The International Association for the Study of Lung Cancer Thymic Epithelial Tumor Staging Project: A Re-Assessment of the International Thymic Malignancy Interest Group/International Association for the Study of Lung Cancer Lymph Node Map for Thymic Epithelial Tumors for the Forthcoming Ninth Edition of the TNM Classification of Malignant Tumors.

INTRODUCTION: A lymph node map is the pillar on which accurate assignment and documentation of nodal classification stands. The International Thymic Malignancy Interest Group created the first map for thymic epithelial malignancies in conjunction with the eighth edition of the TNM classification, representing the first official TNM classification of thymic epithelial malignancies. The map was based on clinical experience and published studies, but it was largely empirical because of limited available data. Dissemination of the map and implementation of a standard thymic stage classification across the world in 2017 have provided more consistent and granular data. METHODS: More than twice as many cases of node involvement are available for analysis in the current database compared with that of the eighth edition database, allowing validation of many aspects of the eighth edition map. This article details the process and considerations for refinement of the thymic map for the ninth TNM used by the Thymic Domain of the Staging and Prognostic Factors Committee of the International Association for the Study of Lung Cancer. The committee evaluated a large international collaborative data set, published anatomical and clinical studies pertaining to lymph node spread from thymic epithelial tumors, in conjunction with the analysis underlying refinements of the TNM components for the ninth edition TNM classification. RESULTS: The node map boundaries of the N1 and N2 categories remain unchanged. Visual clarifications have been added to the nomenclature of nodal stations within these regions. CONCLUSIONS: On the basis of the recommendation to keep the N component unchanged for the ninth edition TNM classification, the lymph node map remains unchanged as well; however, clarifications have been added to facilitate clinical use.

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.

Cost-effectiveness analysis of statins for the treatment of hospitalized COVID-19 patients.

BACKGROUND: A recent systematic review and meta-analysis reporting on thirteen published cohorts investigating 110,078 patients demonstrated that patients who were administered statins after their COVID-19 diagnosis and hospitalization were had a lower risk of mortality. While these findings are encouraging, given competing COVID-19 treatment approaches, it is unclear if statin use should be prioritized and if its use is a cost-effective treatment options for hospitalized COVID-19 patients. In this study, we report on a cost-effectiveness analysis of statin-containing treatment regimens for hospitalized COVID-19 patients. METHODS: A Markov model was used to compare statin use and no statin use among hospitalized COVID-19 patients from a United States healthcare perspective. The cycle length was one week, with a time horizon of 4 weeks. A Monte Carlo microsimulation with 20,000 samples were used. All analyses were conducted using TreeAge Pro Healthcare Version 2021 R1.1. RESULTS: The mean cost for patients receiving statins in addition to usual care was $31,623 (SD $20,331), whereas the mean cost for patients not receiving statins was $33,218 (SD $25,440). The mean effectiveness for the two cohorts were 1.73 (SD 0.96) and 1.71 (SD 1.00), respectively. CONCLUSIONS: This analysis demonstrated that treatment of hospitalized COVID-19 patients with statins was both cheaper and more effective than treatment without statins; statin-containing therapy dominates over non-statin therapy. Statin medications for the treatment of COVID-19 should be further investigated in randomized controlled trials, especially considering its cost-effective nature. Optimistically and pending the results of future randomized trials, statins should be considered for use broadly for the treatment of hospitalized COVID-19 patients.

NRG Oncology Survey of Monte Carlo Dose Calculation Use in US Proton Therapy Centers.

