Correlation Among Neighborhood-level Measures of the Tobacco Retail Environment.

INTRODUCTION: Tobacco retailer density and distance to tobacco retailers are understood to influence tobacco-related behaviors; however, there is no general agreement on how to best characterize or measure the tobacco retail environment (TRE). In this data-driven analysis, we examine similarities among neighborhood-level measures of the TRE and assess how geographic resolution of the neighborhood units may affect them. METHODS: We used locations of likely tobacco retailers in the United States (US) to calculate multiple retailer count, density, and distance measures. Measures were calculated at the Census block group, tract, and county (including county equivalents) levels of geographic aggregation. Spearman's correlation was used to evaluate similarity among the TRE measures. RESULTS: At the block group and tract level, correlation among all TRE measures ranged from slightly negative (ρ = -0.03) to nearly perfect (ρ = 0.99). At both levels of aggregation, distance-based TRE measures were highly correlated (ρ > 0.76). At the block group level, simple count of retailers was highly correlated with the density measures (ρ > 0.83), and at the tract level, simple count was moderately to highly correlated with the density measures (ρ > 0.5). Findings were generally similar at the county level; a notable deviation was that retailers per person was negatively correlated with all other TRE measures (range from ρ = -0.08 to ρ = -0.32). CONCLUSIONS: Some common measures were not correlated, suggesting they capture different aspects of the TRE; similarity among the various measures also varied by level of geographic aggregation. IMPLICATIONS: Because the tobacco retail environment shapes people's tobacco-related behaviors, using appropriate measures to characterize it at a neighborhood-level is paramount. Our work highlights both the similarities and differences among a set of common measures, thereby suggesting the measures may be capturing different aspects of the overall retail environment. Our findings regarding geographic level of aggregation underscore the importance of neighborhood definition in any tobacco retail environment analysis.

The Use of Sentinel Lymph Node Biopsy in Patients Undergoing Mastectomy for DCIS.

BACKGROUND: Current guidelines do not recommend routine sentinel node biopsy (SLNB) for ductal carcinoma in situ (DCIS), except in the setting of mastectomy or microinvasive disease. This study aimed to evaluate national SLNB utilization in women undergoing upfront mastectomy for DCIS, identify predictors of SLNB utilization, and determine the percentage with a positive SLNB. METHODS: A retrospective cohort analysis was performed using the NCDB of women with clinical DCIS who underwent upfront mastectomy between 2012 and 2017. Demographic and clinicopathologic variables were compared between patients who underwent SLNB and those who did not. Multivariate logistic regression models were used to identify factors associated with SLNB utilization and positive SLNB. RESULTS: About 38,973 patients met inclusion criteria: 34,231 (88%) underwent SLNB and 4742 (12%) had no surgical axillary staging. Most patients were age 50-69 (51%), non-Hispanic White (71%), with private insurance (66%). On multivariate analysis, older patients were less likely to receive SLNB (P < .01), while patients with higher grade DCIS were more likely to undergo SLNB (P < .01). In those who underwent SLNB (n = 34,231), only 1,149 (3.4%) had nodal involvement. Non-Hispanic Black patients had increased odds of a positive SLNB (P < .01), while those with estrogen receptor positive disease were less likely to be node positive (OR 0.68, P < .001). CONCLUSIONS: While 88% of patients had a SLNB, only 3.4% were found to be node positive. Given this low rate, it is reasonable to consider SLNB omission in select patients with low grade, hormone receptor positive DCIS undergoing upfront mastectomy.

Supply and demand effects between tobacco retailer density and smoking prevalence.

OBJECTIVE: Places with more tobacco retailers have higher smoking prevalence levels, but whether this is because retailers locate where people who smoke live or whether tobacco availability prompts tobacco use is unknown. In this study, we compare the role of consumer demand with that of tobacco supply in longitudinal, area-based associations of tobacco retailer density with smoking prevalence. METHODS: We merged annual adult smoking prevalence estimates derived from the USA Behavioural Risk Factor Surveillance System data with annual county estimates of tobacco retailer density calculated from the National Establishment Time Series data for 3080 counties between 2000 and 2010. We analysed relationships between retailer density and smoking in 3080 counties, using random intercept cross-lagged panel models and employing two measures of tobacco retailer density capturing the number of likely tobacco retailers in a county divided by either the population or land area. RESULTS: Both density models provided evidence of significant demand and supply effects; in the population-based model, the association of smoking prevalence in 1 year with tobacco retailer density in the next year (standardised coefficient=0.038, p<0.01) was about double the association between tobacco retailer density with subsequent smoking prevalence (0.017, p<0.01). The reverse was true in the land area-based model, where the supply effect (0.042, p<0.01) was more than 10 times stronger than the demand effect (0.003, p<0.01). CONCLUSIONS: Policies that restrict access to retail tobacco have the potential to reduce smoking prevalence, but pairing such policies with interventions to reduce consumer demand remains important.

