PROGNOSTIC VALUE OF POSTTREATMENT FEDG-PET IMAGING FOLLOWING COMBINED CHEMORADIATION THERAPY IN LOCALLY ADVANCED CERVICAL CANCER

International audience; Objectives - To evaluate the performances of posttreatment FEDG-PET to predict the prognosis of patients treated with concurrent chemoradiotherapy (CT/RT) for locally advanced cervical cancer. Materials and methods - The medical records of 131 patients treated in 9 French academic institutions for IB2-IIB cervical cancer and for which a posttherapy FEDG-PET was performed were reviewed. All patients received CT/RT, possibly completed with vaginal brachytherapy (VBT) and completion surgery. Posttreatment FEDG-PET was performed within 3 months after completion of CT/RT or VBT. Incomplete metabolic response (IMR) was defined as the persistence of FEDG uptake. Results - An IMR was identified in 44 (33.6 %) cases. IMR was associated with higher risk of recurrence (aHR = 2.8; 95 %CI: 1.3-5.7; p = 0.006) and death (aHR = 4.5 ;95 %CI: 1.4-13.8; p = 0.009). Completion surgery was performed in 61 (46.9 %) patients with histologic cervical residual disease identified in 31 (50.8 %). FEDG-PET sensitivity and specificity in predicting cervical residual disease following CT/RT was 48.4 % (95 %CI: 30.8-66) and 80 % (95 %CI: 65.7-94.3), respectively. Conclusions - In patients treated with CT/RT for locally advanced cervical cancer, despite limited performances to predict cervical residual disease, posttreatment FEDG-PET is predictive of patients' prognosis and long-term outcome.