Activating mutations of the BRAF gene and all three RAS genes were detected by polymerase chain reaction-direct sequencing, and RET/PTC1 rearrangements were screened by nested reverse transcription-polymerase chain reaction.     ///    "Twenty-eight cases (66.7%) of BRAF V600E mutation, three cases (7.1%) of RET/PTC1 rearrangement but no cases of RAS genes mutation were identified. "