Watch and wait in locally advance rectal cancer: Past, present and future

Table 1 Clinical response criteria regarding findings in rectal exam, endoscopy and magnetic resonance imaging described in OPRA trial[20]

	Clinical complete response	Almost complete response	Incomplete response
Endoscopy	Plain, white scar	Irregular mucosal layer	Visible tumor
	Telangiectasia	Minimal nodules or rugosity in the mucosal layer
	Absence of ulceration
		Superficial ulceration
	Absence of nodules
		Light and persistent scar erythema
Digital rectal exam	Normal	Smooth induration or light mucosal layer alterations	Palpable nodules
MRI T2W	Dark signal in T2 without intermedial signal and no visible adenopathies	Dark signal in T2 with an intermedial signal	More intermediate-dark signal in T2
		And/or	No scar in T2
		Partial regression of the adenopathies	And/or
			No adenopathies regression
MRI DW	No visible tumor with B800-B1000 signal	Significant regression of the signal in B800-B1000	Insignificant signal regression in B800-B1000
		And/or
			And/or
			Clear low signal in ADC map
		Minimal/ residual signal in ADC map
	And/or
	Absent/low signal in ADC map
	A linear uniform signal in the tumor wall is a non-pathological sign

ADC: Apparent diffusion coefficient; MRI: Magnetic resonance imaging.

Table 2 Recommendations for follow-up for patients under a watch and wait strategy regarding OPRA trial[20]

Follow-up in mo	3-6	9-12	15-18	21-24	30	36	42	48	54	60
PE	√	√	√	√	√	√	√	√	√	√
Endoscopy	√	√	√	√	√	√	√	√	√	√
MRI	√	√	√	√	√	√	√	√	√	√
CT CAP	√	√	√	√	√	√	√	√	√	√
TM	√	√	√	√	√	√	√	√	√	√

CT CAP: Computed tomography chest, abdomen and pelvis; MRI: Magnetic resonance imaging; PE: Positron emission; TM: Tumor markers.