Addressing social needs in oncology care: another research-to-practice gap.

Social determinants of health and unmet social needs are directly related to cancer outcomes, from diagnosis to survivorship. If identified, unmet social needs can be addressed in oncology care by changing care plans in collaboration with patients' preferences and accounting for clinical practice guidelines (eg, reducing the frequency of appointments, switching treatment modalities) and connecting patients to resources within healthcare organizations (eg, social work support, patient navigation) and with community organizations (eg, food banks, housing assistance programs). Screening for social needs is the first step to identifying those who need additional support and is increasingly recognized as a necessary component of high-quality cancer care delivery. Despite evidence about the relationship between social needs and cancer outcomes and the abundance of screening tools, the implementation of social needs screening remains a challenge, and little is known regarding the adoption, reach, and sustainability of social needs screening in routine clinical practice. We present data on the adoption and implementation of social needs screening at two large academic cancer centers and discuss three challenges associated with implementing evidence-based social needs screening in clinical practice: (1) identifying an optimal approach for administering social needs screening in oncology care, (2) adequately addressing identified unmet needs with resources and support, and (3) coordinating social needs screening between oncology and primary care.

The unique risk factor profile of triple negative breast cancer: a comprehensive meta-analysis.

BACKGROUND: Triple-negative breast cancer (TNBC) has a poor prognosis compared to other breast cancer subtypes. This systematic review and meta-analysis examines whether known risk factors for breast cancer are also associated with TNBC in adult females. METHODS: EMBASE, Medline, SCOPUS, and grey literature were queried with no limit on the date or language of publication. The exposures of interest included parity, breastfeeding, duration of breastfeeding, age at menarche, age at first live birth, oral contraceptive (OC) use, duration of OC use, use of menopausal hormone therapy (MHT), family history, body mass index (BMI), alcohol use, smoking and breast density. The main outcome of interest was TNBC. Study quality was determined using the Newcastle-Ottawa scale for case control studies and cohort studies. We estimated weighted odds ratios from random effects models to study the exposure-outcome associations. Protocol was registered under the number: PROSPERO 2021 CRD42021254594. RESULTS: Thirty-three studies were included. Family history, longer duration of oral contraceptive use, and higher breast density were significantly associated with increased risk for TNBC, whereas, later age at menarche, later age at first birth and breastfeeding were protective against TNBC. Parity, MHT, alcohol, smoking, and BMI were not significantly associated with TNBC overall, but higher parity was associated with higher risk among Black women. CONCLUSION: Our findings highlight that TNBC has a distinct risk-factor profile compared to overall breast cancer. This can be the foundational work in identification of actionable TNBC risk factors to improve prevention and early detection of these poor prognosis breast tumors.

Five-Year Outcomes of a Phase 1/2 Trial of Accelerated Partial Breast Irradiation Using Proton Therapy for Women With Stage 0-IIA Breast Cancer.

Purpose: We report the results of a phase 1/2 trial of external beam partial breast radiation using proton therapy. Methods and Materials: Eligible patients included stage 0-IIA breast cancer pTis-T2, N0, and size ≤3 cm. Proton beam radiation was used to deliver 3.85 Gy twice daily to 38.5 Gy. The phase 1 portion determined feasibility based on criteria of successful plan creation, treatment delivery, and acute toxicity grade ≥3 in ≤20% of patients. The phase 2 portion had efficacy goals of acute toxicity grade ≥3 in ≤20% of patients and observing physician-rated cosmesis of excellent or good >85% of patients at 2 years. Results: From April 2013 to March 2015, there were 12 patients enrolled onto the phase 1 portion, and the preplanned analysis of feasibility was met in all 4 required criteria. From July 2015 through December 2019 there were 28 patients with 29 treated breasts (1 bilateral) enrolled onto the phase 2 portion of the trial out of 45 originally planned. The trial was closed to accrual because of the coronavirus pandemic and not reopened. Thirty-eight breasts were treated with double-scattering and 3 pencil-beam scanning protons. The median follow-up of the 40 patients is 5.4 years (range, 2.3-8.6 years). There was 1 local recurrence. There was no grade ≥3 acute or late toxicity. At baseline all patients had physician-rated cosmesis good or excellent but at 2 years was excellent in 56%, good in 19%, and fair in 25%. Conclusions: Proton-accelerated partial breast irradiation delivered with a twice-daily fractionation was feasible and associated with very low acute and long-term toxicity. However, the trial did not meet goals for cosmesis outcomes and was closed prematurely. Future study is needed to determine whether pencil-beam scanning protons or different fractionation could improve these outcomes.

