title: Tumor dose-volume response in image-guided adaptive brachytherapy for cervical cancer: A meta-regression analysis.
abstract: Image-guided adaptive brachytherapy is a high precision technique that allows dose escalation and adaptation to tumor response. Two monocentric studies reported continuous dose-volume response relationships, however, burdened by large confidence intervals. The aim was to refine these estimations by performing a meta-regression analysis based on published series.
  
  
  
  Eligibility was limited to series reporting dosimetric parameters according to the Groupe Européen de Curiethérapie-European SocieTy for Radiation Oncology recommendations. The local control rates reported at 2-3 years were confronted to the mean D90 clinical target volume (CTV) in 2-Gy equivalent using the probit model. The impact of each series on the relationships was pondered according to the number of patients reported.
  
  
  
  An exhaustive literature search retrieved 13 series reporting on 1299 patients. D90 high-risk CTV ranged from 70.9 to 93.1 Gy. The probit model showed a significant correlation between the D90 and the probability of achieving local control (p < 0.0001). The D90 associated to a 90% probability of achieving local control was 81.4 Gy (78.3-83.8 Gy). The planning aim of 90 Gy corresponded to a 95.0% probability (92.8-96.3%). For the intermediate-risk CTV, less data were available, with 873 patients from eight institutions. Reported mean D90 intermediate-risk CTV ranged from 61.7 to 69.1 Gy. A significant dose-volume effect was observed (p = 0.009). The D90 of 60 Gy was associated to a 79.4% (60.2-86.0%) local control probability.
  
  
  
  Based on published data from a high number of patients, significant dose-volume effect relationships were confirmed and refined between the D90 of both CTV and the probability of achieving local control. Further studies based on individual data are required to develop nomograms including nondosimetric prognostic criteria.
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France; Laboratory of Molecular Radiotherapy, INSERM 1030, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France. Electronic address: renaud.mazeron@gustaveroussy.fr.
authors.forename: Renaud
authors.initials: R
authors.lastname: Mazeron
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Castelnau-Marchand
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Escande
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Eleonor
authors.initials: E
authors.lastname: Rivin Del Campo
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Maroun
authors.affiliation: Laboratory of Molecular Radiotherapy, INSERM 1030, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France; Department of Medical Physics, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Lefkopoulos
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France; Laboratory of Molecular Radiotherapy, INSERM 1030, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France; Effets Biologiques des Rayonnements, Institut de Recherche Biomédicale des Armées, Bretigny-sur-Orge, France.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Chargari
authors.affiliation: Department of Radiation Oncology, Brachytherapy Service, Gustave Roussy Cancer Campus Grand Paris, Villejuif, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Haie-Meder
mesh_terms: D001918:Brachytherapy / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D011336:Probability; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided; D012044:Regression Analysis; D016896:Treatment Outcome; D047368:Tumor Burden; D002583:Uterine Cervical Neoplasms / Q000473:pathology / Q000532:radiotherapy*
keywords: Cervix cancer; Dose–volume effect relationships; High-risk clinical target volume; Image-guided adaptive brachytherapy; Intermediate-risk clinical target volume; Meta-regression analysis; Tumor control probability