Factors affecting the value of diffusion-weighted imaging for identifying breast cancer patients with pathological complete response on neoadjuvant systemic therapy: a systematic review

Insights into Imaging

Table 9 DWI parameters after NST

First author	ADC-value (× 10⁻³ mm²/s) pCR versus non-pCR^a	Reported/chosen ADC threshold for pCR (× 10⁻³ mm²/s)	ROC AUC (95% CI)	Sens (%)	Spec (%)	PPV (%)	NPV (%)
Shin [26]	1.43 (1.24, 1.69) versus 1.10 (0.93, 1.23) p = 0.003	1.19	0.80 (0.62, 0.94)	100	70
Santamaria [27]	1.812 ± 0.294 versus 1.563 ± 0.471 p = 0.011	n.r.
Hahn [67]		1.10 ± 0.54 versus 0.92 ± 0.33 p = 0.130		65.0	91.4	72.2	88.3
Liu (broad pCR-definition) [16]	Luminal A: 1.39 ± 0.07 versus 1.15 ± 0.09 p < 0.001	Luminal A: 1.35	0.864	75.0	96.6	75.0	96.6
	Luminal B: 1.41 ± 0.12 versus 1.17 ± 0.07 p < 0.001	Luminal B: 1.33	0.857	71.4	97.4	71.4	94.9
	HER2 enriched: 1.39 ± 0.07 versus 1.24 ± 0.08 p < 0.001	HER2-enriched: 1.38	0.792	62.5	95.2	83.3	87.0
	TN: 1.44 ± 0.09 versus 1.33 ± 0.06 p < 0.001	TN: 1.43	0.751	66.7	82.6	66.7	82.6
Woodhams [64]	Visual assessment^b	Visual	Visual	89	97	80	98

ADC apparent diffusion coefficient, HER2 human epidermal growth factor receptor 2, CI confidence interval, pCR pathological complete response, Sens sensitivity, Spec specificity, PPV positive predictive value, NPV negative predictive value, TN triple negative
^aMean ADC-value ± SD with the exception of Shin et al. [26]: median ADC and the interquartile range
^bResidual disease was defined positive in full-text, in the table above pCR is defined positive. PPV and NPV were calculated from extracted data of the full-text. Performance regarding visual assessment. Post-NST ADC-values could not be extracted for the whole study population