Purpose/Objective(s) Stereotactic body radiotherapy (SBRT) in central lung tumors has been associated with higher rates of severe toxicity. We sought to evaluate toxicity and local control in a large cohort, and to identify predictive dosimetric parameters. Methods and Materials We identified patients who received SBRT for central tumors according to either of two definitions. Local failure (LF) was estimated using a competing-risks model, and multivariate analysis (MVA) was used to assess factors associated with LF. We reviewed patient toxicity, and applied Cox proportional hazard analysis and logrank tests to assess whether dose-volume metrics of normal structures correlated with pulmonary toxicity. Results One hundred twenty-five patients received SBRT for NSCLC (n=103) or metastatic (n=22) lesions using IMRT. The most common dose was 45Gy in 5 fractions. Median followup was 17.4 months. Incidence of grade ≥ 3 toxicity was 8.0%, including 5.6% pulmonary toxicity. Sixteen patients (12.8%) experienced grade ≥2 esophageal toxicity, including 50% of patients where PTV overlapped the esophagus. There were two treatment-related deaths. Among patients receiving biologically effective dose (BED) ≥ 80 Gy (n=108), 2-year LF was 21%. On MVA, gross tumor volume (GTV) was significantly associated with LF. None of the studied dose-volume metrics of the lungs, heart, proximal bronchial tree (PBT), or 2 cm expansion of the PBT (“no-fly-zone” or NFZ) correlated with grade ≥ 2 pulmonary toxicity. There was no difference in pulmonary toxicity between central tumors located inside the NFZ, and those outside the NFZ but with planning target volume (PTV) intersecting the mediastinum. Conclusion Using moderate doses, SBRT for central lung tumors achieves acceptable local control with low rates of severe toxicity. Dosimetric analysis showed no significant correlation between dose to the lungs, heart, or NFZ and severe pulmonary toxicity. Esophageal toxicity may be an underappreciated risk, particularly when PTV overlaps the esophagus.

While there has been significant progress in the development of rapid COVID-19 diagnostics, as the pandemic unfolds, new challenges have emerged, including whether these technologies can reliably detect the more infectious variants of concern and be viably deployed in non-clinical settings as “self-tests”. Multidisciplinary evaluation of the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW, a widely used rapid antigen test, included limit of detection, variant detection, test performance across different age-groups, and usability with self/caregiver-administration. While BinaxNOW detected the highly infectious variants, B.1.1.7 (Alpha) first identified in the UK, B.1.351 (Beta) first identified in South Africa, P.1 (Gamma) first identified in Brazil, B.1.617.2 (Delta) first identified in India and B.1.2, a non-VOC, test sensitivity decreased with decreasing viral loads. Moreover, BinaxNOW sensitivity trended lower when devices were performed by patients/caregivers themselves compared to trained clinical staff, despite universally high usability assessments following self/caregiver-administration among different age groups. Overall, these data indicate that while BinaxNOW accurately detects the new viral variants, as rapid COVID-19 tests enter the home, their already lower sensitivities compared to RT-PCR may decrease even more due to user error.

Introduction Patients treated with stereotactic body radiation therapy (SBRT) for early stage non-small cell lung cancer (NSCLC) are subject to locoregional and distant recurrence, as well as the formation of second primary lung cancers (SPLC). The optimal surveillance regimen for patients treated with SBRT for early-stage NSCLC remains unclear, and herein we investigated the post-treatment recurrence patterns and development of SPLC. Methods Three-hundred and sixty-six patients with pathologically proven inoperable early-stage NSCLC treated with SBRT between 2006 and 2013 were assessed. Patients underwent a CT scan of the chest every 3 months during years 1 and 2, every 6 months during years 3 and 4, and annually thereafter. Competing risks analysis was used for all time-to-event analyses. Results With a median follow up of 23 months, the 2-year cumulative incidence of local, nodal and distant failures were 12.2%, 16.1%, and 15.5%, respectively. Of patients with disease progression post-SBRT (n=108), 84% (n=91) occurred within the first two years. Five percent (n=19) of patients developed a SPLC. The median time to development of SPLC was 16.5 months (range 6.5 to 71.1 months), with 33% (n=6) of these patients developing SPLCs after two years. None of the never smokers, but 4% of former and 15% of current tobacco smokers developed a SPLC (p=0.005). Conclusion Close monitoring with routine CT scans within the first 2 years after SBRT is effective in detecting early disease progression. In contrast, the risk for developing a SPLC remains elevated beyond 2 years, particularly in former and current smokers.

Objectives Glucose metabolic activity measured by [18F]-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) has shown prognostic value in multiple malignancies, but results are often confounded by the inclusion of patients with various disease stages and undergoing various therapies. This study was designed to evaluate the prognostic value of tumor FDG uptake quantified by maximum standardized uptake value (SUVmax) in a large group of early-stage non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiotherapy (SBRT) using consistent treatment techniques. Materials and Methods 219 lesions in 211 patients treated with definitive SBRT for stage I NSCLC were analyzed after a median follow-up of 25.2 months. Cox regression was used to determine associations between SUVmax and overall survival (OS), disease-specific survival (DSS), and freedom from local recurrence (FFLR) or distant metastasis (FFDM). Results SUVmax >3.0 was associated with worse OS (p<0.001), FFLR (p=0.003) and FFDM (p=0.003). On multivariate analysis, OS was associated with SUVmax (HR 1.89, p=0.03), gross tumor volume (GTV) (HR 1.94, p=0.005) and Karnofsky performance status (KPS) (HR 0.51, p=0.008). DSS was associated only with SUVmax (HR 2.58, p=0.04). Both LR (HR 11.47, p=0.02) and DM (HR 3.75, p=0.006) were also associated with higher SUVmax. Conclusion In a large patient population, SUVmax >3.0 was associated with worse survival and a greater propensity for local recurrence and distant metastasis after SBRT for NSCLC.

PurposeBrain metastases are common in patients with limited-stage small cell lung cancer (LS-SCLC) due to the inability of most chemotherapeutics to penetrate the blood–brain barrier. Prophylactic cranial irradiation (PCI) is therefore recommended for use in patients with a good response to concurrent chemoradiotherapy. However, PCI is not always delivered; therefore, we investigated the reasons for PCI omission in patients who underwent therapy with curative intent.Methods and materialsWe retrospectively reviewed all patients with LS-SCLC who were treated with curative intent at our institution. Overall survival and cumulative incidence of brain metastasis were estimated by the Kaplan-Meier method. The Pearson χ2 test and Mann-Whitney U test were used to examine factors associated with PCI use, and prognostic factors were analyzed with Cox proportional hazards modeling.ResultsWe examined 208 patients who were treated for LS-SCLC at our institution. A total of 115 patients (55%) received PCI. The most common documented reason for PCI omission was patient refusal due to neurotoxicity concerns (38%). Physician assessment of being medically unfit (33%) and of advanced age (8%) were the second and third most common reasons, respectively. Karnofsky performance status and clinical American Joint Committee on Cancer stage but not PCI were significantly associated with overall survival. Only clinical stage remained an independent factor on multivariate analysis.ConclusionsApproximately half of patients with LS-SCLC ultimately receive PCI, generally for guideline-recommended reasons. The most common reason for PCI omission was patient concerns regarding neurotoxicity. Efforts to decrease PCI neurotoxicity, including hippocampal-sparing radiation and memantine use, may increase the use of this survival-improving intervention in eligible patients with LS-SCLC.