathology; D011237:Predictive Value of Tests; D012307:Risk Factors; D013629:Tamoxifen / Q000008:administration & dosage / Q000627:therapeutic use; D013937:Thymidine Kinase / Q000097:blood*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D013629:Tamoxifen; D017273:Goserelin; D013937:Thymidine Kinase; C092717:thymidine kinase 1