RESPONSE OF METASTATIC ACRAL MELANOMA WITH KIT MUTATION TO IMATINIB

Clin Exp Dermatol. 2010 Jun 7. [Epub ahead of print]
Marked response to imatinib mesylate in metastatic acral lentiginous melanoma on the thumb.
Yamaguchi M, Harada K, Ando N, Kawamura T, Shibagaki N, Shimada S.

Department of Dermatology, University of Yamanashi, Yamanashi, Japan.
Abstract

Summary We report a case of melanoma that had a marked response to treatment with imatinib mesylate (IM). The patient was a 61-year-old man who presented with a small red nodule on the thumb and destruction of the nail plate. On histological examination, this lesion was diagnosed as a melanoma, and computed tomography revealed lymph-node swelling in the left axilla and nodules in both lung fields. Although the patient received intratumoral injections of interferon-beta and systemic administration of dacarbazine, both primary and metastatic lesions increased in size. Immunochemistry detected a KIT mutation, which was confirmed by DNA sequencing analysis, and patient was given IM. Within 2 weeks of starting the IM regimen, the size of the nodule on the nail plate markedly decreased, and the axillary lymph-node swelling and lung-nodule formation regressed. This case suggests that IM may be a promising treatment option for KIT mutation-positive melanoma.