Evaluating the effectiveness and safety of immune checkpoint inhibitors in combination with radiotherapy in advanced melanoma.

This study evaluated the effectiveness and safety of immune checkpoint inhibitors (ICIs) in combination with palliative (treatment to relieve pain) radiotherapy (pRT) for the treatment of patients with advanced melanoma. The data showed that the addition of pRT to ICIs is effective and safe in these patients.

Melanoma is an aggressive type of skin cancer. It has a high tendency to spread to other parts of the body (metastasis). The standard treatment for advanced melanoma is a combination of immunotherapy, chemotherapy, surgical removal of tumors, and radiation therapy (RT).

Immunotherapy uses the body’s own immune system to fight cancer. ICIs are a type of immunotherapy used to treat a wide variety of cancers. Tumor cells try to avoid death by switching off our immune system. ICIs work by blocking the off switch of the immune system. Pembrolizumab (Keytruda) and nivolumab (Opdivo) are examples of ICIs that work by inhibiting (blocking) PD-1, an important protein in the immune system. This inhibition triggers the immune system to attack tumor cells and kills them. RT is commonly added to immune checkpoint inhibitors (ICI) when treating melanoma. RT also relieves pain in patients with cancer. However, the effectiveness and safety of ICIs in combination with pRT in advanced melanoma is still unclear.

This study analyzed 9 studies with 5817 patients with melanoma. Patients were treated with a combination of ICIs plus pRT. They were followed up for an average of 10 to 20.3 months. 

ICIs plus pRT showed significant improvements in objective response rate (ORR; partial or complete disappearance of cancer cells), complete response (CR; complete disappearance of cancer cells), and one-year local control (no amount of cancer cells left at the primary tumor site).

ICIs plus RT showed improvement in overall survival and survival without cancer worsening in some studies. No significant increases in immune-related side effects were seen with the combined treatment compared with ICIs alone.

This study concluded that the addition of pRT to ICIs is effective and safe in patients with advanced melanoma.

This study looked back in time at medical records. There were differences in study design, sample size, follow-up time, eligibility criteria, choice of ICI, RT regimen, the timing of RT in relation to immunotherapy in the studies analyzed. More studies are needed to identify optimal conditions for combination treatment.