Reem Ujaimi1, Michael Milosevic2, Anthony Fyles2, Akbar Beiki-Ardakani1, Marco Carlone1, Haiyan Jiang3, Patricia Lindsay2, Jason Xie1, Rachel Gerber1, Jennifer Croke2, Julia Skliarenko1, Wilfred Levin2, Kathy Han4. 1. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada. 2. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada. 3. Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada. 4. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada. Electronic address: kathy.han@rmp.uhn.on.ca.
Abstract
PURPOSE: The dose delivered to the most exposed 2 cm3 [Formula: see text] of the rectum and bladder is predictive of late rectal and bladder toxicity in cervix cancer patients. We investigated the predictive value of intermediate doses to the rectum and bladder for late rectal/bladder toxicity after MRI-guided brachytherapy for patients with locally advanced cervix cancer. METHODS AND MATERIALS: Toxicity was prospectively graded using Common Toxicity Criteria for Adverse Events v4.0 and retrospectively verified for women with Stage IB-IVA cervix cancer treated consecutively with MRI-guided brachytherapy between 2008 and 2013. The minimum equivalent dose in 2 Gy fractions delivered to 0.1, 1, 2, 5, and 10 cm3 of the rectum and bladder and the absolute volume of the rectum receiving 55, 60, 65, 70, and 75 Gy3 (V55-75) were collected. The association between dose-volume parameters and Grade 2+ rectal/bladder toxicity was examined using logistic regression. RESULTS: With a median followup of 44 months, cumulative incidences of Grade 2+ rectal and bladder toxicity among the 106 patients were 29% and 15% at 3 years, respectively. All the dose-volume parameters were significantly associated with late Grade 2+ rectal and bladder toxicity (p < 0.05), except for bladder [Formula: see text] . On multivariable logistic regression, both [Formula: see text] > 70 Gy3 and V55 > 11 cm3 (p < 0.05) were predictive of late Grade 2+ rectal toxicity, with improved model fitting and higher area under the curve compared with the model with [Formula: see text] > 70 Gy3 alone. CONCLUSIONS: In this study, V55 was predictive of late Grade 2+ rectal toxicity. Adding V55 to [Formula: see text] improved prediction accuracy.
PURPOSE: The dose delivered to the most exposed 2 cm3 [Formula: see text] of the rectum and bladder is predictive of late rectal and bladder toxicity in cervix cancerpatients. We investigated the predictive value of intermediate doses to the rectum and bladder for late rectal/bladder toxicity after MRI-guided brachytherapy for patients with locally advanced cervix cancer. METHODS AND MATERIALS: Toxicity was prospectively graded using Common Toxicity Criteria for Adverse Events v4.0 and retrospectively verified for women with Stage IB-IVA cervix cancer treated consecutively with MRI-guided brachytherapy between 2008 and 2013. The minimum equivalent dose in 2 Gy fractions delivered to 0.1, 1, 2, 5, and 10 cm3 of the rectum and bladder and the absolute volume of the rectum receiving 55, 60, 65, 70, and 75 Gy3 (V55-75) were collected. The association between dose-volume parameters and Grade 2+ rectal/bladder toxicity was examined using logistic regression. RESULTS: With a median followup of 44 months, cumulative incidences of Grade 2+ rectal and bladder toxicity among the 106 patients were 29% and 15% at 3 years, respectively. All the dose-volume parameters were significantly associated with late Grade 2+ rectal and bladder toxicity (p < 0.05), except for bladder [Formula: see text] . On multivariable logistic regression, both [Formula: see text] > 70 Gy3 and V55 > 11 cm3 (p < 0.05) were predictive of late Grade 2+ rectal toxicity, with improved model fitting and higher area under the curve compared with the model with [Formula: see text] > 70 Gy3 alone. CONCLUSIONS: In this study, V55 was predictive of late Grade 2+ rectal toxicity. Adding V55 to [Formula: see text] improved prediction accuracy.
Authors: Richard Pötter; Kari Tanderup; Christian Kirisits; Astrid de Leeuw; Kathrin Kirchheiner; Remi Nout; Li Tee Tan; Christine Haie-Meder; Umesh Mahantshetty; Barbara Segedin; Peter Hoskin; Kjersti Bruheim; Bhavana Rai; Fleur Huang; Erik Van Limbergen; Max Schmid; Nicole Nesvacil; Alina Sturdza; Lars Fokdal; Nina Boje Kibsgaard Jensen; Dietmar Georg; Marianne Assenholt; Yvette Seppenwoolde; Christel Nomden; Israel Fortin; Supriya Chopra; Uulke van der Heide; Tamara Rumpold; Jacob Christian Lindegaard; Ina Jürgenliemk-Schulz Journal: Clin Transl Radiat Oncol Date: 2018-01-11