PURPOSE/OBJECTIVES: Monte Carlo (MC) dose calculation has appeared in primary commercial treatment-planning systems and various in-house platforms. Dual-energy computed tomography (DECT) and metal artifact reduction (MAR) techniques complement MC capabilities. However, no publications have yet reported how proton therapy centers implement these new technologies, and a national survey is required to determine the feasibility of including MC and companion techniques in cooperative group clinical trials. MATERIALS/METHODS: A 9-question survey was designed to query key clinical parameters: scope of MC utilization, validation methods for heterogeneities, clinical site-specific imaging guidance, proton range uncertainties, and how implants are handled. A national survey was distributed to all 29 operational US proton therapy centers on 13 May 2019. RESULTS: We received responses from 25 centers (86% participation). Commercial MC was most commonly used for primary plan optimization (16 centers) or primary dose evaluation (18 centers), while in-house MC was used more frequently for secondary dose evaluation (7 centers). Based on the survey, MC was used infrequently for gastrointestinal, genitourinary, gynecology and extremity compared with other more heterogeneous disease sites (P < .007). Although many centers had published DECT research, only 3/25 centers had implemented DECT clinically, either in the treatment-planning system or to override implant materials. Most centers (64%) treated patients with metal implants on a case-by-case basis, with a variety of methods reported. Twenty-four centers (96%) used MAR images and overrode the surrounding tissue artifacts; however, there was no consensus on how to determine metal dimension, materials density, or stopping powers. CONCLUSION: The use of MC for primary dose calculation and optimization was prevalent and, therefore, likely feasible for clinical trials. There was consensus to use MAR and override tissues surrounding metals but no consensus about how to use DECT and MAR for human tissues and implants. Development and standardization of these advanced technologies are strongly encouraged for vendors and clinical physicists.

Quantitative Assessment of 3D Dose Rate for Proton Pencil Beam Scanning FLASH Radiotherapy and Its Application for Lung Hypofractionation Treatment Planning.

To quantitatively assess target and organs-at-risk (OAR) dose rate based on three proposed proton PBS dose rate metrics and study FLASH intensity-modulated proton therapy (IMPT) treatment planning using transmission beams. An in-house FLASH planning platform was developed to optimize transmission (shoot-through) plans for nine consecutive lung cancer patients previously planned with proton SBRT. Dose and dose rate calculation codes were developed to quantify three types of dose rate calculation methods (dose-averaged dose rate (DADR), average dose rate (ADR), and dose-threshold dose rate (DTDR)) based on both phantom and patient treatment plans. Two different minimum MU/spot settings were used to optimize two different dose regimes, 34-Gy in one fraction and 45-Gy in three fractions. The OAR sparing and target coverage can be optimized with good uniformity (hotspot < 110% of prescription dose). ADR, accounting for the spot dwelling and scanning time, gives the lowest dose rate; DTDR, not considering this time but a dose-threshold, gives an intermediate dose rate, whereas DADR gives the highest dose rate without considering any time or dose-threshold. All three dose rates attenuate along the beam direction, and the highest dose rate regions often occur on the field edge for ADR and DTDR, whereas DADR has a better dose rate uniformity. The differences in dose rate metrics have led a large variation for OARs dose rate assessment, posing challenges to FLASH clinical implementation. This is the first attempt to study the impact of the dose rate models, and more investigations and evidence for the details of proton PBS FLASH parameters are needed to explore the correlation between FLASH efficacy and the dose rate metrics.

Photon GRID Radiation Therapy: A Physics and Dosimetry White Paper from the Radiosurgery Society (RSS) GRID/LATTICE, Microbeam and FLASH Radiotherapy Working Group.

The limits of radiation tolerance, which often deter the use of large doses, have been a major challenge to the treatment of bulky primary and metastatic cancers. A novel technique using spatial modulation of megavoltage therapy beams, commonly referred to as spatially fractionated radiation therapy (SFRT) (e.g., GRID radiation therapy), which purposefully maintains a high degree of dose heterogeneity across the treated tumor volume, has shown promise in clinical studies as a method to improve treatment response of advanced, bulky tumors. Compared to conventional uniform-dose radiotherapy, the complexities of megavoltage GRID therapy include its highly heterogeneous dose distribution, very high prescription doses, and the overall lack of experience among physicists and clinicians. Since only a few centers have used GRID radiation therapy in the clinic, wide and effective use of this technique has been hindered. To date, the mechanisms underlying the observed high tumor response and low toxicity are still not well understood. To advance SFRT technology and planning, the Physics Working Group of the Radiosurgery Society (RSS) GRID/Lattice, Microbeam and Flash Radiotherapy Working Groups, was established after an RSS-NCI Workshop. One of the goals of the Physics Working Group was to develop consensus recommendations to standardize dose prescription, treatment planning approach, response modeling and dose reporting in GRID therapy. The objective of this report is to present the results of the Physics Working Group's consensus that includes recommendations on GRID therapy as an SFRT technology, field dosimetric properties, techniques for generating GRID fields, the GRID therapy planning methods, documentation metrics and clinical practice recommendations. Such understanding is essential for clinical patient care, effective comparisons of outcome results, and for the design of rigorous clinical trials in the area of SFRT. The results of well-conducted GRID radiation therapy studies have the potential to advance the clinical management of bulky and advanced tumors by providing improved treatment response, and to further develop our current radiobiology models and parameters of radiation therapy design.

