ABSTRACT
OBJECTIVE: To identify variables associated with a patients' ability to reproducibly hold their breath for deep-inspiration breath-hold (DIBH) radiotherapy (RT) and to develop a predictive model for DIBH eligibility. METHODS: This prospective, single-institution, IRB-approved observational study included women with left-sided breast cancer treated between January 2023 and March 2024. Patients underwent multiple breath-hold sessions over 2-3 consecutive days. DIBH waveform metrics and clinical factors were recorded and analysed. Logistic mixed modelling was used to predict DIBH eligibility, and a temporal validation cohort was used to assess model performance. RESULTS: In total, 253 patients were included, with 206 in the model development cohort and 47 in the temporal validation cohort. The final logistic mixed model identified increasing average breath-hold duration (OR, 95% CI: 0.308, 0.104-0.910. p = 0.033) and lower amplitude (OR, 95% CI: 0.737, 0.641-0.848. p < 0.001) as significant predictors of DIBH eligibility. Increasing age was associated with higher odds of being ineligible for DIBH (OR, 95% CI: 1.040, 1.001-1.081. p = 0.044). The model demonstrated good discriminative performance in the validation cohort with an AUC of 80.9% (95% CI: 73.0-88.8). CONCLUSION: The identification of variables associated with DIBH eligibility and development of a predictive model has the potential to serve as a decision-support tool. Further external validation is required before its integration into routine clinical practice.
Subject(s)
Breath Holding , Unilateral Breast Neoplasms , Humans , Female , Prospective Studies , Unilateral Breast Neoplasms/radiotherapy , Middle Aged , Aged , Adult , Breast Neoplasms/radiotherapy , Breast Neoplasms/pathology , Aged, 80 and overABSTRACT
Oligometastatic non-small cell lung cancer (OMD NSCLC) has been proposed to bridge the spectrum between non-metastatic and widely metastatic states and is perceived as an opportunity for potential cure if removed. Twelve clinical trials on local treatment have been reported, yet none are conclusive. These trials informed the development of a joint clinical practice guideline by the American & European Societies for Radiation Oncology, which endorses local treatment for OMD NSCLC. However, the heterogeneity between prognostic factors within these trials likely influenced outcomes and can only support guidance at this time. Caution against an uncritical acceptance of the guideline is discussed, as strong recommendations are offered based on expert opinion and inconclusive evidence. The guideline is also examined by a patient's caregiver, who emphasizes that uncertain evidence impedes shared decision making.