Hiện nay, các xét nghiệm gen KRAS, BRAF là những xét nghiệm thường qui được triển khai thực hiện tại các phòng thí nghiệm sinh học phân tử của các bệnh viện lớn trên cả nước như Bệnh viện Bạch Mai, Bệnh viện K, Bệnh viện Đại Học Y Hà Nội, Bệnh viện Chợ rẫy... Năm 2016, Mai Trọng Khoa và cộng sự tiến hành nghiên cứu trên 92 bệnh nhân UTĐTT, kết quả phát hiện được 34 bệnh nhân (37%) có đột biến gen KRAS, vị trí đột biến tập trung chủ yếu ở codon 12 (65,7%) [3]. Một số nghiên cứu khác với cỡ mẫu ít hơn cũng cho thấy tỷ lệ đột biến gen KRAS
khoảng 33% [1, 6]. Các nghiên cứu đánh giá về đáp ứng với thuốc còn hạn chế tuy nhiên kết quả ban đầu cho thấy thuốc kháng EGFR có góp phần vào hiệu quả điều trị trên bệnh nhân UTĐTT giai đoạn muộn. Gen NRAS và PIK3CA đã được nghiên
cứu khá nhiều trên thế giới, tuy nhiên ở Việt Nam hiện vẫn chưa có báo cáo nào liên quan.
Hiện nay có nhiều phương pháp phát hiện đột biến gen được sử dụng như giải trình tự gen, real-time PCR, PCR đặc hiệu allele... Các phương pháp này khác nhau về độ nhạy, độ đặc hiệu, số lượng đột biến có thể phát hiện… Từ năm 2014, Đơn vị Gen trị liệu (thuộc Trung tâm Y học hạt nhân và Ung bướu, Bệnh viện Bạch Mai) đã áp dụng xét nghiệm đột biến gen KRAS bằng kỹ thuật PCR đặc hiệu allele kết hợp lai đầu dò phân tử theo kit KRAS StripAssay® (hãng ViennaLab, Áo). Đây là phương pháp có độ nhạy cao, phát hiện được đột biến ngay cả khi số lượng tế bào mang đột biến dưới 1%, đã được cấp chứng chỉ tiêu chuẩn xét nghiệm châu Âu được áp dụng cho chẩn đoán bệnh (CE-IVD). Kỹ thuật này cũng được triển khai để thực hiện xét nghiệm gen BRAF và đến đầu năm 2016 gen NRAS cũng được triển khai xét nghiệm trên bệnh nhân UTĐTT để phục vụ chẩn đoán và điều trị.
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