Evaluating the effectiveness and safety of immune checkpoint inhibitors given before surgery for the treatment of resectable mucosal melanoma.

This study evaluated the effectiveness and safety of immune checkpoint inhibitors (ICIs) given before surgery for the treatment of patients with resectable mucosal melanoma. The data showed that ICIs given before surgery were effective with manageable side effects for these patients.

Melanoma is an aggressive type of skin cancer. Mucosal melanoma is a very rare cancer accounting for roughly 1% of all melanomas. It occurs in particular tissues in the body (mucosal tissue), lining the head and neck, nostrils, oral cavity, vagina, anus, gastrointestinal tract, and other areas. The main form of treatment is the surgical removal of tumors. Sometimes, patients need additional therapy before surgery to shrink the cancer so that it can be completely removed by surgery (neoadjuvant therapy). Additional therapy options can include immunotherapy or targeted therapy.

Immunotherapy uses the body’s own system to fight against cancer cells. Tumor cells try to avoid death by switching off our immune system. They bind to proteins on the surface of the immune cells such as PD-1/PD-L1 or CTLA-4. ICIs such as pembrolizumab (Keytruda), nivolumab (Opdivo), and ipilimumab (Yervoy) block these interactions and turn on the immune system to attack and kill the cancer cells. However, there are few studies evaluating the effectiveness and safety of ICIs given before surgery for the treatment of patients with resectable mucosal melanoma.

This study involved 36 patients with resectable mucosal melanoma. 78% of the patients received ICIs before surgery. The average follow-up period was 37.9 months.

The sites of the mucosal melanoma were the anus (53%), urinary/genital tracts (25%), head and neck (17%), and esophageal (6%).

The average survival without any cancer-related events was 9.2 months. After 3 years, 29% of the patients were alive and free of any cancer-related events. The average overall survival was not reached (exceeded the average follow-up period). After 3 years, 55% of the patients were alive.

Overall, 47% of the patients responded to the treatment. The complete response (complete disappearance of cancer cells) was 23%. The partial response (partial disappearance of cancer cells) was 23%.

The pathological response rate (pRR; the absence of cancer cells after surgery) was 35%. The overall survival was significantly higher for patients with a pRR. The survival rate without any cancer-related events was significantly higher for patients with objective response and for patients with a pRR.

39% of the patients experienced serious side effects such as hormonal imbalances, inflammation of the large intestine and liver, and nerve damage.

This study concluded that ICIs given before surgery were effective with manageable side effects for the treatment of patients with resectable mucosal melanoma.

This study looked back in time at medical records. The sample size was very small and only included patients treated at a single institution in the USA.