- Clinically negative lymph nodes as established by abdomino-pelvic CT, no more than 90 days prior toregistration; CT only for clinical classification of > T3- (with contrast if renal function is acceptable; a non-contrast CT is permitted if the patient is not a candidate for contrast) or magnetic resonance imaging (MRI), nodal sampling, or dissection. Patients with lymph nodes equivocal or questionable by imaging are eligible if the nodes are <1 cm in short axis.