Proton therapy for high-risk prostate cancer: Results from the Proton Collaborative Group PCG 001-09 prospective registry trial.

BACKGROUND: Data for proton therapy in high-risk prostate cancer (HRPC) are limited. Using the Proton Collaborative Group prospective registry, we evaluated outcomes for HRPC patients treated with proton therapy. METHODS: A totsl of 605 men with localized HRPC treated with proton therapy from 8/2009 to 3/2019 at nine institutions were selected. Outcomes examined included freedom from progression (FFP), metastasis free survival (MFS), overall survival (OS), and toxicity. Multivariable cox/binomial regression models were used to assess predictors of FFP and toxicity. RESULTS: Median age was 71 years. Gleason grade groups 4 (49.4%) and 5 (31.7%) were most common, as were clinical stage T1c (46.1%) and cT2 (41.3%). The median pretreatment prostate specific antigen (PSA) was 9.18 and median International Prostate Symptom Score (IPSS) was 6. Androgen deprivation therapy was given in 63.6%. Median dose was 79.2 GyE in 44 fractions. Pelvic lymph nodes were treated in 58.2% of cases. Pencil beam scanning was used in 54.5%, uniform scanning in 38.8%, and a rectal spacer in 14.2%. At a median followup of 22 months, the 3- and 5-year FFP were 90.7% and 81.4%, respectively. Five-year MFS and OS were 92.8% and 95.9%, respectively. Independent correlates of FFP included Gleason ≥8, PSA > 10, and cT2 (all p < 0.05). No grade 4 or 5 adverse events were reported. There were 23 (5%) grade 2 and 0 grade 3 gastrointestinal events. Prevalence of late grade 3, late grade 2, acute grade 3, and acute grade 2 genitourinary toxicity was 1.7%, 5.8%, 0%, and 21.8%, respectively. Prevalence of grade 2 and 3 erectile dysfunction at 2 years was 48.4% and 8.4%, respectively. CONCLUSIONS: In the largest series published to date, our results suggest early outcomes using proton therapy for HRPC are encouraging for both safety and efficacy. Further evaluation is needed to determine if an advantage exists to use protons over other radiation techniques in this population.

A Preparative Method for the Isolation of Calponin from Molluscan Catch Muscle.

We describe the development of a preparative method to isolate molluscan catch muscle, calponin. This method is based on the ability of calponin to interact with actin in a temperature-dependent manner. After extracting thin filaments, as previously described, the extract was ultracentrifuged at 2 °C. While other surface proteins of thin filaments co-precipitated with actin, calponin, along with some minor contaminants, remained in the supernatant. Calponin was purified through cation-exchange chromatography. The yield of pure protein was four-fold higher than that achieved through high-temperature extraction. To evaluate functionally isolated proteins, we determined the effect of calponin on Mg2+-ATPase activity of hybrid and non-hybrid actomyosin. The degree of ATPase inhibition was consistent with previously published data but strongly dependent on the environmental conditions and source of actin and myosin used. Furthermore, at low concentrations, calponin could induce the ATPase activity of hybrid actomyosin. This result was consistent with data indicating that calponin can modulate actin conformation to increase the relative content of "switched on" actin monomers in thin filaments. We assume that calponin obtained by the isolation method proposed herein is a fully functional protein that can both inhibit and induce the ATPase activity.

Geospatial Disparities in Access to Proton Therapy in the Continental United States.

Proton therapy (PT) is an important component of therapy for select cancers, but no formal study of geospatial access to PT has been conducted to date. Population data for 320.7 million people in 32,644 zip codes were analyzed. Median travel time was 1.61 (IQR 0.67-3.36) hours for children and 1.64 (IQR 0.69-3.33) hours for adults. Significant variation in travel time to nearest PT center was observed between states. The West has a longer median travel time of 3.51 (IQR 1.15-7.13) hours when compared to the Midwest (1.70, IQR 0.79-2.69), South (1.60, IQR 0.61-3.12) and Northeast (1.04, IQR 0.57-2.01).

Low-dose-rate brachytherapy for prostate cancer: outcomes at >10 years of follow-up.