Gender-based Disparities in Receipt of Care and Survival in Malignant Pleural Mesothelioma.

BACKGROUND: Despite accounting for a minority of malignant pleural mesothelioma (MPM) diagnoses, females may experience differential survival relative to males. It is unclear if there are gender-based differences in receipt of treatment or disease-related outcomes for patients with MPM. We therefore utilized the National Cancer Database (NCDB) to assess patterns-of-care and overall survival (OS) among patients with MPM by gender. MATERIALS AND METHODS: Patients with histologically confirmed MPM treated from 2004 to 2013 were identified from the NCDB. The association between female gender and OS was assessed using multivariable Cox proportional hazards models with propensity score matching. Patterns-of-care were assessed using multivariable logistic regression. The overall treatment effect was tested in subsets of patients by treatment strategy, histology, and clinical stage. RESULTS: A total of 18,799 patients were identified, of whom 14,728 (78%) were male and 4071 (22%) were female. Females were statistically more likely to present at a younger age, with fewer comorbidities, and with epithelioid histology. Despite these favorable prognostic features, women were less likely to receive surgery (P ≤ .001) or chemotherapy (P ≤ .001) compared with males. On multivariable analysis, female gender was associated with improved OS (hazard ratio, 0.83; 95% confidence interval, 0.80-0.86; P ≤ .001). Gender-based survival differences were seen across all stages, but only among patients with epithelioid (P ≤ .001) and not biphasic (P = .17) or sarcomatoid (P = 1.00) histology. CONCLUSIONS: Surgery and chemotherapy are disproportionately underutilized in female patients with MPM. Despite this concerning disparity, female gender is independently associated with improved survival relative to males. Further research to understand factors that lead to gender disparities in MPM is warranted.

Practice Recommendations for Lung Cancer Radiotherapy During the COVID-19 Pandemic: An ESTRO-ASTRO Consensus Statement.

BACKGROUND: The COVID-19 pandemic has caused radiotherapy resource pressures and led to increased risks for lung cancer patients and healthcare staff. An international group of experts in lung cancer radiotherapy established this practice recommendation pertaining to whether and how to adapt radiotherapy for lung cancer in the COVID-19 pandemic. METHODS: For this ESTRO & ASTRO endorsed project, 32 experts in lung cancer radiotherapy contributed to a modified Delphi consensus process. We assessed potential adaptations of radiotherapy in two pandemic scenarios. The first, an early pandemic scenario of risk mitigation, is characterized by an altered risk-benefit ratio of radiotherapy for lung cancer patients due to their increased susceptibility for severe COVID-19 infection, and minimization of patient travelling and exposure of radiotherapy staff. The second, a later pandemic scenario, is characterized by reduced radiotherapy resources requiring patient triage. Six common lung cancer cases were assessed for both scenarios: peripherally located stage I NSCLC, locally advanced NSCLC, postoperative radiotherapy after resection of pN2 NSCLC, thoracic radiotherapy and prophylactic cranial irradiation for limited stage SCLC and palliative thoracic radiotherapy for stage IV NSCLC. RESULTS: In a risk-mitigation pandemic scenario, efforts should be made not to compromise the prognosis of lung cancer patients by departing from guideline-recommended radiotherapy practice. In that same scenario, postponement or interruption of radiotherapy treatment of COVID-19 positive patients is generally recommended to avoid exposure of cancer patients and staff to an increased risk of COVID-19 infection. In a severe pandemic scenario characterized by reduced resources, if patients must be triaged, important factors for triage include potential for cure, relative benefit of radiation, life expectancy, and performance status. Case-specific consensus recommendations regarding multimodality treatment strategies and fractionation of radiotherapy are provided. CONCLUSION: This joint ESTRO-ASTRO practice recommendation established pragmatic and balanced consensus recommendations in common clinical scenarios of radiotherapy for lung cancer in order to address the challenges of the COVID-19 pandemic.