Rates of price disclosure associated with the surgical treatment of early-stage breast cancer one year after implementation of federal regulations.

PURPOSE: Mastectomy, breast reconstruction (BR) and breast conserving therapy (BCT) are core components of the treatment paradigm for early-stage disease but are differentially associated with significant financial burdens. Given recent price transparency regulations, we sought to characterize rates of disclosure for breast cancer-related surgery, including mastectomy, BCT, and BR (oncoplastic reconstruction, implant, pedicled flap and free flap) and identify associated factors. METHODS: For this cross-sectional analysis, cost reports were obtained from the Turquoise Health price transparency platform for all U.S. hospitals meeting national accreditation standards for breast cancer care. The Healthcare Cost Report Information System was used to collect facility-specific data. Addresses were geocoded to identify hospital referral and census regions while data from CMS was also used to identify the geographic practice cost index. We leveraged a Poisson regression model and relevant Medicare billing codes to analyze factors associated with price disclosure and the availability of an OOP price estimator. RESULTS: Of 447 identified hospitals, 221 (49.4%) disclosed prices for mastectomy and 188 42.1%) disclosed prices for both mastectomy and some form of reconstruction including oncoplastic reduction (n = 184, 97.9%), implants (n = 187, 99.5%), pedicled flaps (n = 89, 47.3%), and free flaps (n = 81, 43.1%). Non-profit status and increased market competition were associated with price nondisclosure. 121 hospitals (27.1%) had an out-of-pocket price estimator that included at least one breast surgery. CONCLUSIONS: Most eligible hospitals did not disclose prices for breast cancer surgery. Distinct hospital characteristics were associated with price disclosure. Breast cancer patients face persistent difficulty in accessing costs.

At the Intersection of Intersectionality: Race and Gender Diversity Among Surgical Faculty and Trainees.

OBJECTIVE: To compare the representation of intersectional (ie, racial/ethnic and gender) identities among surgical faculty versus medical students. BACKGROUND: Health disparities are pervasive in medicine, but diverse physicians may help the medical profession achieve health equity. METHODS: Data from the Association of American Medical Colleges for 140 programs (2011/2012-2019/2020) were analyzed for students and full-time surgical faculty. Underrepresented in medicine (URiM) was defined as Black/African American, American Indian/Alaskan Native, Hispanic/Latino/Spanish Origin, or Native Hawaiian/Other Pacific Islander. Non-White included URiM plus Asian, multiracial, and non-citizen permanent residents. Linear regression was used to estimate the association of year and proportions of URiM and non-White female and male faculty with proportions of URiM and non-White students. RESULTS: Medical students were comprised of more White (25.2% vs 14.4%), non-White (18.8% vs 6.6%), and URiM (9.6% vs 2.8%) women and concomitantly fewer men across all groups versus faculty (all P < 0.01). Although the proportion of White and non-White female faculty increased over time (both P ≤ 0.001), there was no significant change among non-White URiM female faculty, nor among non-White male faculty, regardless of whether they were URiM or not. Having more URiM male faculty was associated with having more non-White female students (estimate = +14.5% students/100% increase in faculty, 95% CI: 1.0% to 8.1%, P = 0.04), and this association was especially pronounced for URiM female students (estimate = +46.6% students/100% increase in faculty, 95% CI: 36.9% to 56.3%, P < 0.001). CONCLUSIONS: URiM faculty representation has not improved despite a positive association between having more URiM male faculty and having more diverse students.

Racial disparities in selected micronutrient deficiencies after bariatric surgery: A systematic review.

