Rapid Fire 1

H. Park¹, J. Ryu², J. Lee³, H. Kim⁴, S. Lee⁵, H. Lee⁶, Y. Kang⁷, J. Kim⁸, H. Choi⁹, K. Kim¹⁰, H. Shin¹¹, A. Han¹², Y. Lee¹³, J. Cheun¹⁴, M. Lee¹⁵, J. You¹⁶, S. Bae¹⁷, Y. Kim¹⁸, N. Kim¹⁹; ¹Department of Surgery, Yonsei University College of Medicine, Seoul, KOREA, REPUBLIC OF, ²Department of Surgery, Sungkyunkwan University School of Medicine, Gangnam-gu, Seoul, KOREA, REPUBLIC OF, ³Department of Surgery, Kyungpook National University School of Medicine, Buk-gu, Daegu, KOREA, REPUBLIC OF, ⁴Department of Surgery, Seoul National University College of Medicine, Jongno-gu, Seoul, KOREA, REPUBLIC OF, ⁵Department of Surgery, University of Ulsan College of Medicine, Songpa-gu, Seoul, KOREA, REPUBLIC OF, ⁶Department of Surgery, Korea University Ansan Hospital, Danwon-gu, Ansan-si, KOREA, REPUBLIC OF, ⁷Department of Surgery, Incheon St. Mary’s Hospital, Bupyeong-gu, Incheon, KOREA, REPUBLIC OF, ⁸Department of Surgery, Yonsei University College of Medicine, Giheung-gu, Yongin-si, KOREA, REPUBLIC OF, ⁹Department of Surgery, Sungkyunkwan University School of Medicine, Masanhoewon-gu, Changwon-si, KOREA, REPUBLIC OF, ¹⁰Department of Surgery, Kosin University College of Medicine, Seo-gu, Busan, KOREA, REPUBLIC OF, ¹¹Department of Surgery, Myongji Hospital, Deogyang-gu, Goyang-si, KOREA, REPUBLIC OF, ¹²Department of Surgery, Wonju College of Medicine, Wonju-si, Gangwon, KOREA, REPUBLIC OF, ¹³Department of Surgery, Chungnam National University Sejong Hospital, Sejong-si, KOREA, REPUBLIC OF, ¹⁴Department of Surgery, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Dongjak-gu, Seoul, KOREA, REPUBLIC OF, ¹⁵Department of Surgery, Soonchunhyang University Hospital, Yongsan-gu, KOREA, REPUBLIC OF, ¹⁶Department of Surgery, Korea University Anam hospital Korea University College of Medicine, Seongbuk-gu, Seoul, KOREA, REPUBLIC OF, ¹⁷Department of Surgery, Yonsei University College of Medicine, Gangnam-gu, Seoul, KOREA, REPUBLIC OF, ¹⁸Department of Surgery, Korea University Guro Hospital Korea University College of Medicine, Guro-gu, Seoul, KOREA, REPUBLIC OF, ¹⁹Department of Biostatistics and Computing, Yonsei University Graduate School, Seodaemun-gu, KOREA, REPUBLIC OF.

