18F-fluorodeoxyglucose-positron emission tomography and pathologic tumor size in early-stage invasive cervical cancer.

Purpose: Cervical cancer tumor size determined by 18 F-fluorodeoxyglucose-positron emission tomography (FDG-PET) thresholding of the maximum standardized uptake value (SUV Max ) has been correlated with the determined tumor size by computed tomography and magnetic resonance imaging. The purpose of this study was to evaluate the relationship between preoperative FDG-PET tumor size and pathologic tumor diameter in patients with early-stage cervical cancer who were undergoing radical hysterectomy. Patients and Methods: Forty patients with early-stage cervical cancer underwent pretreatment FDG-PET/computed tomography before radical hysterectomy and lymph node dissection. Primary tumor diameter was defined on FDG-PET as the largest diameter of the 3-dimensional volumetric isocontour of the 40% threshold of the SUV Max . The FDG-PET measurements were compared with the tumor diameter and the histological diameter of the pathologic specimen using regression analysis, paired t test, and unpaired t test. Results: The FDG-PET tumor diameter measurements were correlated to the pathologic tumor diameter in the surgical specimen with a coefficient of determination ( R 2 ) of 0.951 and a correlation coefficient of 0.757 ( P Conclusion: There is a high level of correlation in the FDG-PET and the pathologic tumor measurements in the early-stage cervical cancer.