title: Parathyroid hormone-related peptide and survival of patients with cancer and hypercalcemia.
abstract: OBJECTIVE
  Parathyroid hormone-related peptide (PTHrP) is the predominant cause of malignancy-associated hypercalcemia. However, its prognostic utility is unclear. We aimed to determine the prognostic value of serum PTHrP levels in patients who had hypercalcemia associated with malignancy.
  
  
  METHODS
  In this prospective case series, we evaluated 76 patients with a diagnosis of cancer and hypercalcemia (serum calcium level >/=10.3 mg/dL on at least two occasions). PTHrP levels >/=1 pmol/L were considered elevated. We used multivariate Cox regression analysis to identify factors associated with mortality.
  
  
  RESULTS
  Fifty patients (66%) died during follow-up. In a multivariate analysis, higher pretreatment calcium levels and elevated PTHrP levels were associated with increased mortality, with effects of PTHrP varying by age (P = 0.03). Survival was associated with pretreatment calcium levels both in patients over 65 years of age (hazard ratio [HR] per mg/dL = 1.5; 95% confidence interval [CI]: 1.2 to 1.8; P <0.001) and in patients aged 65 years or less (HR = 1.3; 95% CI: 1.1 to 1.5; P = 0.003). Adjusted for pretreatment calcium levels, elevated PTHrP levels were associated with increased mortality in patients aged </=65 years (HR = 3.8; 95% CI: 1.6 to 8.8; P = 0.002), but not in older patients (HR = 0.7; 95% CI: 0.3 to 1.9; P = 0.51).
  
  
  CONCLUSIONS
  PTHrP is a useful prognostic factor in malignancy-associated hypercalcemia, at least in patients aged </=65 years.
authors.affiliation: Department of Medicine, Royal Victoria Hospital, Montreal, Canada.
authors.forename: Ngoc Uyen
authors.initials: NU
authors.lastname: Truong
authors.forename: Michael D
authors.initials: MD
authors.lastname: deB Edwardes
authors.forename: Vasilios
authors.initials: V
authors.lastname: Papavasiliou
authors.forename: David
authors.initials: D
authors.lastname: Goltzman
authors.forename: Richard
authors.initials: R
authors.lastname: Kremer
mesh_terms: D015415:Biomarkers / Q000097:blood; D015897:Comorbidity; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000097:blood* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009369:Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D044162:Parathyroid Hormone-Related Protein; D036361:Peptide Hormones / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012016:Reference Values; D016019:Survival Analysis
chemical_list: D015415:Biomarkers; C470121:PTHLH protein, human; D044162:Parathyroid Hormone-Related Protein; D036361:Peptide Hormones