A phase III randomized trial on the addition of a contact x-ray brachytherapy boost to standard neoadjuvant chemo-radiotherapy for organ preservation in early rectal adenocarcinoma: 5 year results of the OPERA trial.
D Baron, T Pace Loscos, R Schiappa, N Barbet, E Dost, S Ben Dhia, S Soltani, L Mineur, I Martel, S Horn, C Picardi, A Stewart, E Cotte, R Coquard, G Baudin, L Evesque, A Dhadda, A Sun Myint, J P Gérard, J Doyen
{"title":"A phase III randomized trial on the addition of a contact x-ray brachytherapy boost to standard neoadjuvant chemo-radiotherapy for organ preservation in early rectal adenocarcinoma: 5 year results of the OPERA trial.","authors":"D Baron, T Pace Loscos, R Schiappa, N Barbet, E Dost, S Ben Dhia, S Soltani, L Mineur, I Martel, S Horn, C Picardi, A Stewart, E Cotte, R Coquard, G Baudin, L Evesque, A Dhadda, A Sun Myint, J P Gérard, J Doyen","doi":"10.1016/j.annonc.2024.10.827","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>The OPERA trial has shown that a contact X Ray Brachytherapy 50kV (CXB) boost with neoadjuvant chemoradiotherapy (NCRT) can increase organ preservation (OP) rate for early rectal adenocarcinoma (ADK) of low-mid rectum. We report the results after 5 years of follow-up.</p><p><strong>Patients and methods: </strong>OPERA was a multicenter, phase III trial that included operable patients (pts), with cT2-cT3b low-mid rectal ADK, tumors <5 cm, cN0 or cN1 <8 mm. All pts received external beam radiotherapy (EBRT): 45Gy in 25 fractions with concurrent capecitabine. Pts were randomly assigned (1:1) to receive a boost of EBRT in group A (9Gy/5 fractions) or a boost with CXB (90Gy/3 fractions) in group B. The primary end point was OP rate.</p><p><strong>Results: </strong>Out of 148 patients randomized, 141 were eligible. Between week 14-24, a clinical complete (or near) response was observed in 44 pts in group A (64%) vs 66 in group B (92%); p<0.001. The 3-year OP rate was 59% in group A vs 81% in group B (p=0.003). After update the median follow-up was 61.1 months [56.8-64.5]. The 5-year local regrowth was 39% in group A and 17% in group B (p=0.1). The difference in OP was still highly significant between both groups: A 56% vs B 79% (p=0.004). The difference was more significant if tumors < 3cm, with an OP rate of 93% in group B compared to 54% in group A. Of the 28 local regrowths, 3 occurred after 3 years of follow-up. Rectal bleeding (grade 1-2), which was the most prevalent toxicity during follow-up, disapeared most of the time after three years. Bowel function was not worsened by the CXB boost.</p><p><strong>Conclusion: </strong>The OPERA trial was the first trial to demonstrate that CXB dose escalation was increasing the OP rate with good bowel function at 3 years. At 5 years, these results are sustained, specially in small early-stage tumors. The occurrence of some local regrowth after 3 years necessitates close surveillance of these pts during the 5-year period.</p>","PeriodicalId":8000,"journal":{"name":"Annals of Oncology","volume":" ","pages":""},"PeriodicalIF":56.7000,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Oncology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1016/j.annonc.2024.10.827","RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ONCOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: The OPERA trial has shown that a contact X Ray Brachytherapy 50kV (CXB) boost with neoadjuvant chemoradiotherapy (NCRT) can increase organ preservation (OP) rate for early rectal adenocarcinoma (ADK) of low-mid rectum. We report the results after 5 years of follow-up.
Patients and methods: OPERA was a multicenter, phase III trial that included operable patients (pts), with cT2-cT3b low-mid rectal ADK, tumors <5 cm, cN0 or cN1 <8 mm. All pts received external beam radiotherapy (EBRT): 45Gy in 25 fractions with concurrent capecitabine. Pts were randomly assigned (1:1) to receive a boost of EBRT in group A (9Gy/5 fractions) or a boost with CXB (90Gy/3 fractions) in group B. The primary end point was OP rate.
Results: Out of 148 patients randomized, 141 were eligible. Between week 14-24, a clinical complete (or near) response was observed in 44 pts in group A (64%) vs 66 in group B (92%); p<0.001. The 3-year OP rate was 59% in group A vs 81% in group B (p=0.003). After update the median follow-up was 61.1 months [56.8-64.5]. The 5-year local regrowth was 39% in group A and 17% in group B (p=0.1). The difference in OP was still highly significant between both groups: A 56% vs B 79% (p=0.004). The difference was more significant if tumors < 3cm, with an OP rate of 93% in group B compared to 54% in group A. Of the 28 local regrowths, 3 occurred after 3 years of follow-up. Rectal bleeding (grade 1-2), which was the most prevalent toxicity during follow-up, disapeared most of the time after three years. Bowel function was not worsened by the CXB boost.
Conclusion: The OPERA trial was the first trial to demonstrate that CXB dose escalation was increasing the OP rate with good bowel function at 3 years. At 5 years, these results are sustained, specially in small early-stage tumors. The occurrence of some local regrowth after 3 years necessitates close surveillance of these pts during the 5-year period.
期刊介绍:
Annals of Oncology, the official journal of the European Society for Medical Oncology and the Japanese Society of Medical Oncology, offers rapid and efficient peer-reviewed publications on innovative cancer treatments and translational research in oncology and precision medicine.
The journal primarily focuses on areas such as systemic anticancer therapy, with a specific emphasis on molecular targeted agents and new immune therapies. We also welcome randomized trials, including negative results, as well as top-level guidelines. Additionally, we encourage submissions in emerging fields that are crucial to personalized medicine, such as molecular pathology, bioinformatics, modern statistics, and biotechnologies. Manuscripts related to radiotherapy, surgery, and pediatrics will be considered if they demonstrate a clear interaction with any of the aforementioned fields or if they present groundbreaking findings.
Our international editorial board comprises renowned experts who are leaders in their respective fields. Through Annals of Oncology, we strive to provide the most effective communication on the dynamic and ever-evolving global oncology landscape.