Background: Minimally invasive breast surgery (MIS), including robotic and endoscopic mastectomy, has emerged as an alternative to conventional mastectomy (CM). However, robust prospective multicenter data comparing postoperative complications between MIS and CM have been lacking. Methods: The MARRES study (NCT004585074) is a multicenter, prospective cohort was conducted at 18 institutions in South Korea. Women with breast cancer or BRCA1/2 mutation carriers who underwent total, skin-sparing, or nipple-sparing mastectomy followed by immediate breast reconstruction were enrolled. The primary endpoint is the rate of postoperative complications of Clavien-Dindo grade ≥3 between the MIS and CM groups. A prespecified non-inferiority analysis with 1:1 matching was conducted according to the protocol. Results: A total of 1,914 women (2,140 cases) were enrolled. After applying eligibility criteria, 1,875 women were included in the analysis: 584 underwent MIS and 1,291 underwent CM. A total of 2,095 cases were analyzed, including 678 MIS cases (52 endoscopic and 626 robotic) and 1,417 CM cases. Among them, 615 cases (90.7%) in the MIS group and 1,358 cases (95.8%) in the CM group were performed for breast cancer, while the remaining cases involved benign disease or risk-reducing mastectomy in BRCA1/2 mutation carriers. Meanwhile, out of 1,875 women analyzed, 253 women (13.5%) underwent bilateral mastectomy, of which 116 women (45.8%) were diagnosed with bilateral breast cancer. Among women with unilateral breast cancer (N=1,616), those undergoing MIS were younger (median age, 46.0 vs. 47.0 years; p=0.0003) and more frequently aged <50 years (69.9% vs. 61.4%; p=0.0012). The MIS group had a higher prevalence of normal to mild breast ptosis (74.7% vs. 52.1%; p<0.0001) and more frequently presented with early-stage disease, including preoperative diagnoses of DCIS (37.8% vs. 28.9%; p=0.001). In terms of tumor biology, the MIS group had higher rates of progesterone receptor positivity (72.8% vs. 66.6%; p=0.033), HER2 negativity (71.1% vs. 68.6%; p=0.002), and low Ki-67 expression (41.0% vs. 30.0%; p<0.0001). Postoperative complications of Clavien-Dindo grade ≥3 were significantly lower in the MIS group than in the CM group (11.2% vs. 19.3%; p<0.0001). Overall complication rates were also lower in the MIS group, with a higher proportion of patients experiencing no complications (Grade 0: 71.2% vs. 61.7%; p<0.0001). Early postoperative complications (within 30 days) occurred less frequently in the MIS group than in the CM group (25.7% vs. 33.5%; p=0.0003). No significant difference was observed in late complications (beyond 30 days) between the two groups (10.8% vs. 13.5%; p=0.073). In the prespecified 1:1 matched analysis, Clavien-Dindo grade ≥3 complications were reported in 9.5% of MIS cases and 18.0% of CM cases, with an absolute difference of -8.5%, satisfying the predefined non-inferiority margin of 5%. Conclusion: This study indicates that MIS is not inferior to CM followed by reconstruction regarding severe complication rates; furthermore, MIS shows better outcomes of postoperative complication rates in the early postoperative period. MIS is safely administered in breast surgery in terms of surgical outcomes.

A. M. Leitch¹, T. Dockter², V. suman³, A. Weiss⁴, G. W. Unzeitig⁵, J. Guenther⁶, S. Sanati⁷, K. Vij⁸, J. Hoog⁹, A. Caudle¹⁰, A. Tiersten¹¹, M. Mita¹², W. Razaq¹³, T. J. Hieken¹⁴, Y. Wang¹⁵, M. Rimawi¹⁶, M. J. Ellis¹⁷, E. Winer¹⁸, K. K. Hunt¹⁹, A. H. Partridge²⁰, L. A. Carey²¹; ¹Surgery, UT Southwestern Medical Center, Dallas, TX, ²Alliance Statistics and Data Management Center,, Mayo CLinic, Rochester, MN, ³Alliance Statistics and Data Management Center, Mayo Clinic, Rochester, MN, ⁴Surgery, University of Rochester, Rochester, NY, ⁵Surgery, Doctor’s Hospital of Laredo, Laredo, TX, ⁶Surgery, Saint Elizabeth Medical Center South, Edgewood, KY, ⁷Pathology, Cedars-Sinai Medical Center, Los Angeles, CA, ⁸Medical Oncology, Washington University School of Medicine, St. Louis, MO, ⁹Division of Oncology, Washington University School of Medicine, St. Louis, MO, ¹⁰Department of Breast Surgical Oncology, MD Anderson Cancer Center,, Houston, TX, ¹¹Internal Medicine, Mount Sinai Hospital, New York, NY, ¹²Medical Oncology, Cedars-Sinai Medical Center, Los Angeles, CA, ¹³Medical Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, ¹⁴Surgical Oncology, Mayo Clinic, Rochester, MN, ¹⁵Medical Oncology, Presbyterian Kaseman Hospital, NM, Albuquerque, NM, ¹⁶Medical Oncology, Baylor College of Medicine, Houston, TX, ¹⁷Medical Oncology, Guardant Health, Palo Alto, CA, ¹⁸Medical Oncology, Yale School of Medicine,, New Haven, CT, ¹⁹Department of Breast Surgical Oncology, MD Anderson Cancer Center TX, Houston, TX, ²⁰Medical Oncology, Dana-Farber/Partners CancerCare, Boston, MA, ²¹Medical Oncology, University of North Carolina Medical Center, Chapel Hill, NC.

