FN1 and colorectal carcinoma: The 35 fresh-frozen and eight FFPE CRC cases with detectable Fn DNA were classified using the median cut point amount (fresh-frozen median = 4.5 × 10−6, FFPE median = 6.0 × 10−6) into two groups according to the level of Fn DNA: high (above median) or low (below median) (Supplementary Tables 3, 4).