The role of pretreatment FDG-PET in treating cervical cancer patients with enlarged pelvic lymph node(s) shown on MRI: A phase 3 randomized trial with long-term follow-up

Purpose This report is the second analysis of a prospective randomized trial to investigate the impact of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) on cervical cancer patients with enlarged pelvic lymph nodes identified by magnetic resonance imaging. Methods and Materials Patients with newly diagnosed cervical cancer with enlarged pelvic lymph nodes but free of enlarged para-aortic lymph nodes (PALN) were eligible. Patients were randomized to receive either pretreatment FDG-PET (PET arm) or not (control arm). The whole pelvis was the standard irradiation field for all patients except those with FDG-avid extrapelvic findings. Results In all, 129 patients were enrolled. Pretreatment PET detected extrapelvic metastases in 7 patients. No new patient experienced treatment failure during the additional 4-year follow-up period. There were no significant differences between the PET arm and the control arm regarding overall survival, disease-free survival, and freedom from extrapelvic metastasis. In the control arm, 8 of 10 patients with PALN relapse had limited extrapelvic nodal failures; their 5-year disease-specific survival was 34.3%. By contrast, only 1 of 5 patients with PALN relapse in the PET arm experienced such limited failures; their 5-year survival rate was 0%. Conclusions Although the pretreatment detection of PALN did not translate into survival benefit, it indeed decreased the need for extended-field concurrent chemoradiation therapy.