[Health Check] Confirming the Effectiveness of Treatment for Malignant Melanoma After First-Line Therapy Failure

The effectiveness of a drug used for patients with malignant melanoma who failed first-line treatment has been confirmed.

A research team led by Professors Kim Kyuhyun, Jung Mingyu, and Shin Sangjun from the Department of Oncology at Yonsei Cancer Hospital reported that the proportion of patients showing improvement after administering Regorafenib to c-KIT mutation melanoma patients who could not be treated surgically was 73.9%. The results of this study were published in the latest issue of the European Journal of Cancer.

The research team conducted a follow-up study on 23 patients with c-KIT mutation malignant melanoma whose disease progressed despite chemotherapy, treated at Yonsei Cancer Hospital and seven other university hospitals in Korea over approximately eight years since 2014, after administering Regorafenib.

The results were analyzed separately at 8 weeks after administration and at the end of the study (median 15.2 months). At 8 weeks, complete response, defined as the complete disappearance of the tumor, was observed in 2 patients (8.7%), and partial response, defined as a tumor size reduction of 30% or more, was observed in 5 patients (21.7%). The disease control rate, indicating the proportion of patients whose disease improved due to the drug, was 73.9%. The objective response rate, representing the proportion of patients showing more tumor reduction than initially expected during the study planning phase, was confirmed to be 30.4%.

At the end of the study, the progression-free survival period, during which patients survived without disease worsening, was on average 7.1 months, and the overall survival period was 21.5 months. Compared to existing treatments for c-KIT mutation malignant melanoma, Imatinib and Nilotinib, the progression-free survival period was more than 2.5 times longer (2.8?3.7 months and 3.3?6.0 months, respectively). The overall survival period was also superior with Regorafenib (21.5 months) compared to Imatinib (10.7?14.0 months) and Nilotinib (11.9?18.0 months).

Malignant melanoma is a fatal cancer that occurs in cells producing melanin, which protects the skin from ultraviolet rays. First-line treatment involves surgical removal of the tumor and surrounding tissue, or, in cases of inoperable locally advanced or metastatic melanoma, drugs such as immune checkpoint inhibitors are used.

Among Asians with malignant melanoma, 1 in 5 patients tests positive for the c-KIT mutation; however, this mutation is very rare in the United States and Europe, where skin cancer research is more advanced, and no standard treatment exists.

Professor Jung Mingyu stated, “c-KIT mutation melanoma occurs frequently in Asians, including Koreans, but is rare in Western countries that lead new drug clinical trials, so there is no standard treatment. Based on this study confirming the effect of Regorafenib in patients with this mutation, we will continue research to conquer melanoma treatment.”

This content was produced with the assistance of AI translation services.