NRG Oncology White Paper on the Relative Biological Effectiveness in Proton Therapy.

This position paper, led by the NRG Oncology Particle Therapy Work Group, focuses on the concept of relative biologic effect (RBE) in clinical proton therapy, with the goal of providing recommendation for the next generation clinical trials with proton therapy on the best practice of investigating and using RBE, which could deviate from the current standard proton RBE value of 1.1 relative to photons. In part one, current clinical utilization and practice are reviewed, giving the context and history of RBE. Evidence for variation in RBE is presented along with the concept of linear energy transfer (LET). The intertwined nature of tumor radiobiology, normal tissue constraints, and treatment planning with LET and RBE considerations is then reviewed. Part two summarizes current and past clinical data and then suggests the next steps to explore and employ tools for improved dynamic models for RBE. In part three, approaches and methods for the next generation of prospective clinical trials are explored, with the goal of optimizing RBE to be both more reflective of clinical reality and also deployable in trials to allow clinical validation and inter-patient comparisons. These concepts provide the foundation for personalized biologic treatments reviewed in part four. Finally, we conclude with a summary including short- and long-term scientific focus points for clinical proton therapy. The practicalities and capacity to use RBE in treatment planning are reviewed and considered with more biological data in hand. The intermediate step of LET optimization is summarized and proposed as a potential bridge to the ultimate goal of case-specific RBE planning that can be achieved as a hypothesis generating tool in near-term proton trials.

The ASCENT Trial: a phase 2 study of induction and consolidation afatinib and chemoradiation with or without surgery in stage III EGFR-mutant NSCLC.

BACKGROUND: The role of tyrosine kinase inhibitors (TKIs) in early-stage and metastatic oncogene-driven non-small cell lung cancer (NSCLC) is established, but it remains unknown how best to integrate TKIs with concurrent chemoradiotherapy (cCRT) in locally advanced disease. The phase 2 ASCENT trial assessed the efficacy and safety of afatinib and cCRT with or without surgery in locally advanced epidermal growth factor receptor (EGFR)-mutant NSCLC. PATIENTS AND METHODS: Adults ≥18 years with histologically confirmed stage III (AJCC 7th edition) NSCLC with activating EGFR mutations were enrolled at Mass General and Dana-Farber/Brigham Cancer Centers, Boston, Massachusetts. Patients received induction afatinib 40 mg daily for 2 months, then cisplatin 75 mg/m2 and pemetrexed 500 mg/m2 IV every 3 weeks during RT (definitive or neoadjuvant dosing). Patients with resectable disease underwent surgery. All patients were offered consolidation afatinib for 2 years. The primary endpoint was the objective response rate (ORR) to induction TKI. Secondary endpoints were safety, conversion to operability, progression-free survival (PFS), and overall survival (OS). Analyses were performed on the intention-to-treat population. RESULTS: Nineteen patients (median age 56 years; 74% female) were enrolled. ORR to induction afatinib was 63%. Seventeen patients received cCRT; 2/9 previously unresectable became resectable. Ten underwent surgery; 6 had a major or complete pathological response. Thirteen received consolidation afatinib. With a median follow-up of 5.0 years, median PFS and OS were 2.6 (95% CI, 1.4-3.1) and 5.8 years (2.9-NR), respectively. Sixteen recurred or died; 6 recurrences were isolated to CNS. The median time to progression after stopping consolidation TKI was 2.9 months (95% CI, 1.1-7.2). Four developed grade 2 pneumonitis. There were no treatment-related deaths. CONCLUSION: We explored the efficacy of combining TKI with cCRT in oncogene-driven NSCLC. Induction TKI did not compromise subsequent receipt of multimodality therapy. PFS was promising, but the prevalence of CNS-only recurrences and rapid progression after TKI discontinuation speak to unmet needs in measuring and eradicating micrometastatic disease.

Recent Trends in "Manels" and Gender Representation Among Panelists at North American Annual Radiation Oncology Meetings.

