1240 Exploring radio-histological correlation in residual tumor after concurrent chemoradiotherapy for cervical cancer: a glimpse into the experience of the department of gynecology and obstetrics I at the Hassan II University Hospital In Fes

Introduction/Background Cervical cancer ranks fourth among global female cancers. Demonstrating superiority over radiotherapy alone, concurrent chemoradiotherapy is now the preferred treatment for locally advanced cancers, reducing rates of local and distant recurrence and improving both recurrence-free and overall survival for patients. Pelvic MRI is the preferred method for the initial evaluation of cervical cancers and is also recommended post concurrent chemoradiotherapy to assess the local response. Methodology A retrospective study was conducted at our institution between January 1st, 2021 and August 1st, 2023, to analyze the data of 96 patients who underwent concurrent chemoradiotherapy for cervical cancer, followed by a hysterectomy. The aim of our study is to assess the performance of MRI in predicting the presence of residual tumor, confirmed by histological analysis of a closure hysterectomy specimen. The diagnostic performance of MRI was assessed in terms of sensitivity, specificity, positive predictive value, and negative predictive value. Results The reference point in our study was the presence or absence of cervical tumor residue during closure surgery when performed. The sensitivity of post-concurrent chemoradiotherapy pelvic MRI to predict the existence of cervical tumor residue was about 75%, with a specificity of 51% and a sensitivity of 72%. Diagnostic performance of MRI did not show significant differences based on histological type. We identified that the size of the histological residue and its location (either cervica or, nodal) were the only factor significantly impacting the performance of pelvic MRI in predicting residue presence. The best performance was observed when the cervical histological residue size was more than 15mm. Conclusion The detection of a tumor residue on post-CCRT MRI predicts overall survival in patients with locally advanced cervical cancer. However, it does not predict recurrence. The performance of post-CCRT MRI in predicting histological tumor residue is limited and depends essentialy on the size of the residue. Disclosures All the authors have no financial disclosure or conflicts of interest with the presented material in this presentation.