OBJECTIVE: To examine biochemical control, survival, and late morbidity with definitive low-dose-rate brachytherapy (LDR-BT) for patients with prostate cancer surviving for >10 years after treatment. PATIENTS AND METHODS: We identified 757 men with localised prostate cancer who underwent definitive LDR-BT in the period 1990-2006 and were followed for >10 years at our institution. Biochemical failure-free survival (BFFS), distant metastases-free survival (DMFS), prostate cancer-specific survival (PCSS), and overall survival (OS) were selected as study endpoints. Survival was examined using the log-rank test, Kaplan-Meier method, and Cox regression modelling. Urinary, quality of life (QoL), and potency scores at baseline and last follow-up were recorded. RESULTS: The median follow-up was 12.5 years (range, 10.1-21.8 years). At the time of analysis, 88.6% of patients were alive, 1.5% died from prostate cancer and 13.9% developed biochemical failure, with 82% of failures occurring in the first decade of follow-up. Overall, 2.3% developed distant metastases. On multivariate analyses, stage T3a-T3b, prostate-specific antigen level of >20 ng/mL, intermediate- and high-risk disease predicted worse BFFS; whereas age >70 years at diagnosis and stage T3a-T3b predicted worse OS. A total biologically effective dose of ≥150 Gy and androgen-deprivation therapy were associated with improved BFFS, but not OS. The overall 17-year rates for BFFS, DMFS, PCSS, and OS were 79, 97, 97, and 72%, respectively. Respective 17-year BFFS rates for low-, intermediate- and high-risk patients were 86, 80, and 65% (P < 0.001), whereas OS rates for the same groups were 82, 73, and 60%, respectively (P = 0.09). Amongst those patients who were potent at baseline, 25% remained potent at the last follow-up. Urinary function and QoL were mainly unaffected. CONCLUSIONS: LDR-BT yields excellent survival rates, with a 17-year PCSS rate of 97%. In all, 18% of patients with biochemical relapse failed at >10 years after implantation, which justifies their continued follow-up.

Troponin-like regulation in muscle thin filaments of the mussel Crenomytilus grayanus (Bivalvia: Mytiloida).

Muscles of bivalve molluscs have double calcium regulation--myosin-linked and actin-linked. While the mechanism of myosin-linked regulation is sufficiently studied, there is still no consensus on the mechanism of actin-linked regulation. Earlier we showed a high degree of Ca2+-sensitivity of thin filaments from the adductor muscle of the mussel Crenomytilus grayanus (Mytiloida). In order to elucidate the nature of this regulation, we isolated the fraction of minor proteins from the mussel thin filaments, which confers Ca2+-sensitivity to reconstituted actomyosin-tropomyosin. Proteins of this fraction, ABP-19, ABP-20, and ABP-28, were chromatographically purified and identified. According to the results of mass spectrometry and Western blot analysis, as well as by their functional properties, these mussel actin-binding proteins appeared to correspond to the troponin components from the skeletal muscles of vertebrates (TnC, TnI and TnT). The reconstituted mussel troponin complex confers to actomyosin-tropomyosin more than 80% Ca2+-sensitivity. The in vivo molar ratio of actin/tropomyosin/troponin was calculated to be 7:1:0.5, i.e., the content of troponin in mussel thin filaments is two times lower than in thin filaments of skeletal muscles of vertebrates. These data demonstrate that troponin-like regulation found in the catch muscle of the mussel C. grayanus is present at least in two suborders of bivalves: Pectinoida and Mytiloida.

Non-Straub type actin from molluscan catch muscle.

We have developed a method of obtaining natural actin from smooth muscles of the bivalves on the example of the Сrenomytilus grayanus catch muscle. The muscles were previously rigorized to prevent a loss of thin filaments during homogenization and washings. Thin filaments were isolated with a low ionic strength solution in the presence of ATP and sodium pyrophosphate. Surface proteins of thin filaments-tropomyosin, troponin, calponin and some minor actin-binding proteins-were dissociated from actin filaments by increasing the ionic strength to 0.6 M KCL. Natural fibrillar actin obtained in that way depolymerizes easily in low ionic strength solutions commonly used for the extraction of Straub-type actin from acetone powder. Purification of natural actin was carried out by the polymerization-depolymerization cycle. The content of inactivated actin remaining in the supernatant is much less than at a similar purification of Straub-type actin. A comparative investigation was performed between the natural mussel actin and the Straub-type rabbit skeletal actin in terms of the key properties of actin: polymerization, activation of Mg-ATPase activity of myosin, and the electron-microscopic structure of actin polymers.