BACKGROUND: Bariatric surgery has been associated with numerous micronutrient deficiencies. Several observational studies have found that these deficiencies are more common in racially/ethnically minoritized patients. OBJECTIVES: To conduct a systematic review to investigate whether racially/ethnically minoritized patients experience worse nutritional outcomes after bariatric surgery. SETTING: University of Wisconsin-Madison. METHODS: PubMed, CINAHL, PsychINFO, and Cochrane databases were queried. We searched for manuscripts that reported micronutrient levels or conditions related to micronutrient deficiencies according to race/ethnicity (White, African American/Black, and Hispanic) after laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass between 2002 and 2022. Eleven micronutrients (vitamins A, B1 [thiamine], B12, D, E, K, calcium, copper, folate, iron, and zinc), and four conditions (anemia, bone loss, fractures, and hyperparathyroidism) were assessed. RESULTS: Abstracts from 953 manuscripts were screened; 18 full-text manuscripts were reviewed for eligibility, and ten met the inclusion criteria. Compared to White patients, African Americans had a higher prevalence of thiamine, vitamin D, and vitamin A deficiencies. There were no differences in calcium and vitamin B12 deficiencies. The other six micronutrients were not assessed according to race/ethnicity. Hyperparathyroidism was more prevalent in African Americans than White patients in the three studies that evaluated it. The prevalence of fractures was mixed. Anemia and bone loss were not evaluated according to race/ethnicity. CONCLUSIONS: Although the literature on micronutrient outcomes following bariatric surgery according to race/ethnicity is limited, African Americans appear to experience a higher prevalence of vitamin deficiencies and associated conditions. Qualitative and quantitative research to explore these disparities is warranted.

Identifying and Addressing Barriers to Screening Mammography in a Medically Underserved Community.

RATIONALE AND OBJECTIVES: Breast cancer mortality is 40% higher for Black women compared to White women. This study seeks to assess knowledge of breast cancer screening recommendations and identify barriers to risk assessment and mammographic screening among a medically underserved, low-income, predominantly Black community in West Philadelphia. MATERIALS AND METHODS: During a free mobile mammography screening event, women were offered surveys to assess perceptions of and barriers to breast cancer risk assessment and screening. Among those who subsequently underwent mobile screening, health insurance and time to additional diagnostic imaging and biopsy, when relevant, were retrospectively collected. RESULTS: 233 women completed surveys (mean age 54 ± 13 years). Ninety-three percent of respondents identified as Black. The most frequently cited barrier to screening mammography was cost and/or lack of insurance coverage (30%). Women under 50 reported more barriers to screening compared to older women. Among those recalled from screening and recommended to undergo biopsy, there was a trend toward longer delays between screening and biopsy among those without a PCP (median 45 days, IQR 25-53) compared to those with a PCP (median 24 days, IQR 16-29) (p = 0.072). CONCLUSION: In a study of a medically underserved community of primarily Black patients, barriers to breast cancer risk assessment, screening, and diagnosis were identified by self-report and by documented care delays. While free mobile mammography initiatives that bring medical professionals into communities can help mitigate barriers to screening, strategies for navigation and coordination of follow-up are critical to promote timely diagnostic resolution for all patients.

Protocol for a pragmatic stepped wedge cluster randomized clinical trial testing behavioral economic implementation strategies to increase supplemental breast MRI screening among patients with extremely dense breasts.

BACKGROUND: Increased breast density augments breast cancer risk and reduces mammography sensitivity. Supplemental breast MRI screening can significantly increase cancer detection among women with dense breasts. However, few women undergo this exam, and screening is consistently lower among racially minoritized populations. Implementation strategies informed by behavioral economics ("nudges") can promote evidence-based practices by improving clinician decision-making under conditions of uncertainty. Nudges directed toward clinicians and patients may facilitate the implementation of supplemental breast MRI. METHODS: Approximately 1600 patients identified as having extremely dense breasts after non-actionable mammograms, along with about 1100 clinicians involved with their care at 32 primary care or OB/GYN clinics across a racially diverse academically based health system, will be enrolled. A 2 × 2 randomized pragmatic trial will test nudges to patients, clinicians, both, or neither to promote supplemental breast MRI screening. Before implementation, rapid cycle approaches informed by clinician and patient experiences and behavioral economics and health equity frameworks guided nudge design. Clinicians will be clustered into clinic groups based on existing administrative departments and care patterns, and these clinic groups will be randomized to have the nudge activated at different times per a stepped wedge design. Clinicians will receive nudges integrated into the routine mammographic report or sent through electronic health record (EHR) in-basket messaging once their clinic group (i.e., wedge) is randomized to receive the intervention. Independently, patients will be randomized to receive text message nudges or not. The primary outcome will be defined as ordering or scheduling supplemental breast MRI. Secondary outcomes include MRI completion, cancer detection rates, and false-positive rates. Patient sociodemographic information and clinic-level variables will be examined as moderators of nudge effectiveness. Qualitative interviews conducted at the trial's conclusion will examine barriers and facilitators to implementation. DISCUSSION: This study will add to the growing literature on the effectiveness of behavioral economics-informed implementation strategies to promote evidence-based interventions. The design will facilitate testing the relative effects of nudges to patients and clinicians and the effects of moderators of nudge effectiveness, including key indicators of health disparities. The results may inform the introduction of low-cost, scalable implementation strategies to promote early breast cancer detection. TRIAL REGISTRATION: ClinicalTrials.gov NCT05787249. Registered on March 28, 2023.