PURPOSE: Achieving gender equity in radiation oncology is an important goal, as a smaller proportion of women enter radiation oncology residency compared with those graduating from medical school. As invited speaking opportunities at academic medical conferences are vital for promotion/tenure, we investigated the prevalence of all-men panels ("manels") at American Society for Radiation Oncology (ASTRO) and Canadian Society of Radiation Oncology (CARO) annual meetings. METHODS AND MATERIALS: Using ASTRO and CARO online meeting programs, 2018 to 2021 faculty information was obtained, including gender, panel role (chair vs nonchair), type of session, and topic. Primary outcomes included percentage of manels and proportion of female panelists over time. Representation of women among chairs was also evaluated. RESULTS: Over the 4-year study period across both conferences, a total of 765 panel sessions were held with 2973 faculty members, of whom 1287 (43.3%) were women. Of these sessions, 127 of 765 (16.6%) were manels. ASTRO meetings had 1169 of 2742 (42.6%) female faculty members and held 107 of 680 (15.7%) manels, whereas CARO meetings had 118 of 231 (51.1%) female faculty and held 20 of 85 manels (23.5%). From 2018 to 2021, the proportion of manels decreased at ASTRO and CARO meetings from 25.6% to 8.2% (P < .001) and from 29.6% to 15.0% (P = .130), respectively. The role of chair was majority male in every year from 2018 to 2021 at ASTRO meetings (58.6% overall), but more balanced at CARO meetings (48.0% overall). Among session types, the highest proportion of manels was observed for scientific sessions (19.1%, P = .011) at ASTRO meetings and leadership sessions (29.4%, P = .533) at CARO meetings. The lowest proportion of female panelists was on genitourinary cancer topics at ASTRO meetings (31.9%, P = .018) and physics topics at CARO meetings (40.4%, P = .085). CONCLUSIONS: During the study period, the proportion of female panelists increased with a corresponding decrease in manels. ASTRO and CARO should strive for further involvement of women and the elimination of manels whenever possible.

ß1 integrin mediates unresponsiveness to PI3Kα inhibition for radiochemosensitization of 3D HNSCC models.

Phosphoinositide 3-kinase (PI3K)-α represents a key intracellular signal transducer involved in the regulation of key cell functions such as cell survival and proliferation. Excessive activation of PI3Kα is considered one of the major determinants of cancer therapy resistance. Despite preclinical and clinical evaluation of PI3Kα inhibitors in various tumor entities, including head and neck squamous cell carcinoma (HNSCC), it remains elusive how conventional radiochemotherapy can be enhanced by concurrent PI3K inhibitors and how PI3K deactivation mechanistically exerts its effects. Here, we investigated the radiochemosensitizing potential and adaptation mechanisms of four PI3K inhibitors, Alpelisib, Copanlisib, AZD8186, and Idelalisib in eight HNSCC models grown under physiological, three-dimensional matrix conditions. We demonstrate that Alpelisib, Copanlisib and AZD8186 but not Idelalisib enhance radio- and radiochemosensitivity in the majority of HNSCC cell models (= responders) in a manner independent of PIK3CA mutation status. However, Alpelisib promotes MAPK signaling in non-responders compared to responders without profound impact on Akt, NFκB, TGFß, JAK/STAT signaling and DNA repair. Bioinformatic analyses identified unique gene mutations associated with extracellular matrix to be more frequent in non-responder cell models than in responders. Finally, we demonstrate that targeting of the cell adhesion molecule ß1 integrin on top of Alpelisib sensitizes non-responders to radiochemotherapy. Taken together, our study demonstrates the sensitizing potential of Alpelisib and other PI3K inhibitors in HNSCC models and uncovers a novel ß1 integrin-dependent mechanism that may prove useful in overcoming resistance to PI3K inhibitors.

Multimodality Management of Thoracic Tumors: Initial Experience With a Multidisciplinary Thoracic Ablation Conference.

