Predictors of Immunotherapy Response in Hepatobiliary Malignancies Remain Elusive

Identifying predictive biomarkers for response to immunotherapy in patients with hepatobiliary malignancies has proven a challenge for scientists, according to a review article published in Hepatobiliary & Pancreatic Diseases International.

“Biomarkers for immune checkpoint inhibitor response of hepatobiliary malignancies remain in the exploration stage and lack compelling evidence,” wrote researchers from the Fudan University Cancer Metastasis Institute in Shanghai, China. “Currently, no single biomarker shows powerful efficiency in predicting immunotherapeutic response.”

The review included articles on the topic published through April 2022 covering tumor programmed death-ligand 1 (PD-L1) expression, tumor mutational burden, mismatch repair deficiency/high microsatellite instability, and emerging biomarkers.

Although PD-L1 expression is the most commonly studied biomarker in hepatocellular carcinoma and biliary tract cancers, results on its predictive potential are conflicting, according to the piece. Research into tumor mutational burden as a predictive biomarker is rare because it tends to be low in patients with hepatocellular carcinoma and biliary tract cancers.

In patients with biliary tract cancers, mismatch repair deficiency/high microsatellite instability appears a promising biomarker for anti-PD-1 therapy response, the review reported. Meanwhile, future avenues for predicting immunotherapy response include gut microbiota, which has shown potential in preliminary studies, and noninvasive radiomics and liquid-biopsy biomarkers.

“The predictive combination of multiple biomarkers,” researchers advised, “may be a promising direction.”

—Jolynn Tumolo

Reference

Lin ZF, Qin LX, Chen JH. Biomarkers for response to immunotherapy in hepatobiliary malignancies. Hepatobiliary Pancreat Dis Int. 2022;21(5):413-419. doi: 10.1016/j.hbpd.2022.08.002