We have examined the role of BRAF and NRAS mutations and reduced gene dosage at 9p in melanoma relapse. The study was carried out using formalin-fixed paraffin-embedded (FFPE) tumors because of the difficulties in accessing cryopreserved primary tumors; melanomas are generally too small to allow cryopreservation. In the study, 65% of tumors sampled yielded enough DNA for MLPA screening and 61% were successfully sequenced for BRAF/NRAS mutations.