Purpose: To determine the prevalence and significance of incidental, subcentimeter hepatic lesions in patients with a new diagnosis of pancreatic cancer.
Materials and methods: This Institutional Review Board-approved retrospective study included 101 patients [45% men, median age 63 years (34-85)] treated for localized pancreatic adenocarcinoma at Brigham and Women's Hospital and Dana Farber Cancer Institute from January 1999 to December 2007. Initial staging and follow-up computed tomographic scans were reviewed to determine the frequency of liver lesions that were initially too small to characterize and later proved to be metastases. Clinical variables known to be prognostic for patients with pancreatic cancer were also recorded. Using Cox regression, we calculated adjusted hazard ratios to determine the association between presence of liver lesions and overall survival.
Results: A total of 31 patients (30.7%) had subcentimeter hepatic lesions on staging scans. Of these patients, 21 (20.7% of total, 67.7% of patients with lesions) had eventual metastases to the liver. Finally, of this group, 5 patients (5.0% of total, 16.1% of patients with lesions) eventually had a metastatic focus at the specific site of the original lesion. Liver lesions predicted the occurrence of metastatic disease to the liver compared with patients without lesions (67.7% with lesions vs 44.4% without, P = .034). The presence of subcentimeter liver lesions at diagnosis was significantly associated with reduced overall survival (hazard ratio 1.65; 95% confidence interval 1.03-2.64, P = .036).
Conclusions: Subcentimeter lesions in the liver are common in patients with a new diagnosis of pancreatic cancer. Approximately 16% of these lesions represent metastases. The presence of indeterminate liver lesions may be associated with reduced overall survival.
Copyright © 2012 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.