In-silico identification of deleterious non-synonymous SNPs of TBX1 gene: Functional and structural impact towards 22q11.2DS.

The TBX1 gene plays a critical role in the development of 22q11.2 deletion syndrome (22q11.2DS), a complex genetic disorder associated with various phenotypic manifestations. In this study, we performed in-silico analysis to identify potentially deleterious non-synonymous single nucleotide polymorphisms (nsSNPs) within the TBX1 gene and evaluate their functional and structural impact on 22q11.2DS. A comprehensive analysis pipeline involving multiple computational tools was employed to predict the pathogenicity of nsSNPs. This study assessed protein stability and explored potential alterations in protein-protein interactions. The results revealed the rs751339103(C>A), rs780800634(G>A), rs1936727304(T>C), rs1223320618(G>A), rs1248532217(T>C), rs1294927055 (C>T), rs1331240435 (A>G, rs1601289406 (A>C), rs1936726164 (G>A), and rs911796187(G>A) with a high-risk potential for affecting protein function and stability. These nsSNPs were further analyzed for their impact on post-translational modifications and structural characteristics, indicating their potential disruption of molecular pathways associated with TBX1 and its interacting partners. These findings provide a foundation for further experimental studies and elucidation of potential therapeutic targets and personalized treatment approaches for individuals affected by 22q11.2DS.

Neighbourhood inequities in the availability of retailers selling tobacco products: a systematic review.

OBJECTIVE: To examine inequities in tobacco retailer availability by neighbourhood-level socioeconomic, racial/ethnic and same-sex couple composition. DATA SOURCES: We conducted a 10 November 2022 search of PubMed, PsycINFO, Global Health, LILACS, Embase, ABI/Inform, CINAHL, Business Source Complete, Web of Science and Scopus. STUDY SELECTION: We included records from Organisation for Economic Co-operation and Development member countries that tested associations of area-level measures of tobacco retailer availability and neighbourhood-level sociodemographic characteristics. Two coders reviewed the full text of eligible records (n=58), including 41 records and 205 effect sizes for synthesis. DATA EXTRACTION: We used dual independent screening of titles, abstracts and full texts. One author abstracted and a second author confirmed the study design, location, unit of analysis, sample size, retailer data source, availability measure, statistical approach, sociodemographic characteristic and unadjusted effect sizes. DATA SYNTHESIS: Of the 124 effect sizes related to socioeconomic inequities (60.5% of all effect sizes), 101 (81.5%) indicated evidence of inequities. Of 205 effect sizes, 69 (33.7%) tested associations between retailer availability and neighbourhood composition of racially and ethnically minoritised people, and 57/69 (82.6%) documented inequities. Tobacco availability was greater in neighbourhoods with more Black, Hispanic/Latine and Asian residents (82.8%, 90.3% and 40.0% of effect sizes, respectively). Two effect sizes found greater availability with more same-sex households. CONCLUSIONS: There are stark inequities in tobacco retailer availability. Moving beyond documenting inequities to partnering with communities to design, implement, and evaluate interventions that reduce and eliminate inequities in retail availability is needed to promote an equitable retail environment. PROSPERO REGISTRATION NUMBER: CRD42019124984.

Retailers' Compliance with Federal Age of Cigarette Sales Policies -- Pitt County, North Carolina, January-March 2022.

BACKGROUND: Tobacco use remains a leading cause of preventable morbidity and premature mortality. In December 2019, the federal age of sale for tobacco products increased from 18 to 21 years of age. This study aimed to evaluate the implementation of federal tobacco 21 policies in Pitt County, North Carolina (NC), by conducting multiple purchase attempts for cigarettes. METHOD: Stores in Pitt County that sold cigarettes were randomly sampled and visited by up to six different underage (18-20) buyers who attempted to buy cigarettes from January-March 2022. Buyers made a total of 217 cigarette purchase attempts from 49 Pitt County retailers. Analyses were conducted using SPSS Complex Samples (v.28/Macintosh) and estimate retailer prevalence of requesting identification (ID) and selling to underage buyers across multiple purchase attempts. RESULTS: On average, retailers failed to request ID in 15.4% of purchase attempts (95% CI: 9.4%-21.3%) and sold to an underage buyer 34.2% of the time (95% CI: 27.0-41.4%). Additionally, 75.5% (95% CI: 63.4%-84.6%) of retailers sold to an underage buyer at least once. LIMITATIONS: This study is limited to a single county in NC and to underage buyers aged 18 to 20. CONCLUSION: There is widespread non-compliance with federal age of sale policies for tobacco products in Pitt County, NC. State enforcement is warranted, and NC's youth access law should be amended to match the federal age of sale. Changes to the law should allow research involving underage purchases.