Insurance Status is an Independent Predictor of Overall Survival in Patients With Stage III Non-small-cell Lung Cancer Treated With Curative Intent.

INTRODUCTION: Population studies suggest an impact of insurance status on oncologic outcomes. We sought to explore this in a large single-institution cohort of patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: We retrospectively analyzed 342 consecutive patients (January 2000 to December 2013) curatively treated for stage III NSCLC. Patients were categorized by insurance status as uninsured (U), Medicare/Medicaid + Veterans Affairs (M/M + VA), or Private (P). The χ2 test was utilized to compare categorical variables. The Kaplan-Meier approach and the Cox proportional hazard models were used to analyze overall survival (OS) and freedom from recurrence (FFR). RESULTS: Compared with M/M + VA patients, P insurance patients were more likely to be younger (P < .001), married (P < .001), Caucasian (P = .001), reside in higher median income zip codes (P < .001), have higher performance status (P < .001), and undergo consolidation chemotherapy (P < .001) and trimodality therapy (P < .001). Diagnosis to treatment was delayed > 30 days in U (67.3%), M/M + VA (68.1%), and P (52.6%) patients (P = .017). Compared with the M/M + VA and U cohorts, P insurance patients had improved OS (median/5-year: 30.7 months/34.2%, 19 months/17%, and 16.9 months/3.8%; P < .001) and FFR (median/5-year: 18.4 months/27.3%, 15.2 months/23.2%, and 11.4 months/4.8%; P = .012), respectively. On multivariate analysis, insurance status was an independent predictor for OS (P = .017) but not FFR. CONCLUSION: Compared with U or M/M + VA patients, P insurance patients with stage III NSCLC were more likely to be optimally diagnosed and treated, resulting in a doubling of median OS for P versus U patients. Improved access to affordable health insurance is critical to combat inequities in access to care and has potential for improvements in cancer outcomes.

Building more accurate decision trees with the additive tree.

The expansion of machine learning to high-stakes application domains such as medicine, finance, and criminal justice, where making informed decisions requires clear understanding of the model, has increased the interest in interpretable machine learning. The widely used Classification and Regression Trees (CART) have played a major role in health sciences, due to their simple and intuitive explanation of predictions. Ensemble methods like gradient boosting can improve the accuracy of decision trees, but at the expense of the interpretability of the generated model. Additive models, such as those produced by gradient boosting, and full interaction models, such as CART, have been investigated largely in isolation. We show that these models exist along a spectrum, revealing previously unseen connections between these approaches. This paper introduces a rigorous formalization for the additive tree, an empirically validated learning technique for creating a single decision tree, and shows that this method can produce models equivalent to CART or gradient boosted stumps at the extremes by varying a single parameter. Although the additive tree is designed primarily to provide both the model interpretability and predictive performance needed for high-stakes applications like medicine, it also can produce decision trees represented by hybrid models between CART and boosted stumps that can outperform either of these approaches.

Prospective assessment of demographic characteristics associated with worse health related quality of life measures following definitive chemoradiation in patients with locally advanced non-small cell lung cancer.