BACKGROUND: This study aimed to describe lesion-specific management of thoracic tumors referred for consideration of image-guided thermal ablation (IGTA) at a newly established multidisciplinary ablation conference. METHODS: This retrospective single-center cohort study included consecutive patients with non-small cell lung cancer (NSCLC) or thoracic metastases evaluated from June 2020 to January 2022 in a multidisciplinary conference. Outcomes included the management recommendation, treatments received (IGTA, surgical resection, stereotactic body radiation therapy [SBRT], multimodality management), and number of tumors treated per patient. Pearson's chi-square test was used to assess for a change in management, and Poisson regression was used to compare the number of tumors by treatment received. RESULTS: The study included 172 patients (58 % female; median age, 69 years; 56 % thoracic metastases; 27 % multifocal primary lung cancer; 59 % ECOG 0 [range, 0-3]) assessed in 206 evaluations. For the patients with NSCLC, IGTA was considered the most appropriate local therapy in 12 %, equal to SBRT in 22 %, and equal to lung resection in 3 % of evaluations. For the patients with thoracic metastases, IGTA was considered the most appropriate local therapy in 22 %, equal to SBRT in 12 %, and equal to lung resection in 3 % of evaluations. Although all patients were referred for consideration of IGTA, less than one third of patients with NSCLC or thoracic metastases underwent IGTA (p < 0.001). Multimodality management allowed for treatment of more tumors per patient than single-modality management (p < 0.01). CONCLUSIONS: Multidisciplinary evaluation of patients with thoracic tumors referred for consideration of IGTA significantly changed patient management and facilitated lesion-specific multimodality management.

Genomic Tumor Correlates of Clinical Outcomes Following Organ-Sparing Chemoradiation Therapy for Bladder Cancer.

PURPOSE: There is an urgent need for biomarkers of radiation response in organ-sparing therapies. Bladder preservation with trimodality therapy (TMT), consisting of transurethral tumor resection followed by chemoradiation, is an alternative to radical cystectomy for muscle-invasive bladder cancer (MIBC), but molecular determinants of response are poorly understood. EXPERIMENTAL DESIGN: We characterized genomic and transcriptomic features correlated with long-term response in a single institution cohort of patients with MIBC homogeneously treated with TMT. Pretreatment tumors from 76 patients with MIBC underwent whole-exome sequencing; 67 underwent matched transcriptomic profiling. Molecular features were correlated with clinical outcomes including modified bladder-intact event-free survival (mBI-EFS), a composite endpoint that reflects long-term cancer control with bladder preservation. RESULTS: With a median follow-up of 74.6 months in alive patients, 37 patients had favorable long-term response to TMT while 39 had unfavorable long-term response. Tumor mutational burden was not associated with outcomes after TMT. DNA damage response gene alterations were associated with improved locoregional control and mBI-EFS. Of these alterations, somatic ERCC2 mutations stood out as significantly associated with favorable long-term outcomes; patients with ERCC2 mutations had significantly improved mBI-EFS [HR, 0.15; 95% confidence interval (CI), 0.06-0.37; P = 0.030] and improved BI-EFS, an endpoint that includes all-cause mortality (HR, 0.33; 95% CI, 0.15-0.68; P = 0.044). ERCC2 mutant bladder cancer cell lines were significantly more sensitive to concurrent cisplatin and radiation treatment in vitro than isogenic ERCC2 wild-type cells. CONCLUSIONS: Our data identify ERCC2 mutation as a candidate biomarker associated with sensitivity and long-term response to chemoradiation in MIBC. These findings warrant validation in independent cohorts.

Pneumonitis in Patients Receiving Thoracic Radiotherapy and Osimertinib: A Multi-Institutional Study.

Introduction: Thoracic radiotherapy (TRT) is increasingly used in patients receiving osimertinib for advanced NSCLC, and the risk of pneumonitis is not established. We investigated the risk of pneumonitis and potential risk factors in this population. Methods: We performed a multi-institutional retrospective analysis of patients under active treatment with osimertinib who received TRT between April 2016 and July 2022 at two institutions. Clinical characteristics, including whether osimertinib was held during TRT and pneumonitis incidence and grade (Common Terminology Criteria for Adverse Events version 5.0) were documented. Logistic regression analysis was performed to identify risk factors associated with grade 2 or higher (2+) pneumonitis. Results: The median follow-up was 10.2 months (range: 1.9-53.2). Of 102 patients, 14 (13.7%) developed grade 2+ pneumonitis, with a median time to pneumonitis of 3.2 months (range: 1.5-6.3). Pneumonitis risk was not significantly increased in patients who continued osimertinib during TRT compared with patients who held osimertinib during TRT (9.1% versus 15.0%, p = 0.729). Three patients (2.9%) had grade 3 pneumonitis, none had grade 4, and two patients had grade 5 events (2.0%, diagnosed 3.2 mo and 4.4 mo post-TRT). Mean lung dose was associated with the development of grade 2+ pneumonitis in multivariate analysis (OR = 1.19, p = 0.021). Conclusions: Although the overall rate of pneumonitis in patients receiving TRT and osimertinib was relatively low, there was a small risk of severe toxicity. The mean lung dose was associated with an increased risk of developing pneumonitis. These findings inform decision-making for patients and providers.