Hybrid and non-hybrid actomyosins reconstituted with actin, myosin and tropomyosin from skeletal and catch muscles.

In this study, we investigated hybrid and non-hybrid actomyosin models including key contractile proteins: actin, myosin, and tropomyosin. These proteins were isolated from the rabbit skeletal muscle and the catch muscle of the mussel Crenomytilus grayanus. Our results confirmed literature data on an unusual ability of bivalve's tropomyosin to inhibit Mg-ATPase activity of skeletal muscle actomyosin. We have shown that the degree of inhibition depends on the environmental conditions and may vary within a wide range. The inhibitory effect of mussel tropomyosin was not detected in non-hybrid model (mussel myosin + mussel actin + mussel tropomyosin). This effect was revealed only in hybrid models containing mussel tropomyosin + rabbit (or mussel) actin + rabbit myosin. We assume that mussel and rabbit myosins have mismatched binding sites for actin. In addition, mussel tropomyosin interacting with actin is able to close the binding sites of rabbit myosin with actin, which leads to inhibition of Mg-ATPase activity.

Radiation Therapy in the Management of Leptomeningeal Disease From Solid Tumors.

Purpose: Leptomeningeal disease (LMD) is clinically detected in 5% to 10% of patients with solid tumors and is a source of substantial morbidity and mortality. Prognosis for this entity remains poor and treatments are palliative. Radiation therapy (RT) is an essential tool in the management of LMD, and a recent randomized trial demonstrated a survival benefit for proton craniospinal irradiation (CSI) in select patients. In the setting of this recent advance, we conducted a review of the role of RT in LMD from solid tumors to evaluate the evidence basis for RT recommendations. Methods and Materials: In November 2022, we conducted a comprehensive literature search in PubMed, as well as a review of ongoing clinical trials listed on ClinicalTrials.gov, to inform a discussion on the role of RT in solid tumor LMD. Because of the paucity of high-quality published evidence, discussion was informed more by expert consensus and opinion, including a review of societal guidelines, than evidence from clinical trials. Results: Only 1 prospective randomized trial has evaluated RT for LMD, demonstrating improved central nervous system progression-free survival for patients with breast and lung cancer treated with proton CSI compared with involved-field RT. Modern photon CSI techniques have improved upon historical rates of acute hematologic toxicity, but the overall benefit of this modality has not been prospectively evaluated. Multiple retrospective studies have explored the use of involved-field RT or the combination of RT with chemotherapy, but clear evidence of survival benefit is lacking. Conclusions: Optimal management of LMD with RT remains reliant upon expert opinion, with proton CSI indicated in patients with good performance status and extra-central nervous system disease that is either well-controlled or for which effective treatment options are available. Photon-based CSI traditionally has been associated with increased marrow and gastrointestinal toxicities, though intensity modulated RT/volumetric-modulated arc therapy based photon CSI may have reduced the toxicity profile. Further work is needed to understand the role of radioisotopes as well as combined modality treatment with intrathecal or central nervous system penetrating systemic therapies.

Prospective evaluation of patient-reported outcomes of invisible ink tattoos for the delivery of external beam radiation therapy: the PREFER trial.