BACKGROUND: The purpose of this study was to evaluate baseline demographic characteristics which may be associated with worse health related quality of life (HRQOL) for patients with locally advanced non-small cell lung cancer (NSCLC) receiving definitive chemoradiation (CRT). MATERIALS: Patients with NSCLC were prospectively enrolled on an Institutional Review Board-approved clinical trial between 2009 and 2012. HRQOL assessments were collected pre-radiation therapy (RT), during RT, and within 3 months post-RT using Euroqol (EQ-5D), MD Anderson Symptom Inventory (MDASI), and Functional Assessment of Cancer Therapy General (FACT-G). HRQOL correlation was assessed with categorical variables by Wilcoxon rank sum tests and with continuous variables by Pearson correlation. P<0.05 was defined as statistically significant. RESULTS: Forty-three consecutive patients received definitive concurrent CRT and completed assessments at one or more time-points. Patients most commonly had stage IIIB disease (72%), were married or with a partner (70%) and Caucasian (91%). Median patient age was 65 (range: 39-79) years and Charlson comorbidity index (CCI) was 0 (range: 0-5). Female gender, African-American ethnicity, age, chemotherapy type, baseline hemoglobin, and CCI were associated with worse post-treatment HRQOL measures. CONCLUSIONS: We have identified novel characteristics associated with worse quality of life following definitive CRT for lung cancer. Patients at risk for worse post-treatment quality of life may benefit from earlier follow-up and greater supportive measures following treatment.

The Use of Radiation Therapy for the Treatment of Malignant Pleural Mesothelioma: Expert Opinion from the National Cancer Institute Thoracic Malignancy Steering Committee, International Association for the Study of Lung Cancer, and Mesothelioma Applied Research Foundation.

INTRODUCTION: Detailed guidelines regarding the use of radiation therapy for malignant pleural mesothelioma (MPM) are currently lacking because of the rarity of the disease, the wide spectrum of clinical presentations, and the paucity of high-level data on individual treatment approaches. METHODS: In March 2017, a multidisciplinary meeting of mesothelioma experts was cosponsored by the U.S. National Cancer Institute, International Association for the Study of Lung Cancer Research, and Mesothelioma Applied Research Foundation. Among the outcomes of this conference was the foundation of detailed, multidisciplinary consensus guidelines. RESULTS: Here we present consensus recommendations on the use of radiation therapy for MPM in three discrete scenarios: (1) hemithoracic radiation therapy to be used before or after extrapleural pneumonectomy; (2) hemithoracic radiation to be used as an adjuvant to lung-sparing procedures (i.e., without pneumonectomy); and (3) palliative radiation therapy for focal symptoms caused by the disease. We discuss appropriate simulation techniques, treatment volumes, dose fractionation regimens, and normal tissue constraints. We also assess the role of particle beam therapy, specifically, proton beam therapy, for MPM. CONCLUSION: The recommendations provided in this consensus statement should serve as important guidelines for developing future clinical trials of treatment approaches for MPM.

Downstream Effect of a Proton Treatment Center on an Academic Medical Center.

PURPOSE: To quantify the effects of opening a proton center (PC) on an academic medical center (AMC)/radiation oncology department. METHODS AND MATERIALS: Radiation treatment volume and relative value units from fiscal year 2015 (FY15) to FY17 were retrospectively analyzed at the AMC and 2 community-based centers. To quantify new patient referrals to the AMC, we reviewed the electronic medical record for all patients seen at the PC since consults were initiated in November 2015 (n = 1173). Patients were excluded if the date of entry into the AMC electronic medical record predated their PC consultation. Hospital resource use and professional and technical charges were obtained for these patients. Academic growth, philanthropy, and resident education were evaluated based on grant submissions, clinical trial enrollment, philanthropy, and pediatric case exposure, respectively, from PC opening through FY17. RESULTS: From FY15 to FY17, radiation fractions at the AMC and the 2 community sites decreased by 14% (95% confidence interval [CI], 12%-16%, P < .001) and increased by 19% (95% CI, 16%-23%, P < .001) and 2% (95% CI, -1.1 to 4.3%, P = NS), respectively; the number of new starts decreased by 3% (95% CI, -13% to 7%, P = NS) and 2% (95% CI, -20% to 16%, P = NS) and increased by 13% (95% CI -2% to 27%, P = NS), respectively. At the AMC, technical and professional relative value units decreased by 5% and 14%, respectively. The PC made 561 external referrals to the AMC, which resulted in $2.38 million technical and $2.13 million professional charges at the AMC. Fifteen grant submissions ($12.83 million) resulted in 6 awards ($3.26 million). Twenty-two clinical trials involving proton therapy were opened, on which a total of 5% (n = 54) of patients enrolled during calendar years 2017 and 2018. The PC was involved in gift donations of $1.6 million. There was a nonsignificant 37% increase in number of pediatric cases. CONCLUSIONS: Despite a slight decline in AMC photon patient volumes and relative value units, a positive downstream effect was associated with the addition of a PC, which benefited the AMC.

