ESTRO 2023

Session Item

Gynaecological

Session Code: 6014

Session Type: Poster (Digital)

Track: Clinical

[18F]FDG-PET predicts overall survival in patients with locally advanced cervical cancer.

Camilla Satragno, Italy

Presentation Number: PO-1412

Abstract

Abstract Title:

[18F]FDG-PET predicts overall survival in patients with locally advanced cervical cancer.

Authors:

camilla satragno¹, Angela Coco², Sofia Elizabeth Cena³, Francesco Lanfranchi⁴, Stefano Raffa⁵, Michela Marcenaro⁶, Matteo Bauckneht⁴, Gianmario Sambuceti⁷, Silvia Morbelli⁷, Salvina Barra⁶, Flavio Giannelli⁸, Liliana Belgioia²

¹University of Genoa, Department of experimental medicine (DIMES),, Genoa, Italy; ²IRCCS Policlinico San Martino, University of Genoa, Radiation Oncology Unit, Department of Health Sciences (DISSAL), Genoa, Italy; ³IRCCS Policlinico San Martino, University of Genoa, Radiation Oncology Unit, Department of Health Sciences (DISSAL) , Genoa, Italy; ⁴IRCCS Policlinico San Martino, University of Genoa, Nuclear Medicine Unit, Department of Health Sciences (DISSAL) , Genoa, Italy; ⁵IRCCS Policlinico San Martino, Nuclear Medicine Unit, Genoa, Italy; ⁶IRCCS Policlinico San Martino, Radiation Oncology Unit, Genoa, Italy; ⁷IRCCS Policlinico San Martino, University of Genoa, Nuclear Medicine Unit, Department of Health Sciences (DISSAL), Genoa, Italy; ⁸IRCCS Policlinico San Martino, Radiation Oncology Unit, Genoa, Italy

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Purpose or Objective

The aim of the present study was to evaluate the prognostic value of baseline clinical data and MRI, contrast enhanced CT (ceCT) and [18F]FDG-PET/CT measures to predict the overall survival (OS) in patients with locally advanced cervical cancer (LACC) treated with chemo-radiotherapy (CT-RT) and endouterine brachytherapy boost.

Material and Methods

We retrospectively analyzed all patients with histologically diagnosis of LACC, from 2010 to 2020 who had undergone FDG-PET and MRI at baseline, treated with radio-chemotherapy plus brachytherapy. Clinical and laboratory variables considered at baseline were age, FIGO stage, grading, HPV status, inflammation markers and RT dose.
We considered several parameters at MRI, ceCT and [18F]FDG-PET/CT.

All variables were included in the univariate and multivariate analysis.

Results

We included sixty patients, mean age was 59.2±13.1 (range 37-90).

At univariate analysis, FIGO stages III-IVA (HR 11.324, 95% CI 3.076-41.687; p<0.0001), the presence of metastatic para-aortic lymph nodes (N) at c.e.CT (HR 3. 608, 95% CI 1.090-11.941; p 0.036) and involvement of more than 10 pelvic N at MRI (HR 9.965, 95% CI 1.202-82.608; p 0.033) were significant predictors of OS. Among the [18F]FDG-PET/CT parameters, MTV of primary lesion (HR 1.022, 95% CI 1.002-1.043; p 0.033), MTV of N (HR 1.009, 95% CI 1.002-1.016; p 0. 015) and TLG (HR 1.002, 95% CI 1.000-1.003; p 0.033), and the presence of FDG-positive para-aortic N (HR 22.942, 95% CI 4.610-114.175; p<0.0001) obtained significance. Multivariate analysis confirmed only FIGO stages III-IVA and the presence of metastatic lymph nodes at [18F]FDG-PET/CT as independent predictors of OS (p 0.003 and p 0.005, respectively).

At Kaplan Meier analysis, patients grouped according to FIGO stage showed significantly different OS. Specifically, the median OS of stage III and IVA patients was 61 months (95% CI 9,998-112,002), while stage II patients had a median OS of 120 months (95% CI 120,000-120,000; p<0.0001). A similar result was obtained by grouping the sample according to the presence or absence of FDG-active para-aortic N. The former group showed a median OS of 25 months (95% CI 0.000-51.891), while patients without metastatic N at [18F]FDG-PET/CT presented a median OS of 120 months (95% CI 120.000-120.000; p<0.0001).

Combining the two parameters distinguished three classes of patients with significantly different OS (p<0.0001). The group with both predictors had a median OS of 13 months (95% CI 10,434-15,566), patients with only one of the two risk factors showed a median OS of 68 months (95% CI 68,000-68,000), and the group with neither prognosticator had a median OS of 120 months (95% CI 120,000-120,000).

When included in the multivariate model, this combined risk score was the only independent predictor of OS.

Conclusion

The present results confirm that the combination of baseline lymph node number at MRI and PET-derived N-MTV independently allow us to identify subgroups of patients with LACC with different OS.