Background: While there are abundant data on the surgical management of BC after neoadjuvant chemotherapy (NAC), there is less guidance regarding surgical management of BC after NET, particularly with respect to lymph node (LN) surgery. While pathologic complete response (pCR) is common with NAC, it is a rare event with NET. In this analysis we assess the surgeons’ approach in the context of NET.Methods: The ALTERNATE trial is a phase III study that randomized postmenopausal patients (pts) with clinical stage II/III ER+ HER2- BC to receive neoadjuvant anastrozole (A), fulvestrant (F), or both for 6 mos. before surgery. The primary objective was to determine if neoadjuvant F or A+F increases the rate of pCR or ypT1-2N0/N1mic/Ki67 <2.7% residual disease over A alone. Breast surgery was per standard of care. Sentinel lymph node biopsy (SLNB) with or without axillary lymph node dissection (ALND) was required to determine preoperative endocrine prognostic index PEPI score and residual cancer burden (RCB). Surgeons were required to indicate if the patient would be eligible for breast- conserving surgery (BCS) prior to NET. Patient accrual occurred from 2014-2018. The surgical outcomes are reported for the entire group. Results: Among the 3 treatment arms, 933 patients completed 6 cycles of NET. The clinical T stage at diagnosis was 73.6% T2, 22.6% T3and 3.8% T4. Initial tumor size was assessed by mammogram and ultrasound. Primary tumor histology was ductal in 64.8% and lobular in 25.4%.568 pts (60.9%) were clinically node negative (cN0), 36.2% cN1, 2.6% cN2 with 0.3% cN3. LNs were palpable in 25.2%. 383 had LN needle biopsy pre NET, of which 80.9% were positive. The surgeons’ initial impression of the patient’s eligibility for BCS was 74% while 0.6% were considered inoperable.75.5% of pts had post-NET imaging performed. Of those with tumor size recorded , 52.9% were T1 or not visible. Overall, 69.9% of the 933 patients had BCS. Of those 330 pts without post-NET imaging or who had post-NET imaging without a size noted, 64.8% underwent BCS. For pts undergoing BCS, 80.2% required only one surgery for margin clearance. Of the 690 pts deemed eligible for BCS pre NET, 79% had BCS. Of the 240 pts deemed ineligible for BCS pre-NET, 43.8% had BCS. Of the pre-NET cT2 tumors, 79% had BCS while only 45.5% of T3 tumors and 37.1% of T4 tumors had BCS .On surgical pathology, 474 (50.8%) pts were LN+ compared to pre-NET cN+ 39.1% and needle biopsy-proven 33.2%. For pts with pN0, 93.3% had SLNB alone. 6.7 % of pN0 had ALND alone or SLNB+ALND. For those with pN1-3 , 36.3% had SLN only; 37.3% SLN+ ALND; 26.4% ALND alone. Only 0.8% of the patients had no ALND or SLNB performed. Pts undergoing BCS were more likely to have SLNB alone for a +SLN compared to mastectomy pts (62.9% vs. 37.6%; chi-square p<0.0001). For pts with pre-NET +LN on needle biopsy, only 26.8% underwent SLNB alone, while 37.4% underwent ALND alone.Of the 204 LN-positive pts having SLNB alone, 55.9% had only 1 + LN and 27% had only 2+ LNs. For pN+ pts who underwent SLNB +ALND, 42.1% had 1-2 + LNs. Conclusion:With NET, 69.9% of pts achieved BCS, including 43.8% deemed ineligible pre-NET. Given the low rate of pCR to NET, there should not be the expectation of pCR in +LNs. Based on the procedures performed in pts with +SLNs, it appears that surgeons were applying ACOSOG Z0011 criteria for pts having BCS, but were less likely to omit ALND for +LN in pts having mastectomy. The finding of only 1-2 +LNs in many of the LN+ pts suggests that omission of ALND may be a reasonable approach post-NET. Longer follow-up is required to assess local-regional recurrence.Support: U10CA180821, U10CA180882; https://acknowledgments.alliancefound.org. Clinical Trials.gov Identifier: NCT01953588

Y. Peng, Y. Xiang, J. Tie, S. Zhang, C. Shi, C. Guo, W. Wang; Department of Radiation Oncology, Peking University Cancer Hospital and Institute, Beijing, CHINA.

