Targeted immunotherapy in the treatment of melanoma lung metastasis

This study assessed the efficiency of inhaled interleukin-2 (IL-2) for the treatment of melanoma lung metastases.

Metastatic melanoma (cancer that has spread to other organs of the body) is often treated with systemic therapies (treatments that reach and affect the entire body), such as chemotherapy or injected biological agents. However, systemic treatments are often associated with severe side effects.

IL-2 belongs to a family of proteins called cytokines which control the actions of the immune system. IL-2 based drugs are often used as a form of immunotherapy, used to stimulate the body's immune system into attacking cancer cells. This study evaluated the effectiveness of inhaled IL-2 therapy in the treatment of lung metastasis, hypothesizing that this local delivery method may significantly reduce the side-effects associated with systemic therapy and possibly enhance drug efficiency.

This study included 17 melanoma patients diagnosed with lung metastasis. 13 of the patients had unresectable lung tumors (unable to undergo surgery) and received low dose IL-2 inhalations as primary treatment (the treatment group). 4 patients were able to undergo surgical resection of the lung metastasis and received low dose IL-2 inhalations as prevention of melanoma recurrence in the lungs (the prophylaxis group).

Out of the 13 patients in the treatment group, 33% achieved stable disease with treatment and 27% showed partial remission. Although none of the patients experienced complete remission, only 27% of patients showed disease progression despite treatment.

The average survival following surgery among the 4 patients in the prophylaxis group was 77.3 months. During IL-2 inhalation treatments, none of the patients showed recurrence of lung metastasis. In a single patient recurrence occurred prior to treatment, and following IL-2 inhalations stable disease for achieved for 46 months.

This study concluded that low-dose IL-2 inhalations are safe and effective in the treatment of melanoma lung metastases, and the prevention of recurrence following surgery.

This trial included only a small number of patients. Large randomized trials are needed to confirm the effectivity of inhaled IL-2.