Standardized uptake value and metabolic tumor volume measured by ¹⁸F FDG PET/CT are sensitive biomarkers for the presence of lymph node metastasis in patients with cervical carcinoma.

UNLABELLED: The aim of this study was to evaluate whether tumor standardized uptake value (SUVmax) and metabolic tumor volume (MTV) associate with the presence of PET-positive pelvic/para-aortic lymph nodes (LN) in cervical cancer patients.

METHOD: Seventy-four patients with stage IB-IVB cervical cancer (squamous [n:66], nonsquamous [n:8]), who were referred to FDG-PET/CT department for initial staging, were enrolled in this study.

RESULTS: Patients were staged according to International Federation of Gynecology and Obstetrics [FIGO] criteria as; stage I (n:5), stage II (n:25), stage III (n:15) and stage IV (n:29). PET/CT detected 53 patients with hypermetabolic LN (average SUVmax: 7.5 ± 4.1, range: 4.1-22.8, pelvic LN: 29 patients, para-aortic LN:5 patients, pelvic and para-aortic LN:19 patients). SUVmax and MTV were significantly higher in patients with PET-positive LN compared to others (18.4 and 88.8 cm(3) vs. 13.9 and 39.9 cm(3) respectively, p = 0.007 for SUVmax, p = 0.0001 for MTV). Cut-off values in association with PET-positive LN were 15.2 for SUVmax and 35 cm(3) for MTV on ROC curve analysis. There was no correlation between SUVmax and MTV (correlation coefficient (R(2)) = 0.07). MTV differed significantly with FIGO stages (41, 98 and 107 cm(3), in stage II, III and IV respectively, p = 0.015).

CONCLUSION: Presence of PET-positive LN correlates with tumor SUVmax and MTV of cervical tumor. These findings support the use of PET/CT in the pretreatment evaluation of cervical cancer patients in order to identify cases with high risk of lymphatic involvement.