Introduction: Invisible ink tattoos (IITs) avoid cosmetic permanence of visible ink tattoos (VITs) while serving as more reliable landmarks for radiation setup than tattooless setups. This trial evaluated patient-reported preference and feasibility of IIT implementation. Methods and materials: In an IRB-approved, single institution, prospective trial, patients receiving proton therapy underwent IIT-based treatment setup. A survey tool assessed patient preference on tattoos using a Likert scale. Matched patients treated using our institutional standard tattooless setup were identified; treatment times and image guidance requirements were evaluated between tattooless and IIT-based alignment approaches. Distribution differences were estimated using Wilcoxon rank-sum tests or Chi-square tests. Results: Of 94 eligible patients enrolled, median age was 58 years, and 58.5% were female. Most common treatment sites were breast (18.1%), lung (17.0%) and pelvic (14.9%). Patients preferred to receive IITs versus VITs (79.8% pre-treatment and 75.5% post-treatment, respectively). Patients were willing to travel farther from home to avoid VITs versus IITs (p<0.01). Females were willing to travel (45.5% vs. 23.1%; p=0.04) and pay additional money to avoid VITs (34.5% vs. 5.1%; p<0.01). Per-fraction average +treatment time and time from on table/in room to first beam were shorter with IIT-based vs. tattooless setup (12.3min vs. 14.1min; p=0.04 and 24.1min vs. 26.2min; p=0.02, respectively). Discussion: In the largest prospective trial on IIT-based radiotherapy setup to date, we found that patients prefer IITs to VITs. Additionally, IIT-based alignment is an effective and efficient strategy in comparison with tattooless setup. Standard incorporation of IITs for patient setup should be strongly considered.

Reirradiation With Proton Therapy for Recurrent Malignancies of the Esophagus and Gastroesophageal Junction: Results of the Proton Collaborative Group Multi-Institutional Prospective Registry Trial.

Purpose: Treatment options for recurrent esophageal cancer (EC) previously treated with radiation therapy (RT) are limited. Reirradiation (reRT) with proton beam therapy (PBT) can offer lower toxicities by limiting doses to surrounding tissues. In this study, we present the first multi-institutional series reporting on toxicities and outcomes after reRT for locoregionally recurrent EC with PBT. Methods and Materials: Analysis of the prospective, multicenter, Proton Collaborative Group registry of patients with recurrent EC who had previously received photon-based RT and underwent PBT reRT was performed. Patient/tumor characteristics, treatment details, outcomes, and toxicities were collected. Local control (LC), distant metastasis-free survival (DMFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Event time was determined from reRT start. Results: Between 2012 and 2020, 31 patients received reRT via uniform scanning/passive scattering (61.3%) or pencil beam scanning (38.7%) PBT at 7 institutions. Median prior RT, PBT reRT, and cumulative doses were 50.4 Gy (range, 37.5-110.4), 48.6 Gy (relative biological effectiveness) (25.2-72.1), and 99.9 Gy (79.1-182.5), respectively. Of these patients, 12.9% had 2 prior RT courses, and 67.7% received PBT with concurrent chemotherapy. Median follow-up was 7.2 months (0.9-64.7). Post-PBT, there were 16.7% locoregional only, 11.1% distant only, and 16.7% locoregional and distant recurrences. Six-month LC, DMFS, and OS were 80.5%, 83.4%, and 69.1%, respectively. One-year LC, DMFS, and OS were 67.1%, 83.4%, and 27%, respectively. Acute grade ≥3 toxicities occurred in 23% of patients, with 1 acute grade 5 toxicity secondary to esophageal hemorrhage, unclear if related to reRT or disease progression. No grade ≥3 late toxicities were reported. Conclusions: In the largest report to date of PBT for reRT in patients with recurrent EC, we observed acceptable acute toxicities and encouraging rates of disease control. However, these findings are limited by the poor prognoses of these patients, who are at high risk of mortality. Further research is needed to better assess the long-term benefits and toxicities of PBT in this specific patient population.

Molluscan smooth catch muscle contains calponin but not caldesmon.

We isolated Ca(2+)-regulated thin filaments from the smooth muscle of the mussel Crenomytilus grayanus and studied the protein composition of different preparations from this muscle: whole muscle, heat-stable extract, fractions from heat-stable extract, thin filaments and intermediate stages of thin filaments purification. Among the protein components of the above-listed preparations, we did not find caldesmon (CaD), although two isoforms of a calponin-like (CaP-like) protein, which along with CaD is characteristic of vertebrate smooth muscle, were present in thin filaments. Thus, CaD is not Ca(2+)-regulator of thin filaments of this muscle. On the other hand, the mussel CaP-like protein is also not such Ca(2+)-regulator since we have shown that this protein can be selectively removed from isolated mussel thin filaments without loss of their Ca(2+)-sensitivity. We suggest that thin filaments in the smooth catch muscle possess other type of Ca(2+)-regulation, different from that in vertebrate smooth muscles.

