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Stereotactic ablative radiotherapy (SABR) effectively treats early-stage lung cancer, but tumor motion poses accuracy challenges. Inspiratory breath hold is an established strategy to mitigate lung motion, but its practicality is limited, especially in patients with reduced lung capacity. Percussive ventilation breath hold (PVB) is an innovative, non-invasive respiratory technique designed to maintain breathing function with minimal chest motion, thus eliminating motion uncertainty and improving treatment safety. This pilot study marks the first attempt to apply the novel physiology of PVB to lung SABR treatments. The primary objectives include determining the success rate of administering PVB for 5 minutes in healthy volunteers (Arm 1) and evaluating the success rate of PVB-SABR in lung cancer patients (Arm 2). Secondary objectives involve examining time-related endpoints for breath hold duration and assessing dosimetric benefits of PVB. This interim analysis includes 10 healthy volunteers and 1 patient enrolled between 1/2023 - 7/2023 (IRB 63842). Any person age 18 or older who would be deemed clinically eligible to undergo lung SABR treatment qualified to participate. Patients in Arm 2 require a diagnosis of primary lung cancer or lung metastasis. PVB is administered with Percussionaire IPV-2C. Participants either underwent mock simulation with PVB (Arm 1) or PVB-SABR treatment (Arm 2). CO2 levels were monitored transcutaneously (Sentec), and adverse effects were recorded according to CTCAE v5. Arm 1, involving healthy volunteers, has been completed. 9 of 10 volunteers (90%) tolerated PVB for at least 5 minutes, with 3 of 10 (30%) maintaining a 10-minute breath hold. The average PVB duration was 7.32 minutes (range: 2.5 – 14.17 mins). CO2 levels increased significantly after 5 minutes of PVB (p = 0.002), indicating a correlation between PVB duration and CO2 levels. Minimal adverse events were documented, with dry mouth being the most notable (40%). All adverse events resolved within 24 hours. In addition, subjects demonstrated the ability to repeat multiple, sequential breath holds using the PVB technique. The first patient in Arm 2 has successfully been treated with PVB-SABR. They were able to maintain PVB for 10 minutes. There were no long-term adverse events. This interim analysis on the first study evaluating use of PVB-SABR indicates a high tolerance for PVB with minimal adverse effects. Duration of successful PVB correlated with CO2 levels. These findings underscore PVB's potential as a safe, effective approach to lung SABR motion management. Treatment arm completion is expected by mid-2024. Future dosimetric analysis may demonstrate potential target sparing benefits with use of PVB. Notably, we've acquired the Monsoon III, a new ventilator device with improved patient tolerability and gas exchange. To this end, we have included an additional 5 healthy volunteers and will utilize Monsoon III for future PVB-SABR treatments. [ABSTRACT FROM AUTHOR]

In IDH-mutant (mt) lower grade gliomas, homozygous deletion in CDKN2A/B (CDK-del) is an adverse prognostic marker. For astrocytomas, in recognition of a worse prognosis, tumors with CDK-del are upgraded to grade 4 in WHO 2021. Similarly, IDH-mt 1p/19q co-deleted oligodendrogliomas with CDK-del or chromosome 9p aberrations, where the CDKN2A/B locus resides, have a worse prognosis than their wildtype counterpart. However, given the rarity of this subtype, no consensus exists on how to classify and treat this subtype of oligodendrogliomas. In this preliminary analysis of an ongoing multi-institutional retrospective database of oligodendrogliomas, we hypothesize that CDK-del and associated chromosomal aberrations are adverse prognostic markers. This multi-institutional retrospective analysis comprises of over 5 major cancer institutes with ongoing accrual. Clinical information from molecularly confirmed oligodendrogliomas (IDH-mt 1p/19q co-del) are being collected. This includes histologic, pathologic, and molecular details, comprehensive course of treatment(s), patient outcomes, and follow-up data. For this preliminary analysis, median follow up and survival times were calculated using a reverse and regular Kaplan-Meier method, respectively. Currently, we have identified 20 patients with oligodendroglioma, 17 with CDK-del and 3 with chromosome 9p hemizygous loss. 50%, 39%, and 11% were histologic grade II, III, and IV, respectively. However, WHO grading system varied (2007, 2016, 2021), depending on time of diagnosis. Detailed treatment courses were available for 18 patients. 17 had upfront surgical resection, 65% with subtotal resection. Initial management was observation in 35%, chemotherapy alone in 12%, sequential chemoradiation in 18%, and concurrent chemoradiation in 35%. Of those treated with radiotherapy, 85% received 60 Gy. Chemotherapy regimens were PCV in 25%, TMZ in 67%, and Ivosidenib (IDH inhibitor) in 8%. Outcome data were available for all 20 patients, with a median follow-up of 95 months (IQR 21, 200) and a median survival of 71 months (IQR 46, 214). Preliminary analyses suggest CDKN2A/B homozygous deletion and associated chromosomal aberrations are adverse prognostic markers for oligodendrogliomas with a median survival approximately 40% of what is expected from historical comparisons of patients with predominantly wild-type CDK (e.g. median survival of 14.7 years in RTOG 9402). CDK-del was previously reported to be mutually exclusive with WHO grade II oligodendroglioma; this was not observed in our data. Further data collection are ongoing, with the goal of improving the classification and possibly, treatment recommendations for this subset of oligodendrogliomas (IRB 69688). [ABSTRACT FROM AUTHOR]

Zinc (Zn) efficient genotypes grow and yield well in Zn deficient environments. The objective of this study was to compare Zn efficiency and seed Zn content among nine winter wheat (Triticum aestivum L.) genotypes grown in chelator-buffered nutrient solutions containing 0 μmol Zn L-1 (-Zn treatment) or 3 μmol Zn L-1 (+Zn treatment). The Zn efficiency of the genotypes ranged from 24% to 46%. Zinc efficiency was positively correlated with shoot dry weight, shoot Zn content, but there was no significant correlation between Zn efficiency and shoot Zn concentration, seed Zn concentration, or seed Zn content. The results suggested that variation in Zn efficiency among these nine wheat genotypes is genetically inherent. Differences in Zn efficiency among these wheat genotypes, which are widely grown in northern China, indicate the potential to breed for wheat genotypes with increased tolerance to soil Zn deficiency. [ABSTRACT FROM AUTHOR]