Divergent Cellular Expression Patterns of PD-L1 and PD-L2 Proteins in Breast Cancer.

PD-L1 immunohistochemistry (IHC) has become an established method for predicting cancer response to targeted anti-PD1 immunotherapies, including breast cancer (BC). The alternative PD-1 ligand, PD-L2, remains understudied but may be a complementary predictive marker. Prospective analysis of 32 breast cancers revealed divergent expression patterns of PD-L1 and PD-L2. PD-L1-positivity was higher in immune cells than in cancer cells (median = 5.0% vs. 0.0%; p = 0.001), whereas PD-L2-positivity was higher in cancer cells than immune cells (median = 30% vs. 5.0%; p = 0.001). Percent positivity of PD-L1 and PD-L2 were not correlated, neither in cancer cells nor immune cells. Based on a cut-point of ≥1% positivity, ER+ tumors (n = 23) were frequently PD-L2-positive (73.9%), whereas only 40.9% were PD-L1-positive. These data suggest differential control of cellular PD-L1 and PD-L2 expression in BC and a potential role for PD-L2 IHC as a complementary marker to PD-L1 to improve selection of aggressive ER+ BC that may benefit from anti-PD-1 therapy.

Comparison of Tobacco Product Prices at Fort Liberty Army Installation and Surrounding Community Areas, 2021.

INTRODUCTION: High rates of tobacco use persist in the U.S. military, with 18.4% of service members smoking cigarettes in 2018. The Department of Defense's (DoD) 2017 policy required that tobacco retailers on military installations set tobacco product prices equal to the most common community price, including tax, but there is limited evidence confirming whether local retailers are adhering to this policy. We examined tobacco product pricing in tobacco retailers on- and off-post at the largest U.S. Army installation, Fort Liberty, and Cumberland County, North Carolina. METHODS: Between June-August 2021, we collected data on tobacco product availability, price, and promotions from retailers on Fort Liberty (n=14) and a random sample of off-post retailers within 10-miles of installation gates (n=52). We calculated the mode, mean, and median price of each product, plus the difference in these prices at on- and off-post retailers. We used Welch's t-test to test differences in mean prices between on- vs. off-post retailers. RESULTS: The mode, mean, and median prices of cigarette packs and cartons were lower on-post than off-post (e.g., $0.51-$0.55 cheaper for Marlboro cigarette packs on-post). However, the mode, mean, and median prices of smokeless tobacco products and little cigars were higher on-post than off-post (e.g., $0.82-$0.89 more costly for Swisher Sweets 2-packs on-post). CONCLUSION: Results highlight the need for continued enforcement to ensure compliance with the 2017 DoD policy. Comprehensive policy action to reduce tobacco price disparities on- and off-post is critical to reducing high rates of tobacco use among service members. IMPLICATIONS: Despite the implementation of the 2017 DoD pricing policy, some tobacco products remain cheaper at tobacco retailers on-post compared to off-post retailers. Our results highlight the need for greater routine surveillance to increase implementation of the policy-particularly for cigarettes-to reduce high rates of tobacco use among service members.

Neighborhood Inequities in Tobacco Product Descriptors, Washington, DC, 2018-2019.