Cumulative environmental quality is associated with breast cancer incidence differentially by summary stage and urbanicity.

Individual environmental contaminants have been associated with breast cancer; however, evaluations of multiple exposures simultaneously are limited. Herein, we evaluated associations between breast cancer summary stages and the Environmental Quality Index (EQI), which includes a range of environmental factors across five domains. The EQI (2000-2005) was linked to county-level age-standardized incidence rates (SIRs) obtained from the North Carolina Central Cancer Registry (2010-2014). Incidence rates and SIRs of total, in situ, localized, regional, and distant breast cancers were evaluated stratified by rural-urban status. In counties with poor environmental quality compared to those with good environmental quality, total breast cancer incidence was higher by 10.82 cases per 100,000 persons (95% CI 2.04, 19.60, p = 0.02). This association was most pronounced for localized breast cancer (ß = 5.59, 95% CI 0.59, 10.58, p = 0.03). Higher incidence of early-stage disease (carcinoma in situ ß = 5.25, 95% CI 2.34, 8.16, p = 0.00 and localized breast cancer ß = 6.98, 95% CI 2.24, 11.73, p = 0.00) and total breast cancer (ß = 11.44, 95% CI 3.01, 19.87, p = 0.01) occurred in counties with poor land quality, especially urban counties. Our analyses indicate significant associations between environmental quality and breast cancer incidence, which differ by breast cancer stage and urbanicity, identifying a critical need to assess cumulative environmental exposures in the context of cancer stage.

Protocol to evaluate sequential electronic health record-based strategies to increase genetic testing for breast and ovarian cancer risk across diverse patient populations in gynecology practices.

BACKGROUND: Germline genetic testing is recommended by the National Comprehensive Cancer Network (NCCN) for individuals including, but not limited to, those with a personal history of ovarian cancer, young-onset (< 50 years) breast cancer, and a family history of ovarian cancer or male breast cancer. Genetic testing is underused overall, and rates are consistently lower among Black and Hispanic populations. Behavioral economics-informed implementation strategies, or nudges, directed towards patients and clinicians may increase the use of this evidence-based clinical practice. METHODS: Patients meeting eligibility for germline genetic testing for breast and ovarian cancer will be identified using electronic phenotyping algorithms. A pragmatic cohort study will test three sequential strategies to promote genetic testing, two directed at patients and one directed at clinicians, deployed in the electronic health record (EHR) for patients in OB-GYN clinics across a diverse academic medical center. We will use rapid cycle approaches informed by relevant clinician and patient experiences, health equity, and behavioral economics to optimize and de-risk our strategies and methods before trial initiation. Step 1 will send patients messages through the health system patient portal. For non-responders, step 2 will reach out to patients via text message. For non-responders, Step 3 will contact patients' clinicians using a novel "pend and send" tool in the EHR. The primary implementation outcome is engagement with germline genetic testing for breast and ovarian cancer predisposition, defined as a scheduled genetic counseling appointment. Patient data collected through the EHR (e.g., race/ethnicity, geocoded address) will be examined as moderators of the impact of the strategies. DISCUSSION: This study will be one of the first to sequentially examine the effects of patient- and clinician-directed strategies informed by behavioral economics on engagement with breast and ovarian cancer genetic testing. The pragmatic and sequential design will facilitate a large and diverse patient sample, allow for the assessment of incremental gains from different implementation strategies, and permit the assessment of moderators of strategy effectiveness. The findings may help determine the impact of low-cost, highly transportable implementation strategies that can be integrated into healthcare systems to improve the use of genomic medicine. TRIAL REGISTRATION: ClinicalTrials.gov. NCT05721326. Registered February 10, 2023. https://www. CLINICALTRIALS: gov/study/NCT05721326.

Racial, Ethnic, and Gender Diversity Among Academic Surgical Leaders in the US.

