Table 2.

Imaging Modalities for Locoregional Staging of Anal Cancer

Statement		Level of agreement	Remarks
Primary staging (baseline staging including overall locoregional staging, estimation of size, and evaluation of palpably large T3 and T4 tumors):
First Choice Modality
Overall	MRI	65%
T-staging	MRI	91–100%
N-staging	PET/CT or MRI	52–56% (PET/CT) vs 30% (MRI)	Similar results for HIV+ and HIV− cases
Second Choice Modality
Overall	PET/CT or CT	43% (PET/CT) vs 35% (CT)
T-staging	CT or PET/CT	52–61% (CT) vs 35–48% (PET/CT)	CT mainly preferred (61%) for T3–4 tumors
N-staging	Undecided	44–52% MRI vs 26–30% CT vs 17–21% PET/CT	Similar results for HIV+ and HIV− cases
Follow-up (restaging, final response assessment after 6–12 monthsa, suspected recurrence)
First Choice Modality	MRI	52%–60%	Except for nodal restaging after CRT (69% PET/CT)
Second Choice Modality	PET/CT	44%–48%	39%–48% indicated PET/CT as first choice
Other modalities:
- EAUS is not routinely used at the participants’ institutions (4%–34% yes; 13%–39% no; 43%–69% do not know)
- Lymphoscintigraphy is not routinely used for lymph node assessment at the participants’ institutions (0%–13% yes; 30% no; 56%–69% do not know)

Abbreviations: CT, computed tomography; EAUS, endoanal ultrasound; MRI, magnetic resonance imaging; PET, positron emission tomography

^a69% of participants indicated that response assessment after 6–12 months is routinely performed at their institution (17% were unsure)