BACKGROUND: The tobacco industry uses product descriptors to communicate reduced harm and increase appeal. This cross-sectional study assessed store-level racial, ethnic, and socioeconomic inequities in the distribution of retail tobacco product descriptors in a convenience sample of retailers in Washington, DC. METHODS: Young adults (n = 146) who did not currently use tobacco reported real-time store visits over 14 days. Trained data collectors took high-resolution photographs of all tobacco (including e-cigarette) marketing in each store (n = 96) participants visited. We coded text descriptors on tobacco product advertisements and displays into descriptor categories (eg, fruit, sweet, concept). We fit multilevel models to examine relationships between store neighborhood census tract-level racial, ethnic, and socioeconomic characteristics and tobacco product descriptors in stores. As a supplementary analysis, we used geospatial methods to model predicted patterns of descriptors at the census tract level. RESULTS: Stores located in census tracts with the highest versus lowest percentage of Black residents had a greater count of fruit, sweet or dessert, alcohol, and concept descriptors (p < .05), similar to findings from the geospatial approach. Adjusted models also indicated some inequities in stores in census tracts with higher percentages of Hispanic or Latino residents for fruit, alcohol, and concept descriptors; however, tract-level models showed opposite results for concept flavors. CONCLUSIONS: In this convenience sample, fruit, alcohol, sweet/dessert, and concept FTP descriptors were prevalent in stores in neighborhoods with more Black residents demonstrated through two analytic approaches. Surveillance using representative samples of tobacco retailers could improve the ability to track the extent of this inequity. IMPLICATIONS: We document inequities in the amount of fruit, sweet or dessert, alcohol, and concept flavor descriptors in stores across neighborhoods in Washington, DC. Federal, state, and local regulatory action is needed to reduce inequities in flavored tobacco product availability and marketing, including for concept flavors.

Risk Factors for Skin Flap and Nipple-Areolar Necrosis in Patients Undergoing Nipple-Sparing Mastectomy With Deep Inferior Epigastric Perforator Flap Reconstruction.

INTRODUCTION: Nipple-sparing mastectomy (NSM) with deep inferior epigastric perforator (DIEP) flap reconstruction is a surgical option for select patients with or at risk of breast cancer. However, post-operative skin flap and nipple-areolar complex (NAC) necrosis remain common complications. This study aimed to identify factors associated with necrosis in patients undergoing NSM with DIEP reconstruction. METHODS: A retrospective cohort study was performed from 2015 to 2023. 74 variables were analyzed in patients undergoing NSM with DIEP. Patients were stratified into 3 groups based on post-operative skin/NAC necrosis: none, partial thickness, and full thickness. Comparative and descriptive statistics were performed via t-tests, ANOVA, and chi-squared tests. RESULTS: 34 women with 31 breast cancers met inclusion. 44% experienced necrosis: 15% partial thickness and 29% full thickness. The majority were white (85.3%) with mean age of 50 years (SD = 9.11). In patients with immediate DIEP reconstruction, hypoperfused areas identified by SPY angiography increased risk of necrosis (P = .012). Approximately 50% of both partial thickness and full thickness necrosis patients had concerns on SPY angiography. Former smokers in the full thickness necrosis group had more pack years than those without necrosis (9 vs .65 pack years, P = .035). CONCLUSION: In patients receiving NSM with DIEP flap reconstruction, those with hypoperfusion on SPY angiography and longer smoking history had higher necrosis rates. This supports the continued used of SPY angiography and the role of pre-operative counseling in former smokers with increased pack years on their risk of necrosis and the role of preventative measures in the perioperative setting.

Geographical differences in the financial impacts of different forms of tobacco licence fees on small retailers in Scotland.

OBJECTIVE: Retailer licencing fees are a promising avenue to regulate tobacco availability. However, they face strong opposition from retailers and the tobacco industry, who argue significant financial impacts. This study compares the impacts of different forms of tobacco licence schemes on retailers' profits in Scotland. METHODS: We calculated gross profits from tobacco sales in 179 convenience stores across Scotland using 1 099 697 electronic point-of-sale records from 16 weeks between 2019 and 2022. We estimated different fees using universal, volumetric and separate urban/rural schemes. We identified the point at which 50% of retailers would no longer make a gross profit on tobacco sales for each scheme and modelled the financial impact of 10 incremental fee levels. The financial impact was assessed based on changes in retailers' tobacco gross profits. Differences by neighbourhood deprivation and urban/rural status were examined. RESULTS: The gross profit from tobacco per convenience store averaged £15 859/year. Profits were 2.29 times higher in urban (vs rural) areas and 1.59 times higher in high-deprivation (vs low-deprivation) areas, attributable to higher sales volumes. Tobacco gross profit decreased proportionally with increasing fee levels. Universal and urban/rural fees had greater gross profit reductions in rural and/or less deprived areas, where profits were lower, compared with volumetric fees. CONCLUSION: The introduction of tobacco licence fees offers a potential opportunity for reducing the availability of tobacco retailers. The likely impact of a tobacco licence fee is sensitive to the type of licence scheme implemented, the level at which fees are set and the retailers' location in relation to neighbourhood deprivation and rurality.