Racial inequity and other social disparities in the diagnosis and management of bladder cancer.

BACKGROUND: We investigate the impact of gender, race, and socioeconomic status on the diagnosis and management of bladder cancer in the United States. METHODS: We utilized the National Cancer Database to stratify cases of urothelial cell carcinoma of the bladder as early (Tis, Ta, T1), muscle invasive (T2-T3, N0), locally advanced (T4, N1-3), and metastatic. Multivariate binomial and multinomial logistic regression analyses identified demographic characteristics associated with stage at diagnosis and receipt of cancer-directed therapies. Odds ratios (OR) are reported with 95% confidence intervals. RESULTS: After exclusions, we identified 331,714 early, 72,154 muscle invasive, 15,579 locally advanced, and 15,161 metastatic cases from 2004-2016. Relative to diagnosis at early stage, the strongest independent predictors of diagnosis at muscle invasive, locally advanced, and metastatic disease included Black race (OR = 1.19 [1.15-1.23], OR = 1.49 [1.40-1.59], OR = 1.66 [1.56-1.76], respectively), female gender (OR = 1.21 [1.18-1.21], OR = 1.16 [1.12-1.20], and OR = 1.34 [1.29-1.38], respectively), and uninsured status (OR = 1.22 [1.15-1.29], OR = 2.09 [1.94-2.25], OR = 2.57 [2.39-2.75], respectively). Additional demographic factors associated with delayed diagnosis included older age, treatment at an academic center, Medicaid insurance and patients from lower income/less educated/more rural areas (all p < 0.01). Treatment at a non-academic center, older age, women, Hispanic and Black patients, lower income and rural areas were all less likely to receive cancer-directed therapies in early stage disease (all p < 0.01). Women, older patients, and Black patients remained less likely to receive treatment in muscle invasive, locally advanced, and metastatic disease (all p < 0.01). CONCLUSION: Black race was the strongest independent predictor of delayed diagnosis and substandard treatment of bladder cancer.

Immune Escape in Glioblastoma: Mechanisms of Action and Implications for Immune Checkpoint Inhibitors and CAR T-Cell Therapy.

Glioblastoma, the most common primary brain cancer in adults, is characterized by a poor prognosis and resistance to standard treatments. The advent of immunotherapy has revolutionized the treatment of several cancers in recent years but has failed to demonstrate benefit in patients with glioblastoma. Understanding the mechanisms by which glioblastoma exerts tumor-mediated immune suppression in both the tumor microenvironment and the systemic immune landscape is a critical step towards developing effective immunotherapeutic strategies. In this review, we discuss the current understanding of immune escape mechanisms in glioblastoma that compromise the efficacy of immunotherapies, with an emphasis on immune checkpoint inhibitors and chimeric antigen receptor T-cell therapy. In parallel, we review data from preclinical studies that have identified additional therapeutic targets that may enhance overall treatment efficacy in glioblastoma when administered alongside existing immunotherapies.

Efficacy and Safety of Stereotactic Body Radiation Therapy for Pediatric Malignancies: The LITE-SABR Systematic Review and Meta-Analysis.

