Whole lesion histogram analysis of apparent diffusion coefficient predicts therapy response in locally advanced rectal cancer

Table 4 Diagnostic performance of the best magnetic resonance imaging histogram derived parameters to detect responder patients

	Cutoff	Sensitivity	Specificity	PPV	NPV	Accuracy	AUC (95%CI)
∆%kurtosis	11.85%	94.4%	96.7%	94.4%	96.7%	96.0%	0.991 (0.925-1.000)
Post-nCRT kurtosis	0.78	93.3%	99.0%	90%	99.0%	96.0%	0.985 (0.957-1.000)
∆skewness	0.16	66.7%	99.0%	64.3%	99.0%	79.2%	0.885 (0.795-0.975)
Post-nCRT skewness	1.59	63.3%	99.0%	62.0%	99.0%	77.1%	0.815 (0.795-0.634)
Post-nCRT ADC10th	0.34×10-3 mm2/s	66.7%	73.3%	60.0%	79.0%	71.0%	0.681 (0.509-0.852)
∆%ADCmean	56.00%	56.0%	77.0%	56.0%	73.3%	66.7%	0.686 (0.500-0.820
∆%ADC10th	74.21%	61.1%	70.0%	55.0%	75.0%	66.7%	0.589 (0.483-0.815)
ROI ∆%ADCmean	55.00%	61.0%	69.0%	52.0%	72.0%	65.3%	0.583 (0.425-0.715)

ADC: Apparent diffusion coefficient; AUC: Area under the receiver operating characteristic curve; nCRT: Neoadjuvant chemoradiation therapy; NPV: Negative predictive value; PPV: Positive predictive value; ROI: Region of interest.