ESTRO 2024 - Abstract Book

S1022

Clinical - Gynaecology

ESTRO 2024

A subset analysis of the two patients with PR showed that compared to the overall cohort, both patients exhibited low (below median) ΔADC S1S3 despite having low ADC at S1 and S3. They also exhibited high (above median) ΔR2* S1S3 , with high R2* at S3.

Conclusion:

LACC receiving CRT is characterised by increasing ADC and R2* across treatment, reflecting a shift from hypercellular tumour towards more necrotic and hypoxic disease. Parameters are less skewed with reduced kurtosis suggesting an increasingly homogenised volume. Features identified in patients with PR include low ADC at S1 and S3 and low ΔADC S1S3 indicating persisting hypercellularity despite CRT, with increasing hypoxia suggested by high ΔR2* S1S3 . These results suggest hypercellularity persisting through CRT indicates likely poorer response. The reduced increase in ADC in these populations indicates less conversion of hypercellular tumour into necrotic, dead tumour. An element contributing to this may be hypoxia, illustrated by an increased likelihood of poorer outcomes when R2* increases across treatment. Identifying these changes at S1 or S2 may serve as a warning for poor response, providing an opportunity to modify treatment approach during CRT or brachytherapy to mitigate this.

Keywords: functional, MRI, biomarker

References:

1. Pötter R et al. EMBRACE Collaborative Group. The EMBRACE II study: The outcome and prospect of two decades of evolution within the GEC-ESTRO GYN working group and the EMBRACE studies. Clin Transl Radiat Oncol. 2018 Jan 11;9:48-60. doi: 10.1016/j.ctro.2018.01.001. PMID: 29594251; PMCID: PMC5862686.

2. Abdul-Latif M et al. Functional Magnetic Resonance Imaging in Cervical Cancer Diagnosis and Treatment. Clinical Oncology. 2023 Sep 1;35(9):598-610.

1023

Digital Poster

Stereotactic radiotherapy and parp inhibitors in ovarian cancer: a knowledge and attitude survey

Gabriella Macchia 1 , Cynthia Aristei 2 , Maura Campitelli 3 , Simona Lucci 3 , Donatella Russo 4 , Francesco Deodato 1,5 , Donato Pezzulla 1 , Aida Di Stefano 6 , Maria Antonietta Gambacorta 3 , Antonella Savarese 7 , Sandro Pignata 8 , Gabriella Ferrandina 9 1 Responsible Research Hospital, Radiation Oncology, Campobasso, Italy. 2 S. Maria della Misericordia Hospital, Radiation Oncology Section, Perugia, Italy. 3 Fondazione Policlinico Universitario Agostino Gemelli IRCCS, UOC di Radioterapia, Dipartimento di Scienze Radiologiche, Radioterapiche ed Ematologiche, Roma, Italy. 4 Ospedale "Vito Fazzi", Radiotherapy Unit, Lecce, Italy. 5 Università Cattolica del Sacro Cuore Roma, Istituto di Radiologia, Roma, Italy. 6 Responsible Research Hospital, Medical Oncology, Campobasso, Italy. 7 RCCS-Regina Elena National Cancer Institute, Medical Oncology 1, Roma, Italy. 8 Istituto Nazionale Tumori, IRCCS-Fondazione G. Pascale, Department of Urology and Gynecology, Napoli, Italy. 9 Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Dipartimento Scienze Della Salute Della Donna, del bambino e Di Sanità Pubblica, UOC Ginecologia Oncologica, Roma, Italy