Purpose: Limited data are currently available on clinical outcomes after stereotactic body radiation therapy (SBRT) for pediatric and adolescent and young adult (AYA) patients with cancer. We aimed to perform a systematic review and study-level meta-analysis to characterize associated local control (LC), progression-free survival (PFS), overall survival, and toxicity after SBRT. Methods and Materials: Relevant studies were queried using a Population, Intervention, Control, Outcomes, Study Design (PICOS)/Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)/Meta-analysis of Observational Studies in Epidemiology (MOOSE) selection criteria. Primary outcomes were 1-year and 2-year LC as well as incidence of acute and late grade 3 to 5 toxicities, with secondary outcomes of 1-year overall survival and 1-year PFS. Outcome effect sizes were estimated with weighted random effects meta-analyses. Mixed-effects weighted regression models were performed to examine potential correlations between biologically effective dose (BED10), LC, and toxicity incidence. Results: Across 9 published studies, we identified 142 pediatric and AYA patients with 217 lesions that were treated with SBRT. Estimated 1-year and 2-year LC rates were 83.5% (95% confidence interval, 70.9%-96.2%) and 74.0% (95% CI, 64.6%-83.4%), respectively, with an estimated acute and late grade 3 to 5 toxicity rate of 2.9% (95% CI, 0.4%-5.4%; all grade 3). The estimated 1-year OS and PFS rates were 75.4% (95% CI, 54.5%-96.3%) and 27.1% (95% CI, 17.3%-37.0%), respectively. On meta-regression, higher BED10 was correlated with improved 2-year LC with every 10 Gy10 increase in BED10 associated with a 5% improvement in 2-year LC (P = .02) in sarcoma-predominant cohorts. Conclusions: SBRT provided durable LC for pediatric and AYA patients with cancer with minimal severe toxicities. Dose escalation may result in improved LC for sarcoma-predominant cohorts without a subsequent increase in toxicity. However, further investigations with patient-level data and prospective inquiries are indicated to better define the role of SBRT based on patient and tumor-specific characteristics.

The Rise of Open Access Journals in Radiation Oncology: Influence on Resident Research, 2015 to 2019.

Purpose: While a rising share of scientific research articles are being published in open access (OA) journals, their impact on resident research in radiation oncology is unknown. Thus, we sought to determine the number, content, and costs of first-author, PubMed-searchable articles radiation oncology residents in the United States (US) published in OA journals in recent years. Methods and Materials: We built a database of first-author, PubMed-searchable articles published by US radiation oncology residents who graduated between 2015 and 2019. We then classified each journal in which these articles appeared as either OA or non-OA and obtained the current article-processing charge (APC) for each publication that appeared in an OA journal. Results: The residents in this study published 2637 first-author, PubMed-searchable articles, 555 of which (21.0%) appeared in 138 OA journals. The number of publications in OA journals per resident increased from 0.47 for the class of 2015 to 0.79 for the class of 2019. Publications in OA journals garnered fewer citations than those in non-OA journals (8.9 vs 14.9, P < .01). Furthermore, 90.6% of OA journals levy an APC for original research reports (median, $1896), which is positively correlated with their 2019 impact factor (r = 0.63, P < .01). Aggregate APCs totaled $900,319.21 and appeared to increase over the study period. Conclusions: The number of first-author, PubMed-searchable articles published by graduating US radiation oncology residents in OA journals rose significantly between 2015 and 2019. To maximize the benefits of OA publishing in the future, US radiation oncology residents will need to ensure that they use vetted OA journals to publish their research findings and avoid predatory journals.

Advances in treatment planning and management for the safety and accuracy of lung stereotactic body radiation therapy using proton pencil beam scanning: Simulation, planning, quality assurance, and delivery recommendations.

This study presents the clinical experiences of the New York Proton Center in employing proton pencil beam scanning (PBS) for the treatment of lung stereotactic body radiation therapy. It encompasses a comprehensive examination of multiple facets, including patient simulation, delineation of target volumes and organs at risk, treatment planning, plan evaluation, quality assurance, and motion management strategies. By sharing the approaches of the New York Proton Center and providing recommendations across simulation, treatment planning, and treatment delivery, it is anticipated that the valuable experience will be provided to a broader proton therapy community, serving as a useful reference for future clinical practice and research endeavors in the field of stereotactic body proton therapy for lung tumors.

The Applications and Pitfalls of Cone-Beam Computed Tomography-Based Synthetic Computed Tomography for Adaptive Evaluation in Pencil-Beam Scanning Proton Therapy.

