Chapter 11 – Treatment of Metastatic Melanoma Patients Bearing c-Kit Mutation Using Imatinib Mesylate

Malignant melanoma is the most frequent cause of mortality in skin cancer. Unlike Caucasian populations, mucosal and acral melanomas account for approximately 65% of all melanomas in Chinese populations. c-Kit mutations are more common in mucosal and acral melanomas, which can also be accompanied by an increase in c-Kit copy numbers. As a potent inhibitor targeting Abelson and c-Kit, imatinib plays an important role in the treatment of metastatic melanoma harboring c-Kit mutations or amplifications. It was demonstrated by several clinical trials that patients who harbored c-Kit mutations or amplifications might achieve a good disease control rate with imatinib. The results of these trials showed that imatinib may increase the progression-free survival, the overall response rate, and the overall survival in the selected patients with melanoma. Most adverse events were mild to moderate, but well controlled. These results demonstrated that imatinib is a promising agent in selected patients of melanomas with genetic alterations of c-Kit. However, more results of phase III trials are still urgently needed. Sequential treatment strategies after resistance of imatinib remain an important issue.