Does Neoadjuvant Chemotherapy in Clinical T1-T2 N0 Triple-Negative Breast Cancer Increase the Extent of Axillary Surgery?

BACKGROUND: Current management strategies for early-stage triple-negative breast cancer (TNBC) include upfront surgery to determine pathologic stage to guide chemotherapy recommendations, or neoadjuvant chemotherapy (NAC) to de-escalate surgery, elucidate tumor response, and determine the role of adjuvant chemotherapy. However, patients who receive NAC with residual pathological nodal (pN) involvement require axillary lymph node dissection (ALND) as they are Z11/AMAROS ineligible. We aimed to evaluate the impact of NAC compared with upfront surgery on pN status and ALND rates in cT1-2N0 TNBC. METHODS: The National Cancer Database (NCDB) was queried for women with operable cT1-2N0 TNBC from 2014 to 2019. Demographic, clinicopathologic, and treatment data were collected. Multivariable linear regression analysis was performed to assess the odds of pN+ disease and undergoing ALND. RESULTS: Overall, 55,624 women were included: 26.9% (n = 14,942) underwent NAC and 73.1% (n = 40,682) underwent upfront surgery. The NAC cohort was younger (mean age 52.9 vs. 61.3 years; p < 0.001) with more cT2 tumors (71.6% vs. 31.0%; p < 0.001), and had lower ALND rates (4.3% vs. 5.5%; p < 0.001). The upfront surgery cohort was more likely to have one to three pathologically positive nodes (12.1% vs. 6.5%; odds ratio [OR] 2.37, 95% confidence interval (CI) 2.17-2.58; p < 0.001) but there was no difference in the likelihood of ALND (OR 1.1, 95% CI 0.99-1.24; p = 0.08). CONCLUSION: Patients who underwent upfront surgery were more likely to be pN+; however, ALND rates were similar between the two cohorts. Thus, the use of NAC does not result in a higher odds of ALND and the decision for NAC should be individualized and based on modern guidelines and systemic therapy benefits.

National trends in neoadjuvant chemotherapy utilization in patients with early-stage node-negative triple-negative breast cancer: the impact of the CREATE-X trial.

PURPOSE: Neoadjuvant chemotherapy (NAC) for triple-negative breast cancer (TNBC) allows for assessment of tumor pathological response and has survival implications. In 2017, the CREATE-X trial demonstrated survival benefit with adjuvant capecitabine in patients TNBC and residual disease after NAC. We aimed to assess national rates of NAC for cT1-2N0M0 TNBC before and after CREATE-X and examine factors associated with receiving NAC vs adjuvant chemotherapy (AC). METHODS: A retrospective cohort study of women with cT1-2N0M0 TNBC diagnosed from 2014 to 2019 in the National Cancer Database (NCDB) was performed. Variables were analyzed via ANOVA, Chi-squared, Fisher Exact tests, and a multivariate linear regression model was created. RESULTS: 55,633 women were included: 26.9% received NAC, 52.4% AC, and 20.7% received no chemotherapy (median ages 53, 59, and 71 years, p < 0.01). NAC utilization significantly increased over time: 19.5% in 2014-15 (n = 3,465 of 17,777), 27.1% in 2016-17 (n = 5,140 of 18,985), and 33.6% in 2018-19 (n = 6,337 of 18,871, p < 0.001). On multivariate analysis, increased NAC was associated with younger age (< 50), non-Hispanic white race/ethnicity, lack of comorbidities, cT2 tumors, care at an academic or integrated-network cancer program, and diagnosis post-2017 (p < 0.05 for all). Patients with government-provided insurance were less likely to receive NAC (p < 0.01). Women who traveled > 60 miles for treatment were more likely to receive NAC (p < 0.01). CONCLUSION: From 2014 to 2019, NAC utilization increased for patients with cT1-2N0M0 TNBC. Racial, socioeconomic, and access disparities were observed in who received NAC vs AC and warrants interventions to ensure equitable care.

"If You Just Tell Me You're 18, I'll Still Sell to You": A Qualitative Study of Underage Tobacco Product Purchasing Experiences in a Tobacco 21 Compliance Study.

