miRNA expression in FFPE tissues. (A) Unsupervised HC on miRNA profiles from FFPE specimens showed distinct clusters of DLBCL and BL. (B) The miRNA classifier obtained from cryopreserved tissues showed a similar expression pattern in FFPE tissues of BL and DLBCL. (C) A similar pattern was observed in DLBCL subgroups; however, to retain high predictive power, additional miRNAs were required in FFPE tissues.