Introduction/Background*Radiation field planning in patients with locally advanced cervical cancer (LACC) undergoing primary definitive chemoradiotherapy is influenced by lymph node (LN) status. LN assessment by imaging methods has several known limitations including a high false negative rate. The present study aimed to compare the accuracy of LN staging by imaging and surgical staging in LACC patients, and to evaluate their impact on radiation field planning.

Methodology A retrospective monocentric study of patients with LACC (International Federation of Gynecology and Obstetrics (FIGO 2018) stage IIA -IVA), undergoing primary definitive platinum-based chemoradiation therapy. Patients were included if LN assessment was available by both methods: surgical (paraaortic/pelvic) and imaging [Thorax/Abdomen Computed Tomography (CT) and/or pelvic Magnetic Resonance Imaging (MRI)].

Result(s)*A total of 58 patients met the inclusion criteria (table 1), 97% (n=56) had a preoperative CT and 88% (n=51) an MRI evaluation. All patients underwent surgical LN staging: 100% paraaortic, and 86% (n=50) additional pelvic lymphadenectomy. Histologically proven LN metastases after surgical LN staging were found in 76% of patients (n=44), 31% (n=18) paraaortic and 76% (n=38) pelvic. As a result of the surgical LN staging, 36% (n=21) of the patients were upstaged (n=11 to FIGO IIIC1 and n=10 to FIGO IIIC2), and 17% (n=10) had treatment modification (extended paraaortic field radiation). LN staging using CT and MRI exhibited a low negative predictive value (29% and 38%, respectively), with a higher positive predictive value (69% and 81%, respectively).

Conclusion*In this cohort of LACC patients, paraaortic LN metastases were present in one third of the cases, while CT/MRI imaging underestimated metastatic LN involvement. We thus stress the value of surgical paraaortic LN staging in cases of negative LN imaging, which may lead to treatment modification in about one fifth of patients.