US Cancer Mortality Trends Among Hispanic Populations From 1999 to 2020.

Importance: Advances in cancer research and treatment access have led to decreasing cancer mortality in the US; however, cancer remains the leading cause of death among Hispanic individuals. Objective: To evaluate longitudinal cancer mortality trends from 1999 to 2020 among Hispanic individuals by demographic characteristics and to compare age-adjusted cancer death rates between the Hispanic population and other racial and ethnic populations during 2000, 2010, and 2020. Design, Setting, and Participants: This cross-sectional study obtained age-adjusted cancer death rates among Hispanic individuals of all ages between January 1999 and December 2020, using the Centers for Disease Control and Prevention WONDER database. Cancer death rates in other racial and ethnic populations were extracted for 2000, 2010, and 2020. Data were analyzed from October 2021 to December 2022. Exposures: Age, gender, race, ethnicity, cancer type, and US census region. Main Outcomes and Measures: Trends and average annual percent changes (AAPCs) in age-adjusted cancer-specific mortality (CSM) rates among Hispanic individuals were estimated by cancer type, age, gender, and region. Results: From 1999 to 2020, 12 644 869 patients died of cancer in the US, of whom 690 677 (5.5%) were Hispanic; 58 783 (0.5%) were non-Hispanic American Indian or Alaska Native; 305 386 (2.4%), non-Hispanic Asian or Pacific Islander; 1 439 259 (11.4%), non-Hispanic Black or African American; and 10 124 361 (80.1%), non-Hispanic White. For 26 403 patients (0.2%), no ethnicity was stated. The overall CSM rate among Hispanic individuals decreased by 1.3% (95% CI, 1.2%-1.3%) annually. Overall CSM rate decreased more for Hispanic men (AAPC, -1.6%; 95% CI, -1.7% to -1.5%) compared with women (AAPC, -1.0%; 95% CI, -1.0% to -0.9%). While death rates among Hispanic individuals decreased for most cancer types, mortality rates for liver cancer (AAPC, 1.0%; 95% CI, 0.6%-1.4%) increased among Hispanic men, and rates of liver (AAPC, 1.0%; 95% CI, 0.8%-1.3%), pancreas (AAPC, 0.2%; 95% CI, 0.1%-0.4%), and uterine (AAPC, 1.6%; 95% CI, 1.0%-2.3%) cancers increased among Hispanic women. Overall CSM rates increased for Hispanic men aged 25 to 34 years (AAPC, 0.7%; 95% CI, 0.3%-1.1%). By US region, liver cancer mortality rates increased significantly in the West for both Hispanic men (AAPC, 1.6%; 95% CI, 0.9%-2.2%) and Hispanic women (AAPC, 1.5%; 95% CI, 1.1%-1.9%). There were differential findings in mortality rates when comparing Hispanic individuals with individuals belonging to other racial and ethnic populations. Conclusions and Relevance: In this cross-sectional study, despite overall CSM decreasing over 2 decades among Hispanic individuals, disaggregation of data demonstrated that rates of liver cancer deaths among Hispanic men and women and pancreas and uterine cancer deaths among Hispanic women increased from 1999 to 2020. There were also disparities in CSM rates among age groups and US regions. The findings suggest that sustainable solutions need to be implemented to reverse these trends among Hispanic populations.

Implementation of Machine Learning Models to Ensure Radiotherapy Quality for Multicenter Clinical Trials: Report from a Phase III Lung Cancer Study.

