KIT and BRAF Mutational Status in a Patient with a Synchronous Lentigo Maligna Melanoma and a Gastrointestinal Stromal Tumor

Excerpt

To the Editor: Molecular events may determine clinicopathologic types of melanoma. Aberrations affecting the KIT oncogene have been demonstrated in mucosal and acral melanomas and in melanomas on chronically sun-exposed areas.[1] Improved understanding of such genotype-phenotype correlations impacts on the development of therapies. Similarly, progress has been achieved in targeted treatment with tyrosine kinase inhibitors (for example, imatinib) of gastrointestinal stromal tumors (GISTs), in which KIT mutations occur in up to 80% of cases. To date, significant responses to imatinib have also been demonstrated in melanomas harboring KIT mutations.[2,3] We report the first case of synchronous GIST and lentigo maligna melanoma (LMM) in the same patient where oncogenic KIT may play an important role and in whom molecular genotyping was undertaken to determine whether targeted chemotherapy with imatinib might be justified. …