Background:Internal mammary node (IMN) metastasis is an adverse prognostic factor in breast cancer. While surgical dissection of IMNs is rarely performed due to its invasiveness and lack of proven survival benefit, internal mammary node irradiation (IMNI) remains the standard approach for managing clinically positive IMNs. With the increasing use of neoadjuvant therapy (NAT), a critical question emerges—whether a boost to the region of IMN metastasis is still necessary when an imaging based complete nodal response was observed. This study aims to evaluate whether omitting a postoperative IMN boost is oncologically safe in patients with baseline imaging-positive IMNs who achieve an IMN clinical complete response (icCR) following NAT.Methods:This retrospective cohort study included 1326 female breast cancer patients treated between 2018 and 2021 at our center. Inclusion criteria were: (1) histological confirmed invasive breast cancer with M0; (2) received standard NAT; (3) underwent breast-conserving or modified radical mastectomy; (4) received postoperative radiotherapy with IMNI; (5) underwent pre- and post-NAT breast magnetic resonance imaging (MRI). IMN metastasis was defined by MRI features including short-axis diameter ≥5 mm and suspicious morphological features, such as loss of hilum or high-signal in diffusion weighted imaging. IcCR was defined as complete disappearance of all previously positive IMNs on post-NAT MRI. All imaging was independently reviewed by two radiation oncologists, with discrepancies resolved by consensus. The postoperative IMNI regimen delivered 50 Gy in 25 fractions to IMN, with a subset of patients receiving a simultaneous integrated boost to 60 Gy to the pre-NAT involved internal mammary node site. Prognosis was evaluated by disease-free survival (DFS), local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and overall survival (OS). Multivariable analysis was performed using Firth-corrected Cox regression. Sensitivity analyses including standard Cox and Bayesian Cox models with informative priors were utilized to validate the robustness of findings. Interaction between icCR status and IMN boost was also evaluated. Results:Of 1326 patients, 208 (15.7%) presented with imaging-positive IMN at baseline. The median follow-up was 53 months. IMN-positive patients had significantly worse 3-year DFS than IMN-negative patients (85.3% vs. 94.9%, HR=3.48, P<0.001). Among IMN-positive patients, 132 (63.5%) achieved icCR. Neither icCR (HR=0.63, 95%CI: 0.30-1.33, P=0.226) nor IMN boost (HR=0.71, 95%CI: 0.35-1.46, P=0.350) were independent predictors of DFS. However, a significant interaction between icCR status and IMN boost was observed (HR for interaction=2.79, 95%CI: 1.02-7.61, P for interaction=0.045), confirmed by Bayesian analysis (posterior HR=1.85, 95%CrI: 1.15-3.80, posterior P= 0.978). Subgroup analysis showed that an IMN boost did not improve DFS in icCR patients (HR=1.06, 95%CI: 0.41-2.78, P=0.899), but significantly reduced risk by 70% in non-icCR patients (HR=0.30, 95%CI: 0.10-0.88, P=0.029). For other endpoints, no significant interactions between icCR and IMN boost were found, although a trend was noted for DMFS (P for interaction = 0.078), and the analyses may have been underpowered due to a limited number of events.Conclusion:Achieving icCR post-NAT is not an independent prognostic factor but serves as a predictive marker for IMN boost benefit. A postoperative IMN boost confers substantial DFS benefit in patients with residual disease but may be safely omitted in those achieving icCR. These findings support a risk-adapted radiation strategy and warrant validation in prospective and multi-institutional cohorts.

