18F-FDG PET/CT can predict nodal metastases but not recurrence in early stage uterine cervical cancer.

OBJECTIVES: To evaluate the role of the metabolic characteristics of cervical tumor uptake as predictors of a) lymph node (LN) metastases, b) recurrence, in the preoperative staging of early-stage cervical cancer.

METHODS: 89 patients with FIGO stage IB1 and IIA<4 cm cervical cancer were imaged with FDG-PET/CT before radical hysterectomy and pelvic lymphadenectomy. PET/CT images were analyzed and correlated to histological findings. Maximum and mean standardized uptake value (SUVmax, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG) of cervical lesions were calculated by an iterative adaptive algorithm. These parameters were correlated to the presence of: a) LN metastases, b) relapse after primary treatment.

RESULTS: Out of the 89 patients who underwent preoperative PET/CT scan for staging purpose, 16 were negative at cervical level: they were all pN0 and without recurrence during follow-up (mean 34.1±14.5 months). In 69 patients MTV and TLG were significantly higher (p=0.0006 and p=0.03) in pN1 patients in comparison to pN0 patients, while SUV values did not show significant differences between the two groups. No significant correlations were found between SUVmax, SUVmean, MTV, TLG and the evidence of relapse (mean follow-up 29.2±15.5 months).

CONCLUSIONS: In early-stage cervical cancer MTV and TLG correlate with the presence of nodal metastases, but their clinical impact on patients management has to be clarified. The absence of pathological cervical uptake could be a good prognostic factor, while SUVmax, SUVmean, MTV, TLG of the cervical uptake have not been found predictors of recurrence.