Importance: Surgical department chairs remain conspicuously nondiverse despite the recognized importance of diverse physician workforces. However, the extent of diversity among non-chair leadership remains underexplored. Objective: To evaluate racial, ethnic, and gender diversity of surgical department chairs, vice chairs (VCs), and division chiefs (DCs) in the US. Design, Setting, and Participants: For this cross-sectional study, publicly accessible medical school and affiliated hospital websites in the US and Puerto Rico were searched from January 15 to July 15, 2022, to collect demographic and leadership data about surgical faculty. Two independent reviewers abstracted demographic data, with up to 2 additional reviewers assisting with coding resolution as necessary. In all, 2165 faculty were included in the analyses. Main Outcomes and Measures: Proportions of racial, ethnic, and gender diversity among chairs, VCs, and DCs in general surgery and 5 surgical specialties (neurosurgery, obstetrics and gynecology, ophthalmology, orthopedics, and otolaryngology). Results: A total of 2165 faculty (1815 males [83.8%] and 350 females [16.2%]; 109 [5.0%] African American or Black individuals; 347 [16.0%] Asian individuals; 83 [3.8%] Hispanic, Latino, or individuals of Spanish origin; and 1624 [75.0%] White individuals as well as 2 individuals [0.1%] of other race or ethnicity) at 154 surgical departments affiliated with 146 medical schools in the US and Puerto Rico were included in the analysis. There were more males than females in leadership positions at all levels-chairs (85.9% vs 14.1%), VCs (68.4% vs 31.6%), and DCs (87.1% vs 12.9%)-and only 192 leaders (8.9%) were from racial or ethnic groups that are underrepresented in medicine (URiM). Females occupied more VC than chair or DC positions both overall (31.6% vs 14.1% and 12.9%, respectively) and within racial and ethnic groups (African American or Black females, 4.0% VC vs 1.5% chair and 0.6% DC positions; P < .001). URiM individuals were most commonly VCs of diversity, equity, and inclusion (DEI, 51.6%) or faculty development (17.9%). Vice chairs of faculty development were split equally between males and females, while 64.5% of VCs for DEI were female. All other VCs were predominantly male. Among DC roles, URiM representation was greatest in transplant surgery (13.8%) and lowest in oral and maxillofacial surgery (5.0%). Except for breast and endocrine surgery (63.6% female), females comprised less than 20% of DC roles. Nearly half of DCs (6 of 13 [46.2%]) and VCs (4 of 9 [44.4%]) had no female URiM leaders, and notably, no American Indian, Alaska Native, or Native Hawaiian or Other Pacific Islander individuals were identified in any surgical leadership positions. Conclusions and Relevance: While it is unclear whether promotion from VC to chair or from DC to chair is more likely, these findings of similar gender distribution between chairs and DCs suggest the latter and may partially explain persistent nondiversity among surgical chairs. Female and URiM surgical leaders are disproportionately clustered in roles (eg, VCs of DEI or faculty development) that may not translate into future promotion to department chairs.

Addressing Inequalities in Breast Cancer Care Delivery.

Breast cancer treatment, timeliness of care, and clinical outcomes are inferior for patients of Black race and Hispanic ethnicity, and the origin of these inequities is multifactorial. Owing to aggregate reporting of data in the United States for patients of Asian, Native Hawaiian, and Pacific Islander ancestry, disparities within and across these groups are difficult to appreciate. In large part due to low prevalence, male breast cancer remains understudied, and treatment algorithms are primarily extrapolated from research conducted in female patients.

Impact of travel burden on the treatment of stage I and II breast cancer: A National Cancer Database analysis.

BACKGROUND: Although historic studies of state registries have demonstrated decreased radiation therapy use for patients with breast cancer living further away from radiation facilities, the association between travel distance and breast cancer treatment in a modern national cohort remains unknown. METHODS: Female patients with estrogen receptor/progesterone receptor positive and human epidermal growth factor receptor 2 negative pathologic stages I to II breast cancer were identified from the National Cancer Database (2018-2020) and dichotomized by distance ≤20 miles or >20 miles (75th percentile) from the treatment facility. The association between travel distance and type of surgery and treatment administered was analyzed by univariate and multivariate logistic regression and after 1:1 propensity matching. RESULTS: Of the 293,318 patients identified for inclusion, the median age was 63 years, and most patients (n = 190,567, 65%) lived ≤20 miles of the treatment facility. Patients with a travel burden >20 miles were more likely to receive a mastectomy (≤20 miles 30.4% vs >20 miles 34.0%, P < .001; odds ratio 1.14, P = .016), and less likely to receive radiation (≤20 miles 63.3% vs >20% miles 60.1%, P < .001; odds ratio 0.81, P < .001). These findings persisted after propensity score matching (n = 33,544 per cohort), with patients living further being more likely to undergo a mastectomy (≤20 miles 30.3% vs >20 miles 35.3%, P < .001) and less likely to receive radiation (≤ 20 miles 65.4% vs. >20 miles 58.5%, P < .001). CONCLUSION: Patients with hormone receptor-positive stage I to II breast cancer with a larger travel burden are more likely to receive a mastectomy and less likely to undergo radiation therapy to treat their disease.