The outcome of the patient and the success of clinical trials involving RT is dependent on the quality assurance of the RT plans. Knowledge-based Planning (KBP) models using data from a library of high-quality plans have been utilized in radiotherapy to guide treatment. In this study, we report on the use of these machine learning tools to guide the quality assurance of multicenter clinical trial plans. The data from 130 patients submitted to RTOG1308 were included in this study. Fifty patient cases were used to train separate photon and proton models on a commercially available platform based on principal component analysis. Models evaluated 80 patient cases. Statistical comparisons were made between the KBP plans and the original plans submitted for quality evaluation. Both photon and proton KBP plans demonstrate a statistically significant improvement of quality in terms of organ-at-risk (OAR) sparing. Proton KBP plans, a relatively emerging technique, show more improvements compared with photon plans. The KBP proton model is a useful tool for creating proton plans that adhere to protocol requirements. The KBP tool was also shown to be a useful tool for evaluating the quality of RT plans in the multicenter clinical trial setting.

Recent trends of "manels": gender representation among invited panelists at an international oncology conference.

BACKGROUND: Gender disparities in academic medicine are a long-acknowledged concern, particularly at medical conferences. We investigated gender representation and prevalence of "manels" (all-men panels) among invited speakers at the 2018-2021 American Society of Clinical Oncology Annual Meetings. METHODS: Using American Society of Clinical Oncology online programs, 2018-2021 faculty information was obtained, including perceived or self-reported gender, medical specialty, session type, and topic. Primary outcomes were percentage of manels and proportion of women panelists over time; women representation among specialties and topics were evaluated. Cochran-Armitage and Fisher's exact tests were used to analyze trends in proportion of manels and women representation over time and to compare each session type, topic, or specialty with other categories combined, respectively. RESULTS: During 2018-2021, there were 670 sessions, 81 of which (12.1%) were manels. Among 2475 panelists, 1181 (47.7%) were women. Over time, the percentage of manels significantly decreased from 17.4% in 2018 to 9.9% in 2021 (P = .030). The highest proportion of manels was observed for leadership or special sessions (17.1%, P = .419). Women panelists were underrepresented for the topics of genitourinary cancers (38.6%, P = .029) and translational or preclinical sciences (36.7%, P < .001). There was a positive trend toward improved women representation among translational or preclinical sciences (27.4% in 2018 vs 41.8% in 2021, P = .031) but not among genitourinary cancers (41.1% in 2018 vs 40.7% in 2021, P = .969). CONCLUSIONS: The number of women panelists increased during the study period, with a corresponding decrease in the proportion of manels, specifically in education and leadership or special sessions. Ongoing underrepresentation of women in genitourinary cancers and translational or preclinical topics underscores the importance of annual meeting organizers continuing to strive for diverse gender representation.

Racial and ethnic disparities in a real-world precision oncology data registry.

Biorepositories enable precision oncology research by sharing clinically annotated genomic data, but it remains unknown whether these data registries reflect the true distribution of cancers in racial and ethnic minorities. Our analysis of Project Genomics Evidence Neoplasia Information Exchange (GENIE), a real-world cancer data registry designed to accelerate precision oncology discovery, indicates that minorities do not have sufficient representation, which may impact the validity of studies directly comparing mutational profiles between racial/ethnic groups and limit generalizability of biomarker discoveries to all populations.

ß-Endorphin mediates radiation therapy fatigue.

Fatigue is a common adverse effect of external beam radiation therapy in cancer patients. Mechanisms causing radiation fatigue remain unclear, although linkage to skin irradiation has been suggested. ß-Endorphin, an endogenous opioid, is synthesized in skin following genotoxic ultraviolet irradiation and acts systemically, producing addiction. Exogenous opiates with the same receptor activity as ß-endorphin can cause fatigue. Using rodent models of radiation therapy, exposing tails and sparing vital organs, we tested whether skin-derived ß-endorphin contributes to radiation-induced fatigue. Over a 6-week radiation regimen, plasma ß-endorphin increased in rats, paralleled by opiate phenotypes (elevated pain thresholds, Straub tail) and fatigue-like behavior, which was reversed in animals treated by the opiate antagonist naloxone. Mechanistically, all these phenotypes were blocked by opiate antagonist treatment and were undetected in either ß-endorphin knockout mice or mice lacking keratinocyte p53 expression. These findings implicate skin-derived ß-endorphin in systemic effects of radiation therapy. Opioid antagonism may warrant testing in humans as treatment or prevention of radiation-induced fatigue.

