Prognostic Significance of the Standardized Uptake Value of Pretherapeutic 18F-Labeled 2-Fluoro-2-Deoxyglucose Positron Emission Tomography/Computed Tomography in Patients With Locally Advanced Cervical Cancer

Objectives: To determine the prognostic significance of the pretreatment and posttreatment maximum standardized uptake value (SUVmax) of F-18-labeled 2-fluoro-2-deoxyglucose positron emission tomography (PET)/computed tomography imaging in patients with stage IB2-IVA cervical cancer. Methods: This was a retrospective review of cervical cancer patients with International Federation of Gynecology and Obstetrics stages IB2-IVA, from March 2008 to April 2014. All patients had pretreatment and posttreatment PET imaging and received primary whole pelvic radiation therapy with concurrent radiosensitizing chemotherapy, followed by intracavitary brachytherapy. Of the 58 patients who met the inclusion criteria, 31 patients (group A) showed no evidence of disease at last follow-up, and 27 patients (group B) presented with recurrence/persistence of disease. Results: The mean pretreatment SUVmax in group A was 17.65 +/- 7.82 versus 18.8 +/- 7.77 in group B (P = 0.577). The mean posttreatment SUVmax between the groups was 0.85 +/- 1.83 versus 6.05 +/- 3.01 (P < 0.001), respectively. The mean difference between pretreatment and posttreatment SUVmax was 17.73 +/- 7.50 in group A versus 13.29 +/- 7.15 in group B (P= 0.045). In group A, 80.7% of patients demonstrated no posttreatment hypermetabolic activity on PET imaging versus 11.1% in groupB. Of the patients who experienced treatment failure, the site of failure was pelvic in 25.9%, distant in 44.4%, and both pelvic and distant in 29.6%. Conclusions: No threshold was identified for the pretreatment SUVmax relative to the risk of recurrence. However, distinct correlations were found between the risk of recurrence, percent reduction in SUVmax, and the observation of residual hypermetabolic activity. This finding may help identify candidates for sequential chemotherapy.