Predictors of cancer in patients with suspected pancreatic malignancy without a tissue diagnosis

The aim of this study was to identify predictive factors for malignancy in patients undergoing surgery for suspected pancreatic cancer without a preoperative tissue diagnosis.

Patients were identified by International Classification of Diseases Ninth Revision and current procedural terminology codes, respectively, for pancreatic cancer and pancreaticoduodenectomy at a single tertiary referral center between January 1998 and May 2004. Data were collected retrospectively by chart review. Multivariate analysis of potential predictive factors was performed.

A total of 150 patients underwent surgery for documented or suspected pancreatic malignancy; 102 did not have a preoperative tissue diagnosis of cancer. Of these, 75 had neoplastic disease at surgery. Average weight loss was greater for those with malignancy (13.5 vs. 4.8 lbs; P = .014) as was mean bilirubin (6.1 vs. 3.3 mg/dL; P = .006). In multivariate analysis, a combination of weight loss >20 lbs, bilirubin >3 mg/dL, and CA 19-9 >37 U/mL had both a specificity and positive predictive value of 100% for predicting malignancy regardless of bile duct abnormalities or mass lesions on endoscopic retrograde cholangiopancreatography or endoscopic ultrasound, respectively. The positive predictive value decreased to 89.5% when any 2 of these findings were present. The presence of a mass on CT or EUS alone had a sensitivity of 84%; however, no other single finding had a sensitivity >65%.

In patients suspected of having a pancreatic malignancy, weight loss, hyperbilirubinemia, and increased CA 19-9 level may be predictive of a final cancer diagnosis. Surgical exploration should be considered in these patients even in the absence of a preoperative tissue diagnosis.