Anorectal melanoma with a KIT-activating mutation, which is a target for tyrosine kinase inhibitor

作者：Itoh Miki; Goto Akira^*; Wakasugi Hideki; Yoshida Yutaka; Matsunaga Yasutaka; Fujii Kenichi; Suzuki Kazuya; Yonezawa Kazuhiko; Abe Takashi; Arimura Yoshiaki; Shinomura Yasuhisa

来源：International Journal of Clinical Oncology, 2011, 16(4): 428-434.

DOI：10.1007/s10147-010-0139-5

• Melanoma
• Mucosal membrane
• KIT
• Tyrosine kinase inhibitor
• Imatinib

Recent advances in our understanding of the genetic mutations associated with melanoma have led to the classification of distinct melanoma subtypes. A number of reports have consistently demonstrated that mucosal and acral melanomas more commonly harbor KIT-activating mutations than do other subtypes. Success in treating gastrointestinal stromal tumors with imatinib has led to speculation that KIT-mutated melanoma might also be effectively managed using this approach. A 78-year-old woman presented with a 4-month history of rectal bleeding. A colonoscopy revealed a black polypoid mass, 30 mm in diameter, originating near the dentate line, and a biopsy revealed malignant melanoma. Computed tomography showed multiple liver and lung metastases. A KIT mutation analysis showed the L576P mutation in exon 11. The patient did not want to undergo chemotherapy including a tyrosine-kinase inhibitor, so palliative radiotherapy for rectal symptoms was performed, but the patient died 4 months later due to disease progression. We describe the first case of anorectal melanoma with a KIT-activating mutation in Japan and summarize findings from the literature regarding the efficacy of KIT kinase inhibitors on this melanoma subtype.

• 出版日期2011-8