BACKGROUND: Tens of thousands of underage tobacco buy attempts are conducted each year for research, compliance, and public health surveillance. However, little research has qualitatively examined the perceptions and experiences of underage buyers participating in these programs. We sought to understand underage buyers' experiences and gather recommendations for protocol improvements. METHODS: We conducted semi-structured interviews in the fall of 2022 to assess experiences with underage tobacco product purchasing. Participants (N = 19, 58% male, 42% White) were research assistants aged 18-20 in New Jersey, New York, or North Carolina. Interviews examined purchasing experiences in relation to store characteristics, clerk interactions, and buyer identities. We used deductive and inductive thematic coding to explore key themes related to buyer experiences. RESULTS: We identified four themes: (1) non-chain stores lacked consistency in verifying age; (2) female data collectors experienced uncomfortable situations more frequently than male data collectors; (3) not identifying with the store's typical demographics impacted purchase attempts; and (4) participants suggested improvements for inspections and research during training. DISCUSSION: Retailer education, widespread adoption of ID scanners, and enforcement could increase standardization of ID requests and verification. Male and female buyers can be trained on what they might expect based on their gender, as well as how to maneuver through unwanted situations. Consideration of shared identity is important for future waves of data collection and research. Efforts to improve training include more extensive mock purchase training with supervisors well-versed in this area. IMPLICATIONS: Electronic ID verification and promoting compliance at non-chain retailers could impact access to tobacco products for underage buyers. Training for underage buyers in research and compliance assessments should focus on ways to enhance data collectors' confidence when making a purchase attempt, which may improve the validity of the rate of sales to individuals under 21.

Impact and Equity of New York City's Tobacco Retail Reduction Initiative.

INTRODUCTION: High levels of tobacco retailer density in communities is associated with a range of tobacco use behaviors and is a key structural driver of tobacco-related disparities. This study evaluates the impacts of New York City's (NYC) novel policy intervention to cap tobacco retail licenses on tobacco retailer density levels and neighborhood inequities in tobacco access. METHODS: Using geocoded tobacco retail licensing data from 2010 to 2022, Bayesian conditional autoregressive Poisson panel models estimated the association between policy implementation in 2018 and retailer density per 1,000 population, controlling for neighborhood-level sociodemographic factors. Data were analyzed in 2023. RESULTS: The number of tobacco retail licenses decreased from 9,304 in 2010 to 5,107 in 2022, with the rate of decline significantly accelerating post-policy (-14·2% versus -34·2%). Policy effects were stronger in districts with lower income and greater proportions of non-Hispanic Black residents. CONCLUSIONS: NYC's policy substantially reduced tobacco retailer density and appeared to close longstanding patterns of inequity in tobacco access, serving as a rare example of a tobacco control policy that may effectively reduce tobacco-related disparities. This emergent approach to restructure tobacco retail in communities may reach populations that have not benefitted from traditional tobacco control policies and should be considered by other localities.

Spatial Clustering of Tobacco Retailers Near US Public Schools.

INTRODUCTION: Previous studies have found that tobacco retailers cluster near schools. However, all retail outlets may be located near each other and near schools due to existing infrastructure and zoning policies. We assessed whether tobacco retailers cluster near schools in the United States more than expected when accounting for existing retail locations. AIMS AND METHODS: We identified 322 056 probable tobacco retailers, 95 110 public schools, and more than 3.8 million businesses comparable to tobacco retailers in land use and business type. We created 500 simulated tobacco retailer datasets by randomly selecting from the larger list of businesses. For each simulated dataset, we calculated the distance from schools to the nearest tobacco retailer (proximity) and the count of tobacco retailers within 800 m of schools (density). Observed proximity and density values were compared to 95% coverage intervals from the 500 simulations. We stratified analyses by urbanicity, percentage of students in the free and reduced-priced lunch program (FRLP), and percentage of Hispanic/Latino, non-Hispanic Black, and non-Hispanic white students. RESULTS: Tobacco retailers were closer to schools in rural areas, cities, and towns and more dense around schools in rural areas, cities, and suburbs compared to random locations in potential retail space. Schools with more students receiving FRLP had higher density than expected while schools with fewer students receiving FRLP had lower density than expected. Within rural areas, clustering did not vary across sociodemographic groups. Within non-rural areas, there were inequities in clustering by racial, ethnic, and socioeconomic school composition. CONCLUSIONS: Tobacco retailers cluster near schools after accounting for existing business patterns. There are inequities in clustering by sociodemographic school composition. IMPLICATIONS: This study provides compelling evidence that tobacco retailers cluster near US public schools and that there are racial, ethnic, and socioeconomic inequities in clustering, even when accounting for overall retail location patterns. Given that public schools tend to reflect neighborhood demographics, policies to limit tobacco retailers near schools may reduce both school-based and neighborhood-based inequities.