Should immunotherapy and radiotherapy be considered as an effective treatment for non-small cell lung cancer?

This article analyzed the safety and effectiveness of an immunotherapy (IT) and radiotherapy (RT) combination to treat patients with non-small cell lung cancer (NSCLC). The authors found that combination therapy using an immunotherapy drug such as PD-1/PD-L1 inhibitors and RT may improve the outcomes of these patients.

NSCLC accounts for 85% of lung cancers found worldwide. The main form of treatment is the surgical removal of tumors plus chemotherapy or RT. NSCLC can be difficult to treat and new therapies are required. 

PD-1 and PD-L1 inhibitors target a protein called PD-L1 that plays a major role in cancerous cells by switching off the immune system. Blocking PD-L1 restores the capacity of the immune system to attack and kill cancer cells. Immunotherapies such as PD-1/PD-L1 inhibitors have shown activity in the treatment of NSCLC. However, the effectiveness of combining PD-1/PD-L1 inhibitors with RT for the treatment of NSCLC is still not clear.

The authors analyzed 20 clinical trials with 2027 patients with NSCLC. Patients were treated with either RT plus PD-1/PD-L1 inhibitors combined or with each treatment (RT or PD-1/PD-L1 inhibitors) alone.

The use of PD-1/PD-L1 inhibitors and RT combined was associated with a 77% longer 1-year and 2-year survival compared to each therapy alone in patients with advanced NSCLC. Combination therapy was also associated with a 2.09 times higher 1-year survival without cancer worsening compared to control therapies. Patients with advanced NSCLC also had a 2.47 times higher survival without cancer worsening when treatment with RT and PD-1/PD-L1 therapy at 2 years. 

Patients treated with RT and PD-1/PD-L1 inhibitors combination had 2.76 times higher odds of a treatment response compared to each treatment alone.

There was no increase to the rate of serious or mild side effects with the combination treatment compared to each treatment alone.

The authors concluded that the combination of PD-1/PD-L1 inhibitors and RT could improve the outcomes of patients with advanced NSCLC.

There were small population sizes in many of the studies analyzed. Further studies are needed.