Effect of PPIs (proton-pump inhibitors) on treatment efficacy in patients with hepatocellular carcinoma

Liver cancer is a serious and growing health issue. It's the sixth most common cancer worldwide and the third most deadly. The most prevalent type of liver cancer is called hepatocellular carcinoma (HCC). Unfortunately, the number of people diagnosed with HCC is expected to rise significantly, reaching 1.4 million cases per year by 2040. When the cancer has spread to other parts of the body or is affecting blood vessels, patients usually need systemic therapy, which treats the whole body rather than just the tumor.

One of the leading treatments for advanced liver cancer is a combination of two drugs: atezolizumab and bevacizumab. This treatment falls under a category known as immunotherapy. Immunotherapy helps the body fight cancer by boosting or modifying the immune system. The IMbrave150 study found that this combination of drugs is more effective in extending patient survival compared to another drug called sorafenib.

Our research aims to understand how a common type of medication, known as proton-pump inhibitors (PPIs), affects the success of immunotherapy in liver cancer patients. PPIs are often used to reduce stomach acid, but they can also change the bacteria in the gut, which might impact how well immunotherapy works.

In our study, we will focus on patients from the IMbrave150 trial who were treated with the atezolizumab-bevacizumab combination. We want to see if patients using PPIs have different survival rates compared to those who do not use PPIs. We will compare the two groups to determine if the use of PPIs affects the effectiveness of the immunotherapy.

We will use a statistical method called “inverse probability-of-treatment weighting” to ensure our results are accurate. This technique helps adjust for differences between patients who use PPIs and those who do not, minimizing any biases that could affect our findings.

This research is important because it could confirm our initial findings that PPIs might reduce the effectiveness of immunotherapy in liver cancer patients. If our hypothesis is correct, it would suggest that liver cancer patients undergoing immunotherapy should avoid using PPIs if possible. Given that PPIs are commonly prescribed without always being necessary, this could have significant implications for treatment practices.