Racial and Insurance-related Disparities in Delivery of Immunotherapy-type Compounds in the United States.

Racial and/or socioeconomic factors affect the type of therapies delivered for non-small cell lung cancer (NSCLC). Given the rapid expansion of immunotherapy for NSCLC, it is a crucial public health priority to evaluate disparities in administration thereof. The National Cancer Database (NCDB) was queried for newly diagnosed metastatic NSCLC. Patients were dichotomized based on receipt of immunotherapy-type compounds (ICs) based on NCDB coding. Multivariable logistic regression ascertained factors associated with IC delivery. Subgroup analysis, performed by univariate logistic regression modeling, evaluated the effect of race while stratifying for insurance type. Of 504,447 patients, 11,420 (2.3%) received ICs, and 493,027 (97.7%) did not. From 2004 to 2012, ≤1% of patients received ICs; however, 4.9% did so in 2013, 6.6% in 2014, and 8.7% in 2015. ICs were more likely administered to younger and healthier patients, those living farther from treating facilities, and in more educated areas (P<0.05 for all). ICs were more often delivered to adenocarcinomas, and patients who received chemotherapy but not radiotherapy (P<0.05 for all). In addition to geographic differences, uninsured and Medicaid populations received ICs less often, along with African Americans. On subgroup analysis, African Americans were less likely to receive ICs even when stratified for Medicare, Medicaid, or private insurances. Because IC utilization is expected to amplify even further going forward, these public health and economic issues are essential to identify and address appropriately, and have implications on pharmaceutical/insurance companies, value-based oncology, and public health policy. Methods to address these inequalities are also discussed.

A systematic review of the cost and cost-effectiveness studies of immune checkpoint inhibitors.

BACKGROUND: Escalating healthcare costs are necessitating the practice of value-based oncology. It is crucial to critically evaluate the economic impact of influential but expensive therapies such as immune checkpoint inhibitors (ICIs). To date, no systematic assessment of the cost-effectiveness (CE) of ICIs has been performed. METHODS: PRISMA-guided systematic searches of the PubMed database were conducted. Studies of head/neck (n = 3), lung (n = 5), genitourinary (n = 4), and melanoma (n = 8) malignancies treated with ICIs were evaluated. The reference willingness-to-pay (WTP) threshold was $100,000/QALY. RESULTS: Nivolumab was not cost-effective over chemotherapy for recurrent/metastatic head/neck cancers (HNCs). For non-small cell lung cancer (NSCLC), nivolumab was not cost-effective for a general cohort, but increased PD-L1 cutoffs resulted in CE. Pembrolizumab was cost-effective for both previously treated and newly-diagnosed metastatic NSCLC. For genitourinary cancers (GUCs, renal cell and bladder cancers), nivolumab and pembrolizumab were not cost-effective options. Regarding metastatic/unresected melanoma, ipilimumab monotherapy is less cost-effective than nivolumab, nivolumab/ipilimumab, and pembrolizumab. The addition of ipilimumab to nivolumab monotherapy was not adequately cost-effective. Pembrolizumab or nivolumab monotherapy offered comparable CE profiles. CONCLUSIONS: With limited data and from the reference WTP, nivolumab was not cost-effective for HNCs. Pembrolizumab was cost-effective for NSCLC; although not the case for nivolumab, applying PD-L1 cutoffs resulted in adequate CE. Most data for nivolumab and pembrolizumab in GUCs did not point towards adequate CE. Contrary to ipilimumab, either nivolumab or pembrolizumab is cost-effective for melanoma. Despite these conclusions, it cannot be overstated that careful patient selection is critical for CE. Future publication of CE investigations and clinical trials (along with longer follow-up of existing data) could substantially alter conclusions from this analysis.

