Evaluating the impact of brain metastasis in the effectiveness of immunotherapy in patients with non-small cell lung cancer

This study evaluated the effectiveness of immune checkpoint inhibitors (ICI) versus chemotherapy in patients with non-small cell lung cancer (NSCLC) andy brain metastases (BM). The data showed that the effectiveness of ICIs was similar in patients with no BM symptoms and/or treated BMs. For patients with BMs, ICI combination therapy was associated with a greater overall survival benefit than that from ICI therapy alone.

NSCLC is the most common form of lung cancer. NSCLC is responsible for around 85% of all lung cancer diagnoses. In 20-40% of cases, NSCLC spreads from the lung to the brain. There are very few effective treatments available for NSCLC and BM.

Immunotherapy has been found to be effective in advanced NSCLC. ICI is a type of immunotherapy used to treat a wide variety of cancers. Tumor cells try to avoid death by switching off our immune system. ICI work by blocking the off switch of the immune system. Pembrolizumab (Keytruda) and nivolumab (Opdivo) are examples of ICIs that work by blocking PD-1, an important protein in the immune system. This inhibition triggers the immune system to attack tumor cells and killing them. Whether the effectiveness of immune checkpoint inhibitors (ICIs) is the same in patients with NSCLC and BM is still unknown.

This study analyzed 17 articles involving 10,358 patients with NSCLC. The patients were divided into 2 groups. Group 1 included 1199 patients with BM. Group 2 included 9159 patients without BM.

In group 1, ICI was associated with a 35% higher chance of longer survival compared to chemotherapy. In group 2, ICI was associated with a 26% higher chance of longer survival compared to chemotherapy.

In group 1, patients who were treated with ICI were 40% more likely to survive without progression or cancer worsening than those who were treated with chemotherapy. In group 2, patients who were treated with ICIs were 30% more likely to survive without progression or cancer worsening than those who were treated with chemotherapy.

ICI therapy alone or ICI combination therapy significantly improved overall survival and survival without progression or cancer worsening compared with chemotherapy both for patients with and without BM.

For patients with BMs, ICI combination therapy was associated with a 51% higher chance of longer survival compared to chemotherapy. ICI therapy alone was associated with a 19% higher chance of longer survival compared to chemotherapy.

This study concluded that the effectiveness of ICIs in metastatic NSCLC was similar in patients with no BM symptoms and/or treated BMs. For patients with BMs, ICI combination therapy was associated with a greater overall survival benefit than that from ICI therapy alone.

The chemotherapy regimens were different among studies. This study did not evaluate patients with symptoms and/or untreated BM.