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

Cervical cancer tumor size determined by 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) thresholding of the maximum standardized uptake value (SUVMax) 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.

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 SUVMax. 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.

The FDG-PET tumor diameter measurements were correlated to the pathologic tumor diameter in the surgical specimen with a coefficient of determination (R2) of 0.951 and a correlation coefficient of 0.757 (P < 0.0001).

There is a high level of correlation in the FDG-PET and the pathologic tumor measurements in the early-stage cervical cancer.