Circulating Tumor Cell Assessment in Presumed Early Stage Non-Small Cell Lung Cancer Patients Treated with Stereotactic Body Radiation Therapy: A Prospective Pilot Study.

PURPOSE: In patients treated with stereotactic body radiation therapy (SBRT) for presumed early stage non-small cell lung cancer (NSCLC), detection and monitoring of circulating tumor cells (CTCs) may be useful for assessing treatment response safely and noninvasively. No published reports of CTC trends in this patient population exist to date. METHODS AND MATERIALS: Patients with clinically diagnosed stage I NSCLC treated with SBRT were eligible for this institutional review board-approved prospective clinical trial. Peripheral blood samples were assayed for CTCs via a green fluorescent protein-expressing adenoviral probe. CTC positivity was defined as 1.3 green fluorescent protein-positive cells/mL of collected blood. Samples were obtained before (pre-radiation therapy [RT]), during, and after SBRT (post-RT; months 1, 3, 6, 12, 18, and 24). SBRT was delivered in ≤5 fractions (median dose of 50 Gy in 12.5 Gy fractions) to a biological equivalent dose of ≥100 Gy in all cases. RESULTS: Forty-eight consecutive patients (T1a [73%], T1b [21%], and T2a [6%]) were enrolled. Median follow-up was 14.2 months. Twenty patients (42%) had a positive CTC level pre-RT, with a median CTC count of 4.2 CTCs per mL (interquartile range [IQR], 2.2-18.7). Of these 20 patients, 17 had evaluable post-RT CTC evaluations showing reduced CTC counts at 1 month (median, 0.2; IQR, 0.1-0.8) and 3 months (median, 0.6; IQR, 0-1.1). Three of these 17 patients experienced disease progression at a median of 19.9 months; all 3 experienced ≥1 positive post-RT CTC test predating clinical progression by a median of 16 months (range, 2-17 months). In contrast, among patients presenting with CTC-detectable disease and for whom all post-RT CTC tests were negative, none experienced recurrence or progression. CONCLUSIONS: CTC monitoring after SBRT for presumed early stage NSCLC may give lead-time notice of disease recurrence or progression. Conversely, negative CTC counts after treatment may provide reassurance of disease control. CTC analysis is thus potentially useful in enhancing clinical diagnosis and follow-up in this population.

Validation and clinical implementation of an accurate Monte Carlo code for pencil beam scanning proton therapy.

Monte Carlo (MC)-based dose calculations are generally superior to analytical dose calculations (ADC) in modeling the dose distribution for proton pencil beam scanning (PBS) treatments. The purpose of this paper is to present a methodology for commissioning and validating an accurate MC code for PBS utilizing a parameterized source model, including an implementation of a range shifter, that can independently check the ADC in commercial treatment planning system (TPS) and fast Monte Carlo dose calculation in opensource platform (MCsquare). The source model parameters (including beam size, angular divergence and energy spread) and protons per MU were extracted and tuned at the nozzle exit by comparing Tool for Particle Simulation (TOPAS) simulations with a series of commissioning measurements using scintillation screen/CCD camera detector and ionization chambers. The range shifter was simulated as an independent object with geometric and material information. The MC calculation platform was validated through comprehensive measurements of single spots, field size factors (FSF) and three-dimensional dose distributions of spread-out Bragg peaks (SOBPs), both without and with the range shifter. Differences in field size factors and absolute output at various depths of SOBPs between measurement and simulation were within 2.2%, with and without a range shifter, indicating an accurate source model. TOPAS was also validated against anthropomorphic lung phantom measurements. Comparison of dose distributions and DVHs for representative liver and lung cases between independent MC and analytical dose calculations from a commercial TPS further highlights the limitations of the ADC in situations of highly heterogeneous geometries. The fast MC platform has been implemented within our clinical practice to provide additional independent dose validation/QA of the commercial ADC for patient plans. Using the independent MC, we can more efficiently commission ADC by reducing the amount of measured data required for low dose "halo" modeling, especially when a range shifter is employed.

