IMP3 and incontinentia pigmenti: ROC analysis revealed that both IMP3 and Ki-67 could be used to discriminate sinonasal SCC cases from normal/IP cases, with IMP3 at a cut-off value of ≥9.5 with 100% and 81.5% sensitivity and specificity, respectively, and Ki-67 at a cut-off value of ≥22.5 with 100% and 62.5% sensitivity and specificity, respectively (P < 0.0001 for each) (Table 3).