Utility of Noncancerous Chest CT Features for Predicting Overall Survival and Noncancer Death in Patients With Stage I Lung Cancer Treated With Stereotactic Body Radiotherapy.

BACKGROUND. Noncancerous imaging markers can be readily derived from pre-treatment diagnostic and radiotherapy planning chest CT examinations. OBJECTIVE. The purpose of this article was to explore the ability of noncancerous features on chest CT to predict overall survival (OS) and noncancer-related death in patients with stage I lung cancer treated with stereotactic body radiation therapy (SBRT). METHODS. This retrospective study included 282 patients (168 female, 114 male; median age, 75 years) with stage I lung cancer treated with SBRT between January 2009 and June 2017. Pretreatment chest CT was used to quantify coronary artery calcium (CAC) score, pulmonary artery (PA)-to-aorta ratio, emphysema, and body composition in terms of the cross-sectional area and attenuation of skeletal muscle and subcutaneous adipose tissue at the T5, T8, and T10 vertebral levels. Associations of clinical and imaging features with OS were quantified using a multivariable Cox proportional hazards (PH) model. Penalized multivariable Cox PH models to predict OS were constructed using clinical features only and using both clinical and imaging features. The models' discriminatory ability was assessed by constructing time-varying ROC curves and computing AUC at prespecified times. RESULTS. After a median OS of 60.8 months (95% CI, 55.8-68.0), 148 (52.5%) patients had died, including 83 (56.1%) with noncancer deaths. Higher CAC score (11-399: hazard ratio [HR], 1.83 [95% CI, 1.15-2.91], p = .01; ≥ 400: HR, 1.63 [95% CI, 1.01-2.63], p = .04), higher PA-to-aorta ratio (HR, 1.33 [95% CI, 1.16-1.52], p < .001, per 0.1-unit increase), and lower thoracic skeletal muscle index (HR, 0.88 [95% CI, 0.79-0.98], p = .02, per 10-cm2/m2 increase) were independently associated with shorter OS. Discriminatory ability for 5-year OS was greater for the model including clinical and imaging features than for the model including clinical features only (AUC, 0.75 [95% CI, 0.68-0.83] vs 0.61 [95% CI, 0.53-0.70]; p < .01). The model's most important clinical or imaging feature according to mean standardized regression coefficients was the PA-to-aorta ratio. CONCLUSION. In patients undergoing SBRT for stage I lung cancer, higher CAC score, higher PA-to-aorta ratio, and lower thoracic skeletal muscle index independently predicted worse OS. CLINICAL IMPACT. Noncancerous imaging features on chest CT performed before SBRT improve survival prediction compared with clinical features alone.

Incidence of Radiation Therapy Among Patients Enrolled in a Multidisciplinary Pulmonary Nodule and Lung Cancer Screening Clinic.