PURPOSE: The study evaluates the efficacy of cone-beam computed tomography (CBCT)-based synthetic CTs (sCT) as a potential alternative to verification CT (vCT) for enhanced treatment monitoring and early adaptation in proton therapy. METHODS: Seven common treatment sites were studied. Two sets of sCT per case were generated: direct-deformed (DD) sCT and image-correction (IC) sCT. The image qualities and dosimetric impact of the sCT were compared to the same-day vCT. RESULTS: The sCT agreed with vCT in regions of homogeneous tissues such as the brain and breast; however, notable discrepancies were observed in the thorax and abdomen. The sCT outliers existed for DD sCT when there was an anatomy change and for IC sCT in low-density regions. The target coverage exhibited less than a 5% variance in most DD and IC sCT cases when compared to vCT. The Dmax of serial organ-at-risk (OAR) in sCT plans shows greater deviation from vCT than small-volume dose metrics (D0.1cc). The parallel OAR volumetric and mean doses remained consistent, with average deviations below 1.5%. CONCLUSION: The use of sCT enables precise treatment and prompt early adaptation for proton therapy. The quality assurance of sCT is mandatory in the early stage of clinical implementation.

Safety and efficacy of stereotactic body proton therapy for high-risk lung tumors.

Purpose: Stereotactic body proton therapy (SBPT) is an emerging treatment strategy for lung tumors that aims to combine the excellent local control benefits of ultra-hypofractionation with the physical advantages of protons, which reduce the integral dose to organs at risk (OARs) compared to photons. To date, however, very little data delivering SBPT in 5 or fewer fractions to lung tumors have been reported. Given that photon stereotactic body radiation therapy can struggle to deliver ablative doses to high-risk tumors (i.e., central/ultra-central location, prior in-field radiation, tumor size >5 cm, or the presence of severe pulmonary comorbidities) while adhering to OAR dose constraints, we hypothesized that SBPT would be an effective alternative for patients with high-risk tumors. Methods and Materials: Twenty-seven high-risk patients with 29 lung tumors treated with SBPT at the New York Proton Center between December 2019 and November 2022 were retrospectively identified. Patients were divided into three major subgroups: early-stage non-small cell lung cancer (NSCLC), locally recurrent NSCLC, and metastatic cancer from lung cancer or other histologies. Patient characteristics were reported using descriptive statistics, actuarial methods were used to quantify disease control rates, and toxicities were scored using CTCAE v 5.0. Results: The most common high-risk indications for SBPT were central/ultra-central tumor location (69.0%), severe COPD (48.1%), reirradiation (44.4%), significant pulmonary fibrosis (22.2%), and large tumor size > 5 cm (18.5%). In total, 96.6% of tumors were fully covered by the prescription dose without compromising target coverage. Three-year actuarial rates of local control for early-stage NSCLC, locally recurrent NSCLC, and metastatic patients were 89%, 100%, and 43%, respectively. Three-year actuarial rates of regional control were 89%, 67%, and 86%. Three-year actuarial rates of distant metastasis-free survival were 79%, 100%, and 0%. Two patients (7.4%), both of whom had clinically significant baseline interstitial lung disease and pre-treatment continuous oxygen demand, experienced grade ≥2 pulmonary toxicity (1 grade 3, 1 grade 5). There were no acute or late grade ≥2 toxicities related to esophagitis, cardiac injury, airway injury, pulmonary fibrosis, bronchopulmonary hemorrhage or brachial plexopathy. Conclusions: In the largest study of proton SBRT reported to date, SBPT has a favorable toxicity profile while being an effective approach for treating most high-risk tumors without requiring dose de-escalation or compromising tumor coverage and warrants further investigation.

Interleukin-1 receptor mediates the interplay between CD4+ T cells and ocular resident cells to promote keratinizing squamous metaplasia in Sjögren's syndrome.

