A pulmonary vein atlas for radiotherapy planning.

BACKGROUND AND PURPOSE: Cardiac arrhythmia is a recognised potential complication of thoracic radiotherapy, but the responsible cardiac substructures for arrhythmogenesis have not been identified. Arrhythmogenic tissue is commonly located in the pulmonary veins (PVs) of cardiology patients with arrhythmia, however these structures are not currently considered organs-at-risk during radiotherapy planning. A standardised approach to their delineation was developed and evaluated. MATERIALS AND METHODS: The gross and radiological anatomy relevant to atrial fibrillation was derived from cardiology and radiology literature by a multidisciplinary team. A region of interest and contouring instructions for radiotherapy computed tomography scans were iteratively developed and subsequently evaluated. Radiation oncologists (n = 5) and radiation technologists (n = 2) contoured the PVs on the four-dimensional planning datasets of five patients with locally advanced lung cancer treated with 1.8-2.75 Gy fractions. Contours were compared to reference contours agreed by the researchers using geometric and dosimetric parameters. RESULTS: The mean dose to the PVs was 35% prescription dose. Geometric and dosimetric similarity of the observer contours with reference contours was fair, with an overall mean Dice of 0.80 ± 0.02. The right superior PV (mean DSC 0.83 ± 0.02) had better overlap than the left (mean DSC 0.80 ± 0.03), but the inferior PVs were equivalent (mean DSC of 0.78). The mean difference in mean dose was 0.79 Gy ± 0.71 (1.46% ± 1.25). CONCLUSION: A PV atlas with multidisciplinary approval led to reproducible delineation for radiotherapy planning, supporting the utility of the atlas in future clinical radiotherapy cardiotoxicity research encompassing arrhythmia endpoints.

Experience With the Routine Use of Electronic Patient-Reported Outcome Measures for Patients With Lung Cancer.

PURPOSE: The Christie NHS Foundation Trust launched their electronic patient-reported outcome measures (ePROMs) service in January 2019 in the routine clinical setting. The lung cancer questionnaires consist of 14 symptom items, adapted from the Common Terminology Criteria for Adverse Events (version 5.0) and the EuroQol EQ-5D-5L quality-of-life (QoL) tool. Patients with lung cancer are invited to complete questionnaires assessing their symptoms and QoL using an online platform. METHODS: The ePROM responses and clinical, pathologic, and treatment data for patients who completed the questionnaires between January 2019 and December 2020 were extracted from electronic medical records. The symptom and QoL scores of patients who completed baseline pretreatment ePROMs and also those who completed ePROMs pre- and postpalliative lung systemic anticancer therapy (SACT) or radical thoracic radiotherapy were evaluated. Pretreatment questionnaires were analyzed according to age, Eastern Cooperative Oncology Group performance status (ECOG PS), and Adult Comorbidity Evaluation-27 (ACE-27) comorbidity score. RESULTS: One thousand four hundred eighty patients with lung cancer were included. There were no statistically significant differences in symptoms and QoL scores between age groups. Cough (P = .006) and EQ-5D-5L mobility scores (P = .006) were significantly worse for patients with an ECOG PS of 0-1. Dyspnea (P = .035), hemoptysis (P = .023), nausea (P = .041), mobility (P = .004), and self-care (P = .0420) were significantly worse for those with higher ACE-27 scores (2-3 v 0-1). Palliative SACT was associated with a significant improvement in cough (P < .001) and hemoptysis (P = .025), but significantly negatively affected mobility (P = .013). Patients receiving radical thoracic radiotherapy reported a significant improvement in hemoptysis (P = .042) but worse pain (P = .002) and fatigue (P = .01). Other changes in symptom and QoL scores were not significant. CONCLUSION: The symptoms and QoL reported at baseline and before and after both palliative SACT and radical thoracic radiotherapy are clinically relevant and meaningful. We have demonstrated that routine implementation of ePROMs into clinical practice is feasible and can inform clinical practice and future research.

Prophylactic cranial irradiation (PCI), hippocampal avoidance (HA) whole brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS) in small cell lung cancer (SCLC): Where do we stand?

Small cell lung cancer (SCLC) is an aggressive form of lung cancer associated with an increased risk of develping brain metastases (BM), which are a significant cause of morbidity and mortality. Prophylactic cranial irradiation (PCI) was first introduced in the 1970s with the aim of reducing BM incidence and improving survival and quality of life (QoL). Prospective clinical trials and meta-analyses have demonstrated its effectiveness in reducing BM incidence and improving survival, across all stages of the disease following response to induction chemotherapy. Despite its long history, "unknowns" surrounding PCI use still exist and there are particular subgroups of patients for which its use remains controversial. PCI is known to cause neurocognitive toxicity which can have a significant impact on a patient's QoL. Strategies to minimise this, including the use of hippocampal avoidance radiotherapy techniques, neuroprotective drugs and stereotactic radiosurgery in place of whole brain radiotherapy for the treatment of BM, are under evaluation. This review offers a summary of the key PCI trials published to date and the current treatment recommendations based on available evidence. It also discusses the key questions being addressed in ongoing clinical trials and highlights others where there is currently a knowledge gap and therefore where further data are urgently required.

Stereotactic Radiation for Lung Cancer: A Practical Approach to Challenging Scenarios.

Stereotactic body radiation therapy (SBRT) is an effective and well-tolerated treatment for medically inoperable patients with early stage NSCLC. SBRT is a noninvasive treatment involving the delivery of ablative radiation doses with high precision in the course of a few treatments. Relative to conventionally fractionated radiation, SBRT achieves superior local control and survival. SBRT use has increased dramatically in the past 15 years and is currently considered the standard of care in cases of inoperable early stage NSCLC. It is being increasingly applied to more complex patient populations at higher risk of treatment-related toxicity. In these more complex patients, there is an increasing need to balance patient and treatment factors in selecting the optimal patients for SBRT. Here, we review several challenging clinical scenarios often encountered in thoracic multidisciplinary tumor boards.

Initial Clinical Experience of MR-Guided Radiotherapy for Non-Small Cell Lung Cancer.

Curative-intent radiotherapy plays an integral role in the treatment of lung cancer and therefore improving its therapeutic index is vital. MR guided radiotherapy (MRgRT) systems are the latest technological advance which may help with achieving this aim. The majority of MRgRT treatments delivered to date have been stereotactic body radiation therapy (SBRT) based and include the treatment of (ultra-) central tumors. However, there is a move to also implement MRgRT as curative-intent treatment for patients with inoperable locally advanced NSCLC. This paper presents the initial clinical experience of using the two commercially available systems to date: the ViewRay MRIdian and Elekta Unity. The challenges and potential solutions associated with MRgRT in lung cancer will also be highlighted.

Re-Irradiation of Recurrent Non-Small Cell Lung Cancer.

Locoregional recurrence occurs in 10%-30% of non-small cell lung cancer (NSCLC) after treatment with definitive (chemo)radiotherapy. Re-irradiation is the main curative-intent treatment option for these patients; however, it represents a therapeutic challenge for thoracic radiation oncologists. Re-irradiation practices are variable worldwide with lack of agreement on the optimal dose or the cumulative maximum dose acceptable for critical organs. The role of re-irradiation in NSCLC is also not clearly defined in the era of immunotherapy. In this review, we will present published and on-going re-irradiation studies for recurrent NSCLC. We will appraise available evidence for critical organ dose constraints and provide a framework for future therapeutic approaches and trials.