Peter S N van Rossum1, Wei Deng2, David M Routman3, Amy Y Liu4, Cai Xu2, Yutaka Shiraishi2, Max Peters5, Kenneth W Merrell3, Christopher L Hallemeier3, Radhe Mohan4, Steven H Lin6. 1. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas; Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, Netherlands. 2. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. 3. Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota. 4. Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas. 5. Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, Netherlands. 6. Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: SHLin@mdanderson.org.
Abstract
INTRODUCTION: In patients with esophageal cancer, occurrence of severe radiation-induced lymphopenia during chemoradiation therapy has been associated with worse progression-free and overall survival. The aim of this study was to develop and validate a pretreatment clinical nomogram for the prediction of grade 4 lymphopenia. METHODS AND MATERIALS: A development set of consecutive patients who underwent chemoradiation therapy for esophageal cancer and an independent validation set of patients from another institution were identified. Grade 4 lymphopenia was defined as an absolute lymphocyte count nadir during chemoradiation therapy of <0.2 × 103/μL. Multivariable logistic regression analysis was used to create a prediction model for grade 4 lymphopenia in the development set, which was internally validated using bootstrapping and externally validated by applying the model to the validation set. The model was presented as a nomogram yielding 4 risk groups. RESULTS: Among 860 included patients, 322 (37%) experienced grade 4 lymphopenia. Higher age, larger planning target volume in interaction with lower body mass index, photon- rather than proton-based therapy, and lower baseline absolute lymphocyte count were predictive in the final model (corrected c-statistic, 0.76). External validation in 144 patients, among whom 58 (40%) had grade 4 lymphopenia, yielded a c-statistic of 0.71. Four nomogram-based risk groups yielded predicted risk rates of 10%, 24%, 43%, and 70%, respectively. CONCLUSIONS: A pretreatment clinical nomogram was developed and validated for the prediction of grade 4 radiation-induced lymphopenia during chemoradiation therapy for esophageal cancer. The nomogram can risk stratify individual patients suitable for lymphopenia-mitigating strategies or potential future therapeutic approaches to ultimately improve survival.
INTRODUCTION: In patients with esophageal cancer, occurrence of severe radiation-induced lymphopenia during chemoradiation therapy has been associated with worse progression-free and overall survival. The aim of this study was to develop and validate a pretreatment clinical nomogram for the prediction of grade 4 lymphopenia. METHODS AND MATERIALS: A development set of consecutive patients who underwent chemoradiation therapy for esophageal cancer and an independent validation set of patients from another institution were identified. Grade 4 lymphopenia was defined as an absolute lymphocyte count nadir during chemoradiation therapy of <0.2 × 103/μL. Multivariable logistic regression analysis was used to create a prediction model for grade 4 lymphopenia in the development set, which was internally validated using bootstrapping and externally validated by applying the model to the validation set. The model was presented as a nomogram yielding 4 risk groups. RESULTS: Among 860 included patients, 322 (37%) experienced grade 4 lymphopenia. Higher age, larger planning target volume in interaction with lower body mass index, photon- rather than proton-based therapy, and lower baseline absolute lymphocyte count were predictive in the final model (corrected c-statistic, 0.76). External validation in 144 patients, among whom 58 (40%) had grade 4 lymphopenia, yielded a c-statistic of 0.71. Four nomogram-based risk groups yielded predicted risk rates of 10%, 24%, 43%, and 70%, respectively. CONCLUSIONS: A pretreatment clinical nomogram was developed and validated for the prediction of grade 4 radiation-induced lymphopenia during chemoradiation therapy for esophageal cancer. The nomogram can risk stratify individual patients suitable for lymphopenia-mitigating strategies or potential future therapeutic approaches to ultimately improve survival.
Authors: Wang Jing; Yufei Liu; Hui Zhu; James Welsh; Saumil Gandhi; Melenda Jeter; Quynh Nguyen; Aileen B Chen; Michael O'Reilly; Zhongxing Liao; Joe Y Chang; Percy Lee; Steven H Lin Journal: Clin Transl Radiat Oncol Date: 2021-03-12
Authors: Saba Ebrahimi; Gino Lim; Amy Liu; Steven H Lin; Susannah G Ellsworth; Clemens Grassberger; Radhe Mohan; Wenhua Cao Journal: Int J Part Ther Date: 2021-04-07