Association Between Treatment at High-Volume Facilities and Improved Overall Survival in Soft Tissue Sarcomas.

PURPOSE: Soft tissue sarcomas (STS) are rare malignancies that require complex multidisciplinary management. Therefore, facilities with high sarcoma case volume may demonstrate superior outcomes. We hypothesized that STS treatment at high-volume (HV) facilities would be associated with improved overall survival (OS). METHODS AND MATERIALS: Patients aged ≥18 years with nonmetastatic STS treated with surgery and radiation therapy at a single facility from 2004 through 2013 were identified from the National Cancer Database. Facilities were dichotomized into HV and low-volume (LV) cohorts based on total case volume over the study period. OS was assessed using multivariable Cox regression with propensity score-matching. Patterns of care were assessed using multivariable logistic regression analysis. RESULTS: Of 9025 total patients, 1578 (17%) and 7447 (83%) were treated at HV and LV facilities, respectively. On multivariable analysis, high educational attainment, larger tumor size, higher grade, and negative surgical margins were statistically significantly associated with treatment at HV facilities; conversely, black race and non-metropolitan residence were negative predictors of treatment at HV facilities. On propensity score-matched multivariable analysis, treatment at HV facilities versus LV facilities was associated with improved OS (hazard ratio, 0.87, 95% confidence interval, 0.80-0.95; P = .001). Older age, lack of insurance, greater comorbidity, larger tumor size, higher tumor grade, and positive surgical margins were associated with statistically significantly worse OS. CONCLUSIONS: In this observational cohort study using the National Cancer Database, receipt of surgery and radiation therapy at HV facilities was associated with improved OS in patients with STS. Potential sociodemographic disparities limit access to care at HV facilities for certain populations. Our findings highlight the importance of receipt of care at HV facilities for patients with STS and warrant further study into improving access to care at HV facilities.

Addition of Definitive Radiotherapy to Chemotherapy in Patients With Newly Diagnosed Metastatic Nasopharyngeal Cancer.

Background: Management of metastatic (M1) nasopharyngeal cancer (NPC) is controversial; data suggest high overall survival (OS) rates with definitive chemoradiotherapy (CRT). Herein, we evaluated OS in patients with M1 NPC undergoing chemotherapy alone versus CRT. Methods: The National Cancer Data Base was queried for M1 NPC cases. Patients undergoing no/unknown chemotherapy and/or with unknown/nondefinitive radiotherapy (RT) doses (<60 Gy) were excluded. Logistic regression analysis ascertained clinical factors associated with RT administration. Kaplan-Meier analysis evaluated OS between both cohorts; Cox proportional hazards modeling assessed factors associated with OS. Survival was then evaluated between matched populations using inverse-probability-weighted regression adjustment. OS between groups was also measured in patients surviving ≥1 and ≥3 years to address bias from poor-prognostic subsets (eg, widely disseminated disease), and those receiving CRT ≤30 and ≤60 days of each other (surrogates for concurrent CRT) versus >30 and >60 days (sequential) of each other. Results: Of 555 patients, 296 (53%) received chemotherapy alone and 259 (47%) underwent CRT. Patients undergoing CRT more often had private insurance (P=.001) and lived in areas with higher education levels (P=.028). Median OS in the chemotherapy-only and CRT cohorts were 13.7 and 25.8 months, respectively (P<.001); differences persisted between matched populations (P<.001). On multivariate analysis, receipt of additional RT independently predicted for improved OS (P<.001). OS differences between cohorts remained apparent when evaluating patients surviving for ≥1 (P<.001) and ≥3 (P=.002) years. Patients who received concurrent or sequential CRT displayed improved OS over those receiving chemotherapy alone, for both the 30-day (P<.001) and 60-day cutoffs (P<.001). Conclusions: Patients with M1 NPC undergoing definitive RT and chemotherapy experienced higher survival than those receiving chemotherapy alone. Risk stratification and patient selection for such combined modality interventions is critical.