Survey Study of Clerkship Curriculum on Learner's Choice to Pursue Surgery: Positive Impact of Extracurricular Opportunities.

OBJECTIVE: Prior studies have focused on the role of the learning environment on students' decisions to pursue surgery, but few have analyzed the impact of the clerkship curriculum. This study assessed surgical clerkship curricula across United States (US) medical schools and their impact on students' likelihood of pursuing a surgical residency. DESIGN: A cross-sectional survey was developed to assess surgery clerkship characteristics. Questions included clerkship duration, number of offered and required surgical services, method of service assignment, and number of advanced clinical electives (e.g., fourth-year sub-internships) and additional surgical clinical opportunities (e.g., surgical elective rotations). Survey results were merged by the Association of American Medical Colleges with the percentages of students who matched into a surgical specialty. Linear regression models estimated the association of covariates with the percentage of students who (1) matched in surgical specialties, (2) were interested in surgery at medical school matriculation and ultimately matched into surgical residency (retention rate), and (3) were not interested in surgery at medical school matriculation but ultimately matched into surgical residency (recruitment rate). SETTING: The survey was distributed to clerkship directors and coordinators at 66 medical schools through the Association for Surgical Education (ASE) from 5/1/2021 to 8/1/2021. PARTICIPANTS: All US medical schools in the ASE. RESULTS: A total of 21 medical schools responded (34.8% response rate). The overall retention rate was 36.4%, and the overall recruitment rate was 25.0%. Clerkships were 4 to 12 weeks. In 81% of programs, students submitted preferences and were assigned services. The percentage of students applying to surgical specialties was not associated with clerkship duration (p=0.79) or the number of required services (p=0.15), subspecialty services offered (p=0.33), or advanced clinical electives (p=0.24) but was associated with a program's having additional surgical clinical opportunities (p=0.02). Most of these factors were not associated with retention or recruitment rates. CONCLUSIONS: Offering more extracurricular surgical clinical opportunities was associated with having more students pursue surgical careers. Though limited by a relatively small sample size, our findings suggest that having shorter clerkships or limited subspecialty offerings may not have a significant influence on students' career choices.

Temporal Trends and Factors Associated with Receipt of Post-mastectomy Radiation After Neoadjuvant Chemotherapy in Women with cT3 Breast Cancer.

INTRODUCTION: Given the potential impact of increasingly effective neoadjuvant chemotherapy (NACT) on post-mastectomy radiotherapy (PMRT) recommendations, we examined temporal trends in post-NACT PMRT for cT3 breast cancer. METHODS: We identified women ≥ 18 years in the National Cancer Database (NCDB) diagnosed 2004-2019 with cT3N0-1M0 breast cancer treated with chemotherapy and mastectomy. Multivariable logistic regression and Cox proportional hazards models were used to estimate associations between pathologic NACT response [complete response (CR), partial response (PR), or no response (NR); or disease progression (DP)] and PMRT and between PMRT and overall survival (OS), respectively. RESULTS: We identified 39,901 women (Asian/Pacific Islander 1731, Black 5875, Hispanic 3265, White 27,303). Among cN0 patients with CR, PMRT rates declined from 67% in 2004 to 35% in 2019 but remained unchanged for patients with DP. Relative to NR, CR [odds ratio (OR) 0.36, 95% confidence interval (CI) 0.29-0.46] and PR (OR 0.44, 95% CI 0.36-0.55) in cN0 patients were associated with lower odds of PMRT while DP (OR 1.33, 95% CI 1.05-1.69) was associated with higher odds. Among cN1 patients, PMRT rates decreased from 90% to 73% for CR between 2005 and 2019 and increased from 76% to 82% for DP between 2004 and 2019. Relative to NR, CR (OR 0.78, 95% CI 0.63-0.95) was associated with lower odds of PMRT while DP (OR 1.93, 95% CI 1.58-2.37) was associated with higher odds. PMRT was associated with improved OS among cN1 patients (hazard ratio (HR) 0.77, 95% CI 0.67-0.88). CONCLUSION: CR was associated with decreased PMRT receipt over time, while temporal trends following PR and DP differed by cN status, suggesting that nodal involvement guided PMRT receipt more than in-breast disease.