Wen KW, Rabinovitch PS, Wang D, et al. - The present study was carried out to assess the usefulness of DNA flow cytometry in identifying between malignant and benign intrahepatic biliary lesions. Researchers performed DNA flow cytometry on 47 formalin-fixed paraffin-embedded samples of intrahepatic cholangiocarcinoma (iCCA), 14 bile duct adenoma (BDA), and 18 BDH. They diagnosed aneuploidy in 22 iCCA (47%) but in none of the 32 BDA and BDH samples. The data also imply that most BDAs and BDHs, whether not all, are benign entities and may not represent precursor lesions to iCCAs that often harbor aneuploidy. The patients with aneuploid tumors may have a higher risk for tumor progression, especially during the first 3 years, although a larger cohort will be necessary to further determine the prognostic significance of aneuploidy in iCCA patients after resection.