Background: Merkel cell carcinoma (MCC) is an aggressive KIT-positive cutaneous tumor. KIT mutations are considered to play a key role in the pathogenesis of various neoplasms, but have not been found so far in MCC. The aim of the present study was therefore to investigate the presence of KIT mutations in MCC.
Materials and methods: The entire coding region of KIT in the MCC cell line MCC-1 was sequenced. KIT exon 10 was amplified from archival paraffin-embedded MCC specimens by PCR and sequenced.
Results: Exon 10 M541L KIT sequence variation, which confers increased sensitivity to KIT ligand stem cell factor, was detected in the MCC-1 cell line. Sequencing of KIT exon 10 in six archival MCC specimens revealed the wild-type sequence.
Conclusion: The presence of the M541L KIT variation in MCC warrants further studies for its role in the pathogenesis of this tumor.