Importance: The number of pulmonary nodules discovered incidentally or through screening programs has increased markedly. Multidisciplinary review and management are recommended, but the involvement of radiation oncologists in this context has not been defined. Objective: To assess the role of stereotactic body radiation therapy among patients enrolled in a lung cancer screening program. Design, Setting, and Participants: This prospective cohort study was performed at a pulmonary nodule and lung cancer screening clinic from October 1, 2012, to September 31, 2019. Referrals were based on chest computed tomography with Lung Imaging Reporting and Data System category 4 finding or an incidental nodule 6 mm or larger. A multidisciplinary team of practitioners from radiology, thoracic surgery, pulmonology, medical oncology, and radiation oncology reviewed all nodules and coordinated workup and treatment as indicated. Exposures: Patients referred to the pulmonary nodule and lung cancer screening clinic with an incidental or screen-detected pulmonary nodule. Main Outcomes and Measures: The primary outcome was the proportion of patients undergoing therapeutic intervention with radiation therapy, stratified by the route of detection of their pulmonary nodules (incidental vs screen detected). Secondary outcomes were 2-year local control and metastasis-free survival. Results: Among 1150 total patients (median [IQR] age, 66.5 [59.3-73.7] years; 665 [57.8%] female; 1024 [89.0%] non-Hispanic White; 841 [73.1%] current or former smokers), 234 (20.3%) presented with screen-detected nodules and 916 (79.7%) with incidental nodules. For patients with screen-detected nodules requiring treatment, 41 (17.5%) received treatment, with 31 (75.6%) undergoing surgery and 10 (24.4%) receiving radiation therapy. Patients treated with radiation therapy were older (median [IQR] age, 73.8 [67.1 to 82.1] vs 67.6 [61.0 to 72.9] years; P < .001) and more likely to have history of tobacco use (67 [95.7%] vs 128 [76.6%]; P = .001) than those treated with surgery. Fifty-eight patients treated with radiation therapy (82.9%) were considered high risk for biopsy, and treatment recommendations were based on a clinical diagnosis of lung cancer after multidisciplinary review. All screened patients who received radiation therapy had stage I disease and were treated with stereotactic body radiation therapy. For all patients receiving stereotactic body radiation therapy, 2-year local control was 96.3% (95% CI, 91.1%-100%) and metastasis-free survival was 94.2% (95% CI, 87.7%-100%). Conclusions and Relevance: In this unique prospective cohort, 1 in 4 patients with screen-detected pulmonary nodules requiring intervention were treated with stereotactic body radiation therapy. This finding highlights the role of radiation therapy in a lung cancer screening population and the importance of including radiation oncologists in the multidisciplinary management of pulmonary nodules.

Immunogenicity and Reactogenicity of SARS-CoV-2 Vaccines in Patients With Cancer: The CANVAX Cohort Study.

PURPOSE: The immunogenicity and reactogenicity of SARS-CoV-2 vaccines in patients with cancer are poorly understood. METHODS: We performed a prospective cohort study of adults with solid-organ or hematologic cancers to evaluate anti-SARS-CoV-2 immunoglobulin A/M/G spike antibodies, neutralization, and reactogenicity ≥ 7 days following two doses of mRNA-1273, BNT162b2, or one dose of Ad26.COV2.S. We analyzed responses by multivariate regression and included data from 1,638 healthy controls, previously reported, for comparison. RESULTS: Between April and July 2021, we enrolled 1,001 patients; 762 were eligible for analysis (656 had neutralization measured). mRNA-1273 was the most immunogenic (log10 geometric mean concentration [GMC] 2.9, log10 geometric mean neutralization titer [GMT] 2.3), followed by BNT162b2 (GMC 2.4; GMT 1.9) and Ad26.COV2.S (GMC 1.5; GMT 1.4; P < .001). The proportion of low neutralization (< 20% of convalescent titers) among Ad26.COV2.S recipients was 69.9%. Prior COVID-19 infection (in 7.1% of the cohort) was associated with higher responses (P < .001). Antibody titers and neutralization were quantitatively lower in patients with cancer than in comparable healthy controls, regardless of vaccine type (P < .001). Receipt of chemotherapy in the prior year or current steroids were associated with lower antibody levels and immune checkpoint blockade with higher neutralization. Systemic reactogenicity varied by vaccine and correlated with immune responses (P = .002 for concentration, P = .016 for neutralization). In 32 patients who received an additional vaccine dose, side effects were similar to prior doses, and 30 of 32 demonstrated increased antibody titers (GMC 1.05 before additional dose, 3.17 after dose). CONCLUSION: Immune responses to SARS-CoV-2 vaccines are modestly impaired in patients with cancer. These data suggest utility of antibody testing to identify patients for whom additional vaccine doses may be effective and appropriate, although larger prospective studies are needed.

Heterogeneous immunogenicity of SARS-CoV-2 vaccines in cancer patients receiving radiotherapy.

The immunogenicity of SARS-CoV-2 vaccines in cancer patients receiving radiotherapy is unknown. This prospective cohort study demonstrates that anti-SARS-CoV-2 spike antibody and neutralization titers are reduced in a subset of thoracic radiotherapy patients, possibly due to immunosuppressive conditions. Antibody testing may be useful to identify candidates for additional vaccine doses.

