title: High serum YKL-40 levels in patients with primary breast cancer is related to short recurrence free survival.
abstract: YKL-40 is a growth factor for connective tissue cells and stimulates migration of endothelial cells. YKL-40 is secreted by cancer cells, and elevated serum YKL-40 in patients with metastatic breast cancer and colorectal cancer is associated with a poorer prognosis as compared to patients with normal serum YKL-40. In the present study we evaluated the associations of preoperative serum YKL-40 in 271 patients with primary breast cancer in relation to relapse-free survival and overall survival. The median follow-up time was 5.9 years. There were 77 relapses and 69 patients died. The median serum YKL-40 concentration in the patients was 57 microg/l (range 22-688 microg/l) and significantly elevated (p < 0.0001) compared to serum YKL-40 in healthy females. Nineteen percent of the patients had high serum YKL-40 (i.e., >95 percentile of healthy females). Patients with high serum YKL-40 had shorter relapse-free interval (hazard ratio (HR) = 1.77, 95% confidence interval (CI): 1.06-2.95, p = 0.028) and overall survival (HR = 1.78, 95% CI: 1.04-3.05, p = 0.036) than patients with normal serum YKL-40. Serum YKL-40 was higher (p = 0.005) in lymph node positive patients as compared to lymph node negative patients. Multivariate analysis including lymph node status, estrogen receptor status, tumor size, age, menstrual status and serum YKL-40 showed that serum YKL-40 was an independent prognostic variable of relapse-free survival (HR = 1.73, 95% CI: 1.03-2.91, p = 0.039). Our results show that serum YKL-40 in patients with primary breast cancer at time of operation is only elevated in a small group of patients, but these patients have a shorter recurrence free interval. Further studies are required to determine the biological function of YKL-40 in breast cancer.
authors.affiliation: Connective Tissue Laboratory, Department of Rheumatology, H:S Hvidovre Hospital, Denmark. julia.johansen@post3.tele.dk
authors.forename: Julia S
authors.initials: JS
authors.lastname: Johansen
authors.forename: Ib J
authors.initials: IJ
authors.lastname: Christensen
authors.forename: Rikke
authors.initials: R
authors.lastname: Riisbro
authors.forename: Michael
authors.initials: M
authors.lastname: Greenall
authors.forename: Chen
authors.initials: C
authors.lastname: Han
authors.forename: Paul A
authors.initials: PA
authors.lastname: Price
authors.forename: Kenneth
authors.initials: K
authors.lastname: Smith
authors.forename: Nils
authors.initials: N
authors.lastname: Brünner
authors.forename: Adrian L
authors.initials: AL
authors.lastname: Harris
mesh_terms: D054392:Adipokines; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001324:Autoantigens / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000276:immunology* / Q000401:mortality*; D000071451:Chitinase-3-Like Protein 1; D018572:Disease-Free Survival; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D037102:Lectins; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D054392:Adipokines; D001324:Autoantigens; D014408:Biomarkers, Tumor; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D006023:Glycoproteins; D037102:Lectins