title: Predictors of malignancy in pancreatic head mass: a prospective study.
abstract: BACKGROUND
  The objective of the study was to identify the predictive factors for malignancy in pancreatic head mass as a primary outcome and assess the value of CA 19-9 as a diagnostic tool for malignancy as a secondary outcome.
  
  
  METHODS
  A prospective study of patients presented with pancreatic head mass was conducted in a tertiary care referral hospital, Manipal, India from May 2006 to November 2008. The study population was divided into malignant and benign groups based on the final histopathology report. A univariate and multivariate analysis of potential predictive factors for malignancy were conducted.
  
  
  RESULTS
  A total of 102 patients with pancreatic head mass were included in the study after fulfilling the inclusion/exclusion criteria. 78 were malignant and 24 were benign. There was significant weight loss (p<0.001) and high mean bilirubin levels (p=0.002) in the malignant group. Mean CA 19-9 was significantly higher in the malignant group (290.7 vs. 30.3 U/ml; p<0.001). Sensitivity and specificity of CA 19-9 for detecting malignancy in pancreatic head mass at a cut off of 35 U/ml was 86% and 79% respectively. CA 19-9 positivity rate was higher with increasing cut off values of 100, 200 and 300 U/ml but such high levels occurred in fewer patients. All the non-jaundiced patients (100%) with raised CA 19-9 levels were found to be malignant compared to 86% malignancy in jaundiced patients. In multivariate analysis, a combination of weight loss>10% of body weight and bilirubin>3 mg/dl and CA 19-9>35 U/ml had specificity and positive predictive value of 100% for predicting malignancy in pancreatic head mass.
  
  
  CONCLUSIONS
  The presence of weight loss and jaundice and raised CA 19-9 levels together in a patient with pancreatic head mass can be predictive of malignancy. A very high CA 19-9 level can be an indicator of malignancy in a pancreatic head mass. A raised CA 19-9 level may be more predictive of malignancy in non-jaundiced patients than in jaundiced patients.
authors.forename: Arjun
authors.initials: A
authors.lastname: Sivaraman
authors.affiliation: Department of Surgery , Kasturba Medical College, Manipal, Karnataka, India.
authors.forename: Arjun
authors.initials: A
authors.lastname: Sivarman
authors.forename: Ashok
authors.initials: A
authors.lastname: Muthukrishnan
authors.forename: Nagendra
authors.initials: N
authors.lastname: Boopathy Senguttvan
authors.forename: Suraj
authors.initials: S
authors.lastname: Anil Suchak
authors.forename: Umashankkar
authors.initials: U
authors.lastname: Kannan
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood*; D006801:Humans; D007194:India; D015999:Multivariate Analysis; D010190:Pancreatic Neoplasms / Q000097:blood / Q000175:diagnosis*; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen