Purpose: We previously found several individual FDG/PET-based prognostic factors for cervical cancer, specifically cervical tumor SUVmax, tumor volume, and highest level of lymph node (LN) involvement. For this study, we evaluate the combined use of these three prognostic factors assessed on pretreatment FDG-PET for predicting recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS). Patients and methods: The study included 234 cervical cancer patients, FIGO stage Ib1-IVa, treated with definitive radiation or chemoradiation therapy. All patients underwent FDG-PET or FDG-PET/CT at diagnosis, from which cervical tumor volume, SUVmax, and LN status were recorded. Using these PET-based factors, prognostic nomograms were created for RFS, DSS, and OS, and their prediction accuracies were measured using the concordance index (c-statistic). Results: Fifty-three percent of patients had FDG-avid LN on PET; the highest level of nodal involvement was pelvic in 84, para-aortic in 41, and supraclavicular in 10. The average cervix tumor SUVmax was 12.4 (range, 2.1-50.4) and PET tumor volume average was 66.4 cm3 (range, 3.0-535.7 cm 3). The median follow-up was 40.7 months for patients alive at last follow-up. PET LN status had the greatest influence on outcome. The c-statistics for the 3 nomograms were 0.741 for RFS, 0.739 for DSS, and 0.658 for OS. The PET-based nomograms performed better than FIGO stage with c-statistics of 0.605, 0.600 and 0.559 for RFS, DSS and OS, respectively. Conclusions: Pretreatment FDG-PET LN status, cervical tumor SUVmax, and tumor volume combined in a nomogram create good models for predicting cervical cancer RFS, DSS, and OS.
- Lymph node