Keratinizing squamous metaplasia (SQM) of the ocular mucosal epithelium is a blinding corneal disease characterized by the loss of conjunctival goblet cells (GCs), pathological ocular surface keratinization and tissue recruitment of immune cells. Using the autoimmune regulator (Aire)-deficient mouse as a model for Sjögren's syndrome (SS)-associated SQM, we identified CD4(+) T lymphocytes as the main immune effectors driving SQM and uncovered a pathogenic role for interleukin-1 (IL-1). IL-1, a pleiotropic cytokine family enriched in ocular epithelia, governs tissue homeostasis and mucosal immunity. Here, we used adoptive transfer of autoreactive CD4(+) T cells to dissect the mechanism whereby IL-1 promotes SQM. CD4(+) T cells adoptively transferred from both Aire knockout (KO) and Aire/IL-1 receptor type 1 (IL-1R1) double KO donors conferred SQM to severe-combined immunodeficiency (scid) recipients with functional IL-1R1, but not scid recipients lacking IL-1R1. In the lacrimal gland, IL-1R1 was primarily immunolocalized to ductal epithelium surrounded by CD4(+) T cells. In the eye, IL-1R1 was expressed on local mucosal epithelial and stromal cells, but not on resident antigen-presenting cells or infiltrating immune cells. In both tissues, autoreactive CD4(+) T-cell infiltration was only observed in the presence of IL-1R1-postive resident cells. Moreover, persistent activation of IL-1R1 signaling led to chronic immune-mediated inflammation by retaining CD4(+) T cells in the local microenvironment. Following IL-1R1-dependent infiltration of CD4(+) T cells, we observed SQM hallmarks in local tissues-corneal keratinization, conjunctival GC mucin acidification and epithelial cell hyperplasia throughout the ocular surface mucosa. Proinflammatory IL-1 expression in ocular epithelial cells significantly correlated with reduced tear secretion, while CD4(+) T-cell infiltration of the lacrimal gland predicted the development of ocular SQM. Collectively, data in this study indicated a central role for IL-1 in orchestrating a functional interplay between immune cells and resident cells of SS-targeted tissues in the pathogenesis of SQM.

Phantosmia Among Pediatric, Adolescent, and Young Adult Patients Receiving Proton Beam Therapy.

Purpose: Phantosmia, an underreported toxicity of brain radiation therapy (RT), is defined as an olfactory disorder resulting in a malodorous phantom smell. This study aimed to characterize the incidence of phantosmia in patients treated with intensity modulated proton therapy (IMPT). Methods and Materials: In this institutional review board-approved retrospective study, the electronic medical record of a pencil beam scanning-only proton center was queried for patients ≤39 years of age who received IMPT for primary intracranial, metastatic intracranial, skull base, nasopharyngeal or sinonasal neoplasms between August 2019 and December 2020. Patient, clinical, and phantosmia-related characteristics were collected. The olfactory region was defined to include the olfactory bulb and tract. Phantosmia severity was graded by intervention use (mild, no intervention; moderate, supportive treatment; severe, RT discontinuation). Results: Ninety-nine patients met the inclusion criteria. Twelve patients (12.1%) reported phantosmia. Patients described perceiving a "chlorine," "broccoli," "stale water," "metallic," or "noxious" smell. Of the patients who reported phantosmia, median age was 17 (12-33) years, 66.7% were male, and 91.7% had intracranial tumors. None of the patients had prior RT. Chemoradiotherapy treatment did not correlate with phantosmia development (odds ratio, 1.09; 95% confidence interval, 0.32-3.70; P = .90). Ten patients experienced accompanying toxicities, including taste changes (n = 3), vision disturbances (n = 5), and nausea/emesis (n = 7). Phantosmia was mild (n = 7) or moderate (n = 5). All patients completed their RT course. Sixty-seven percent received craniospinal irradiation (CSI) while 33% received focal brain RT, with the olfactory region receiving doses as low as 0.5 Gy. Notably, 8 of 27 patients who received CSI (30%) reported phantosmia (odds ratio, 7.66; 95% confidence interval, 2.07-28.34; P = .002). Conclusions: In the first-ever study examining radiation-induced phantosmia among children and young adults treated with IMPT, all affected patients received irradiation dose to the olfactory region. Physician awareness of phantosmia, especially in the context of CSI, may improve the patient experience and treatment compliance. A prospective study is needed to elucidate frequency, severity, and phantosmia mechanism.