The standardized uptake value for F‐18 fluorodeoxyglucose is a sensitive predictive biomarker for cervical cancer treatment response and survival

Abstract

BACKGROUND. The objective of this study was to evaluate cervical tumor uptake of F-18 fluorodeoxyglucose (FDG) measured as the maximal standardized uptake value (SUV_max) by positron emission tomography (PET) and its association with treatment response and prognosis in patients with cervical cancer. METHODS. The study population consisted of 287 patients with stage IA2 through IVB cervical cancer who underwent pretreatment FDG-PET studies. SUV_max, tumor volume, and sites of lymph node metastasis were recorded. Therapy included surgery, chemoradiation, or palliation. RESULTS. The mean SUV_max was 11.4 (range, 1–50.4). The mean tumor volume by stage was 42.1 cm³ for stage I tumors (using International Federation of Gynecology and Obstetrics [FIGO] staging criteria), 63.7 cm³ for stage II tumors, 129.2 cm³ for stage III tumors, and 166.2 cm³ for stage IV tumors. There was no correlation between tumor volume and SUV_max (correlation coefficient [R²] = 0.01). No significant difference in SUV_max was observed between squamous histology (n = 247 patients) and nonsquamous histology (n = 40 patients; P = .089). Higher SUV_max was associated with an increased risk of lymph node metastasis at diagnosis (P = .0009). A Cox proportional-hazards model for death from cervical cancer was used to evaluate tumor histology, lymph node metastasis, tumor volume, and SUV_max. The results indicated that SUV_max was the only significant independent factor (P = .0027). Three prognostic groups were established using SUV_max. The overall survival rates at 5 years were 95% for an SUV_max ≤ 5.2, 70% for an SUV_max > 5.2 and ≤13.3, and 44% for an SUV_max > 13.3 (P < .0001). Increasing SUV_max was associated with persistent abnormal FDG uptake in the cervix on 3-month FDG-PET studies in 238 patients who received curative chemoradiation (P = .04). CONCLUSIONS. The SUV_max of the cervical tumor at diagnosis was a sensitive biomarker of treatment response and prognosis for patients with cervical cancer. Cancer 2007. © 2007 American Cancer Society.