Role of serial multiparametric magnetic resonance imaging in prostate cancer active surveillance

Table 2 Qualitative determination of index of suspicion

Procedure step	Structure examined	Index of suspicion assessment
1	Assign region	Base	Superior most margin of prostate to the widest transverse diameter
		Midgland	Widest transverse diameter to ejaculatory ducts at verumontanum
		Apex	Inferior to midgland
2	Peripheral zone	Consider T2 features	4: Moderate low signal with mass like appearance
			3: Mild low signal with mass like appearance
			2: Mild low signal which is focal but not clearly mass like, moderate diffuse low signal
			1: Mild low signal, diffuse and/or feathered, linear low signal
			0: Normal signal
		Consider DWI features	4: Definite abnormality (high DWI and low ADC relative to background)
			3: Probable abnormality (low ADC)
			2: Possible abnormality (mild decrease ADC or increase DWI)
			1: Mottled
			0: Homogeneous ADC or low DWI
		Consider DCE features	4: Rapid early enhancement, wash out
			3: Rapid early enhancement, remaining strong and prolonged
			2: Mild early enhancement, plateau or progressive
			1: No early upstroke, progressive enhancement
			0: No enhancement
		Assign combined score
3	Central gland	Consider T2 features	4: Mass like low T2 signal with invasion into AFMS or peripheral zone/disrupted surgical capsule, irregularly or poorly marginated mass like low T2 signal without a capsule
			3: Mass like homogeneous low T2 signal with no capsule, preserved surgical capsule
			2: Diffuse heterogeneous signal with intact surgical capsule
			1: Encapsulated nodules
			0: Normal
4	Fibromuscular stroma	Assess for presence of disease
5	Extracapsular extension	Assess for presence of disease
6	Seminal vesicles	Assess for presence of disease

ADC: Apparent diffusion coefficient; DWI: Diffusion weighted imaging; DCE: Dynamic contrast-enhanced.