ESTRO 2024 - Abstract Book

S976

Clinical - Gynaecology

ESTRO 2024

(DSS) rates of the low-, intermediate-, and high-risk groups based on pretreatment SCC-Ag levels and Δ log(SCC Ag)/Δ time were significantly different (100%, 90.6%, and 62.5%, respectively; P < 0.0001).

Conclusion:

Risk stratification using both pretreatment SCC-Ag levels and Δ log(SCC-Ag)/Δ time may predict treatment outcomes of patients with stage IIIC1 SCC.

Keywords: cervical SCC, prognosis, SCC antigen, stage IIIC1

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Digital Poster

Benefits of repeated FDG PET-CT in the treatment of advanced cervical cancer

Ewa Burchardt 1,2 , Michał Płachta 1,2 , Wojciech Burchardt 3,2

1 Greater Poland Cancer Center, Radiotherapy and Oncological Gynecology, Poznan, Poland. 2 University of Medical Science Poznan, Department of Electroradiology, Poznan, Poland. 3 Greater Poland Cancer Center, Brachytherapy Department, Poznan, Poland

Purpose/Objective:

The study aimed to analyze the results of chemotherapy (CT) followed by radiotherapy (RT) in patients with stage IIIC2 and IVB cervical cancer (CC). Moreover, the effectiveness of CT based on FDG PET-CT examinations performed before and after treatment in both groups separately and the search for predictive and prognostic factors was analyzed—the importance of RT after CT was assessed.

Material/Methods:

Eighty-one patients with CC treated in 2012-2021 were analyzed. Most patients were treated before introducing the new FIGO classification, so all were initially diagnosed with stage IVB. After retrospective reclassification, 51 patients were diagnosed with stage IIIC2 and 30 with stage IVB. All patients had their first FDG PET-CT scan performed before treatment. Then, the patients underwent CT according to the paclitaxel and cisplatin regimen. Afterward, the patients had a second FDG PET-CT scan, which allowed for a detailed assessment of the response to treatment. Patients with a partial or complete response (PR or CR) to the pelvic region were qualified for radical external beam radiotherapy for pelvis and paraaortic lymph nodes to 45-50,4 Gy with 1,8 Gy per fraction and intracavitary image-guided brachytherapy. Patients with progression (PR) or stable disease (SD) were disqualified from radical RT. The average follow-up time in the entire group was 19.2 months.

Results:

CR or PR to CT was achieved in 62(76%) patients: 41 (80%) from the IIIC2 group and 21 (70%) from the IVB group. Higher values from the first FDG PET-CT of total tumor glycolysis (TLG) p=0,03, metabolic tumor volume (MTV)