Dual-phase [18F]FDG PET/CT imaging in cervical carcinoma: enhanced metabolic characterization and novel prognostic...

Accurate staging and metabolic characterization of cervical cancer remains challenging despite advances in imaging. This study investigates the diagnostic utility of dual-phase [18F]FDG PET/CT in cervical carcinoma, with an emphasis on metabolic biomarkers and prognostic indicators.

A prospective study of 50 patients with histopathologically proven cervical cancer was conducted over 24 months. Patients underwent dual-phase [18F]FDG PET/CT imaging with initial whole-body acquisition at 40-60 minutes post-injection and delayed imaging at 120 minutes post-injection following intravenous furosemide administration. Standardized uptake values (SUV), lesion detection efficacy, lymph node characterization, and extra-pelvic metastatic patterns were analyzed using paired t-tests and chi-square analysis.

Mean SUV in initial images (9.074 ± 6.113) increased significantly to 12.964 ± 7.494 in delayed images (p < 0.001), representing a 42.8% increase in metabolic activity. Delayed imaging detected primary lesions in 48 cases (96%) versus 44 cases (88%) on initial imaging, demonstrating superior sensitivity (91.7%) and specificity (100%). Critically, seven patients (14%) demonstrated lymph node visualization only on delayed imaging, and 14% exhibited SUV kinetics consistent with high-grade malignancy. Parametrial involvement occurred in 66% of cases, with 81.8% demonstrating bilateral involvement. Extra-pelvic metastases including supraclavicular lymphadenopathy (10%), hepatic involvement (10%), and skeletal lesions (8%) were detected with superior specificity compared to conventional modalities. This study identified a novel metabolic phenotype: "delayed-accumulator lesions" (DAL), characterized by significant SUV escalation between initial and delayed imaging, associated with aggressive biological behavior and poor prognostic outcomes. Additionally, a mathematical model incorporating dual-phase SUV kinetics, parametrial invasion status, and bilateral lymph node involvement demonstrated superior prognostic stratification (AUC > 0.92) compared to conventional FIGO staging.

Dual-phase [18F]FDG PET/CT provides significantly enhanced metabolic characterization of cervical cancer, identifies novel biological markers predictive of treatment response, and enables metabolically guided precision treatment planning. The identification of delayed-accumulator lesions and dual-phase kinetic modeling represent paradigm shifts in cervical cancer stratification, with the potential to revolutionize treatment intensity selection and surveillance protocols.