- Computed tomography (CT) or magnetic resonance imaging (MRI) or positron emission tomography (PET)-CT that includes the chest, abdomen and pelvis should be performed for initial radiological staging. This may be performed pre- or post-surgery =< 90 days prior to registration except in patients getting postoperative adjuvant chemotherapy, who will require CT, MRI or PET-CT including the chest and abdomen and pelvis no more than 30 days prior to registration; imaging performed postoperatively should show no evidence of residual disease