Racial and Ethnic Disparities Among Participants in Precision Oncology Clinical Studies.

Importance: Precision oncology is revolutionizing cancer care, allowing for personalized treatments to improve outcomes. Cancer research has benefitted from well-designed studies incorporating precision medicine objectives, but it is unclear if these studies are representative of the diverse cancer population. Objective: To evaluate racial and ethnic representation in breast, prostate, lung, and colorectal cancer studies incorporating precision oncology objectives in the Clinicaltrials.gov registry and compare with the incidence of these cancer types in racial and ethnic minority groups in the US population. Design, Setting, and Participants: This cross-sectional study identified US-based breast, prostate, lung, and colorectal cancer studies incorporating precision oncology objectives for reporting of race and ethnicity. The Surveillance, Epidemiology, and End Results and US Census databases were used to determine cancer incidence by race and ethnicity, linked with cancer type and median year of enrollment for each trial. Data were collected and analyzed between December 2020 and April 2021. Main Outcomes and Measures: The expected number of participants per study by each racial and ethnic group was calculated based on the corresponding US-based proportion. Under- and overrepresentation was defined as the ratio of the actual number of enrolled cases to the expected number of cases for each trial by cancer type. Ratios above 1 indicated overrepresentation while a ratio below 1 indicated underrepresentation. Random-effects meta-analysis of representation ratios of individual trials was performed to weigh each individual study. Results: Of 93 studies encompassing 5867 enrollees with race and ethnicity data; 4826 participants (82.3%) were non-Hispanic White, 587 (10.0%) were Black, and 238 (4.1%) were Asian. Per observed-to-expected ratios, White participants were overrepresented in all studies, with a ratio of 1.35 (95% CI, 1.30-1.37), as well as Asian participants, with a ratio of 1.46 (95% CI, 1.28-1.66), while Black participants (ratio, 0.49; 95% CI, 0.45-0.54), Hispanic participants (ratio, 0.24; 95% CI, 0.20-0.28), and American Indian and Alaskan Native participants (ratio, 0.43; 95% CI, 0.24-0.78) were underrepresented. By individual cancer site, White participants were consistently overrepresented in all studies, while Black and Hispanic participants were underrepresented. Conclusions and Relevance: This analysis found that precision oncology studies for breast, lung, prostate, and colorectal cancers vastly underrepresent racial and ethnic minority populations relative to their cancer incidence in the US population. It is imperative to increase diversity among enrollees so that all individuals may benefit from cancer research breakthroughs and personalized treatments.

Automated clinical target volume delineation using deep 3D neural networks in radiation therapy of Non-small Cell Lung Cancer.

BACKGROUND AND PURPOSE: Clinical targeted volume (CTV) delineation accounting for the patient-specific microscopic tumor spread can be a difficult step in defining the treatment volume. We developed an intelligent and automated CTV delineation system for locally advanced non-small cell lung carcinoma (NSCLC) to cover the microscopic tumor spread while avoiding organs-at-risk (OAR). MATERIALS AND METHODS: A 3D UNet with a customized loss function was used, which takes both the patients' respiration-correlated ("4D") CT scan and the physician contoured internal gross target volume (iGTV) as inputs, and outputs the CTV delineation. Among the 84 identified patients, 60 were randomly selected to train the network, and the remaining as testing. The model performance was evaluated and compared with cropped expansions using the shape similarities to the physicians' contours (the ground-truth) and the avoidance of critical OARs. RESULTS: On the testing datasets, all model-predicted CTV contours followed closely to the ground truth, and were acceptable by physicians. The average dice score was 0.86. Our model-generated contours demonstrated better agreement with the ground-truth than the cropped 5 mm/8 mm expansion method (median of median surface distance of 1.0 mm vs 1.9 mm/2.0 mm), with a small overlap volume with OARs (0.4 cm3 for the esophagus and 1.2 cm3 for the heart). CONCLUSIONS: The CTVs generated by our CTV delineation system agree with the physician's contours. This approach demonstrates the capability of intelligent volumetric expansions with the potential to be used in clinical practice.