Table 3. Ability of nuclear β-catenin expression to differentiate paediatric fibromatosis from fibrosarcoma.

Proportion of tumour cells exhibiting nuclear β-catenin expression	Sensitivity	Specificity	PPV	NPV
Cut-off (25%)	85.7%	62.5%	66.6%	83.3%
Cut-off (50%)	75%	45.4%	33.3%	83.3%

PPV, positive predictive value; NPV, negative predictive value.