Primary sclerosing cholangitis (PSC) is a chronic liver disorder, which can lead to cholestasis, liver injury, and fibrosis. Cholangiocarcinoma (CCA) may develop in five to ten percent of patients with PSC from a background of premalignant biliary tissue (field defect) including dysplasia. Early detection of CCA is important to increase a patient's chance of survival free of CCA recurrence.
Polysomy detected by fluorescence in situ hybridization (FISH) is associated with CCA in patients with PSC. However, a subset of PSC patients with polysomy do not manifest CCA even after long-term follow-up. It is unknown if patients with chromosomal gains detected by FISH in multiple areas of the biliary tree, or multifocal polysomy (MFP), are more likely to be diagnosed with CCA than patients with unifocal polysomy (UFP).
Mayo Clinic researchers, first author John Eaton, M.D., conducted a study published in the American Journal of Gastroenterology, to determine whether patients with MFP are more likely to manifest CCA compared with patients with other chromosomal abnormalities including UFP and other FISH subtypes.
Upon review of 371 PSC patients without a mass lesion who underwent FISH testing at Mayo Clinic, patients with MFP in comparison to those with UFP, were more likely to have weight loss, suspicious cytology, and develop serial polysomy. MFP was associated with CCA, and was the strongest predictor of cancer diagnosis. Suspicious cytology and UFP were also predictive of CCA.
Based on these results, compared with other FISH subtypes, MFP is the strongest predictor of CCA. However, patients with UFP and suspicious cytology (regardless of FISH status) are also at an increased risk for CCA.
Additional Mayo Clinic authors include: Emily Barr Fritcher C.T. (ASCP), Gregory Gores, M.D., Elizabeth Atkinson, M.S., James Tabibian, M.D., Mark Topazian, M.D., Andrea Gossard, R.N., CNP, Kevin Halling, M.D., Ph.D., Benjamin Kipp, Ph.D., and Konstantinos Lazaridis, M.D.