Table 1.

Pro and cons of each imaging technique in the staging/restaging process

	Staging		Restaging
	Pro	Cons	Pro	Cons
ERUS	High accuracy and specificity for early rectal cancer (T)	Tends to overstage N	High accuracy for persistent lymph nodal involvement	Low accuracy for T restage
		Operator dependent
		Long learning curve
MRI	Ability to evaluate CRM	Low accuracy for lymph-nodes involvement	Good prediction for CRM involvement	Poor accuracy in predicting ypT0 and ypN0
	Best tool to select patients for neoadjuvant treatment
	High accuracy in advanced tumors
PET	Confirmation of M and N at distant sites	Low accuracy for T staging	Detection of progression at distant sites	Lack of standardization of the criteria used to assess the response

MRI: Magnetic resonance imaging; ERUS: Endorectal ultrasound; PET: Positron emission tomography; CRM: Circumferential margin.