Biomarkers To Predict ICI Response in Hepatobiliary Cancers “Urgently” Needed

Although immune checkpoint inhibitors (ICIs) offer important therapeutic alternatives for the treatment of hepatobiliary malignancies, a new study indicates that “the clinical benefit provided by immunotherapy seems limited to a small subgroup of patients,” the investigators wrote in Hepatobiliary Pancreatic Disease International.

Drawing from published literature and clinical trials information, the authors noted that several potential biomarkers for response to ICI treatment in hepatobiliary cancers “remain in the exploration stage and lack compelling evidence. Tumor programmed death-ligand 1 (PD-L1) expression is the most widely studied biomarker in hepatocellular carcinoma (HCC) and biliary tract cancers (BTCs), but there are conflicting results on its predictive potential.”

Mismatch repair deficiency (dMMR)/high microsatellite instability (MSI-H) “may be a predictive biomarker of response to anti-PD-1 therapy in BTCs,” they pointed out. And emerging biomarkers involving gut microbiota demonstrate some promise as predictors in preliminary studies. Other promising candidates include radiomics and liquid-biopsy biomarkers, including circulating tumor cells, circulating tumor DNA (ctDNA), and exosomal PD-L1, which could offer fast, noninvasive monitoring of ICI response.

However, the investigators cautioned, no robust evidence yet exists to demonstrate the clinical value of the biomarkers tested to date in predicting immunotherapeutic response among patients with hepatobiliary cancers. “The identification of predictors for response to ICIs is an urgent need and major challenge. Further studies are warranted to validate the role of emerging biomarkers in predicting immunotherapeutic responses,” they concluded.

—Rebecca Mashaw

References

Lin ZF, Qin LX, Chen JH. Biomarkers for response to immunotherapy in hepatobiliary malignancies. Hepatobiliary Pancreat Dis Int. 2022;21(5):450-454.