KRAS and malignant colon neoplasm: As shown in Fig. 8B and Additional file 3: Figure S3B, arterial CTCs and venous CTCs of patients with colon cancer can detect more mutated genes than tissue, and arterial CTCs can detect the mutated genes targeted with clinically available drugs (Fbxw7), while tissues can also detect the mutated genes targeted with clinically available drugs (KRAS).