F-18 fluorodeoxyglucose uptake in primary cervical cancer as an indicator of prognosis after radiation therapy

Abstract

Purpose.We evaluated the prognostic significance of tumor metabolic activity on pretreatment positron emission tomography using the glucose analog F-18 fluorodeoxyglucose (FDG-PET) in patients with carcinoma of the cervix undergoing radiotherapy with or without concurrent chemotherapy. Methods.We studied 96 consecutive patients who underwent FDG-PET prior to initiation of radiotherapy with or without concurrent chemotherapy for carcinoma of the cervix. Pretreatment FDG uptake of the primary tumor was assessed with the semiquantitative standardized uptake value (SUV) and correlated with disease-free and overall survival. Survival was estimated by the Kaplan–Meier method. Univariate and multivariate analyses were performed with the logistic likelihood ratio test and the Cox proportional hazards model, respectively. Results.Five-year disease-free survivals in patients with maximal SUV <10.2 and ≥10.2 were 71% and 52% (P = 0.0289) respectively, while overall survivals were 72% and 69% (P = 0.4), respectively. On multivariate analysis, lymph node metastasis on FDG-PET was found to be predictive of disease-free survival (P < 0.0001). Both the SUV for FDG and FIGO Stage I disease were found to be marginally predictive of disease-free survival (P = 0.055 and P = 0.058, respectively). Conclusions.FDG uptake within primary cervical cancer, as measured by SUV, is predictive of disease-free survival in patients undergoing radiotherapy for cervical cancer. High FDG uptake may be useful in identifying patients who may require more aggressive initial therapy.