C-reactive Protein Score May Predict PD-1 Inhibitor Treatment Efficacy in Intrahepatic Cholangiocarcinoma

The C-reactive protein (CRP) score may be the most effective inflammation-based score to predict the overall survival (OS) of patients with intrahepatic cholangiocarcinoma (ICC) treated with anti-programmed cell death protein 1 (PD-1), according to a study published by Dove Medical Press. A higher score on any prognostic assessment was associated with a worse prognosis.

The CPR score was an independent predictor of OS. After anti-PD-1 treatment, the median OS for patients with ICC was 10.5 months.

“As an acute inflammatory response biomarker, serum CRP has been recognized as an indicator of progression for several cancers,” the study authors wrote. “Compared with other inflammation-based scores, the presence of a systemic inflammatory response revealed by CRP is the best tool to assess survival in ICC patients receiving PD-1 inhibitor therapy.”

ICC is a common liver malignancy with generally poor prognosis. While it is expected to increase 10 times in the next 30 years, treatment options are limited as are early diagnoses. ICC treatment is lately dependent on immune checkpoint inhibitors (ICIs), such as PD-1, which has been shown to have benefits. However, ICC affects everyone differently, which is why anti-PD1 treatment may not be a universal solution.

The objective of the study was to compare various inflammation-based scores in ICC patients who received anti-PD1 treatment to evaluate their prognostic role.

Researchers examined retrospective anonymous clinical data of 73 patients with ICC. The participants were 18 to 75 years of age; had histological ICC confirmation; a performance status score lower than 2; no other malignant tumors; and had received anti-PD1 therapy between February 2019 and 2021 at the Sun Yat-Sen University Cancer Center in China.

The efficacy of 10 inflammation-based scores was analyzed. Those included were CRP, the platelet-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio, lymphocyte-to-CRP ratio, lymphocyte-to-monocyte ratio, systemic immune inflammation index, CRP-to-albumin ratio, prognostic nutritional index, Glasgow Prognostic Score, and prognostic index.

Based on this study and previous analyses, researchers now suggest that CRP may be the most effective inflammation-based score because it is associated with tumor immunosuppression—so as a result, elevated CRP serum levels could effectively indicate a poor prognosis for ICC patients.

Although inflammation is the driver behind ICC development, the efficacy of PD-1 inhibitors is associated with inflammatory response. Consequently, the inflammation that is necessary for ICC development can also be what increases antitumor activity in liver tumors.

Limitations of the study include that it was conducted in a single-center cohort in China. Additionally, researchers remain unclear about ICC and the molecular mechanisms that cause inflammation. Many patients received combination treatments that created confounding variables, and CRP levels may be affected by unstable factors, such as inflammation.

“Prognostic indicators for the use of PD-1 inhibitors are urgently needed. Emerging evidence shows that inflammation-based scores are associated with cancer-specific survival,” the study authors wrote.

Reference

Yang, Z, Zhang, D, Fu, Y, et al. Inflammation-Based Scores Predict Responses to PD-1 Inhibitor Treatment in Intrahepatic Cholangiocarcinoma. Dove Medical Press. October 6, 2022. https://doi.org/10.2147/JIR.S385921