A. Basu¹, S. Umashankar¹, C. Yau¹, K. J. Ruddy², A. H. Blaes³, D. M. Wolf⁴, A. DeMichele⁵, J. Perlmutter⁶, D. Yee⁷, A. B. Olshen⁸, L. J. van’t Veer⁴, R. A. Shatsky⁹, C. Isaacs¹⁰, R. Nanda¹¹, H. S. Rugo¹², M. E. Melisko¹², N. Hylton¹³, L. J. Esserman¹, D. L. Hershman¹⁴, I-SPY Trial Investigators and Patient Advocates; ¹Department of Surgery, University of California San Francisco, San Francisco, CA, ²Department of Oncology, Mayo Clinic, Rochester, MN, ³Division of Hematology and Oncology, University of Minnesota, Minneapolis, MN, ⁴Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, ⁵Division of Hematology Oncology, University of Pennsylvania, Philadelphia, PA, ⁶Gemini Group, Gemini Group, Ann Arbor, MI, ⁷Department of Surgery, University of Minnesota, Minneapolis, MN, ⁸Dept. of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, ⁹Department of Medicine, University of California San Diego, La Jolla, CA, ¹⁰Department of Medicine, Georgetown University, Washington, DC, DC, ¹¹Department of Medicine, University of Chicago, Chicago, IL, ¹²Department of Medicine, University of California San Francisco, San Francisco, CA, ¹³Department of Radiology, University of California San Francisco, San Francisco, CA, ¹⁴Department of Medicine, Columbia University, New York, NY.

Background: Advances in oncology, particularly the adoption of immunotherapies and antibody-drug conjugates, are transforming the nature and frequency of adverse events (AEs). These AEs come with both short and long-term symptoms that significantly impact patient quality of life. Monitoring for early onset of symptoms could optimize personalized therapy, maximizing potential efficacy while mitigating toxicity. It is also possible that some toxicities are directly associated with drug sensitivity. We sought to identify symptoms associated with pathologic complete response (pCR) using patient-reported outcomes (PROs) in early-stage high-risk breast cancer patients. Methods: Our study population included 288 stage II/III high-risk breast cancer patients enrolled on the I-SPY2 trial from 2021-2024, who received IO and ADC neoadjuvant therapies ± standard paclitaxel. pCR was defined as tumor absent in breast and nodes at surgery following neoadjuvant treatment. Patients (n = 288) were sent electronic PROs. 33 patient-reported AEs were measured using NCI’s Patient Reported Outcomes – Common Terminology Criteria for Adverse Events (PRO-CTCAE). Each symptom was evaluated using severity, frequency, and interference on a Likert Scale. Presence of early PRO symptoms (cycles 1-3 of treatment) were categorized (at least one of moderate or greater), and odds ratios were computed with pCR as outcome. To assess whether higher grade AEs were enriched in patients that achieved a pCR, we also performed the Wilcoxan Rank Sum test using maximum (worst) symptom severity. Breast tumor volume was measured by MRI at baseline and again at cycle 3 (~day 21 from treatment start). Functional tumor volume (FTV) was computed from MR images by using enhancement thresholds. and percent change from baseline (ΔFTV) was calculated. Reduction in FTV was defined as a positive change. The Benjamini-Hochberg method was used to adjust for multiple hypothesis testing. Results: Of 288 patients included in our analysis (median age = 48 years, range = 20-78, pCR rate = 29%), 203 (70.5%) were White, 17 (5.9%) were Asian, 33 (11.5%) were Black or African American, and 35 (12.2%) were Hispanic and 89% were administered immunotherapy, 11% ADC. The pCR rate was 29%. PRO analysis revealed that patients that had moderate to severe muscle pain (27% vs 10% OR = 3.15, P < 0.05), joint pain (22% vs 8% OR = 3.23, P < 0.05), headache (27% vs 12.5% OR = 2.59, P < 0.05), or mouth/throat sores (16% vs 5% OR = 3.56, p < 0.05) within weeks 1-3 had higher odds of achieving a pCR. Maximum severity between weeks 1-3 was associated with pCR. Patients that achieved a PCR had higher grade muscle pain (P < 0.05), heart rates of palpitations (P < 0.05), and significantly lower grade numbness and tingling (p = 0.002). Additionally, of the symptoms assessed, frequency, interference, and severity of arm or leg swelling was significantly correlated with reduction in tumor volume (FTV) during weeks 1-3 treatment (Bonferroni corrected P<0.01). Beyond 6 weeks, associations were weak or insignificant. Conclusion: Our study utilizes a computational framework that defined sentinel symptoms such as muscle and joint pain, mouth/throat sores, headache, and swelling, as early as weeks 1-3 that were associated with a favorable tumor response. This may suggest an early immune reaction in patients that eventually respond favorably to treatment, and prioritization to continue these patients on treatment may be warranted. Our work can help provide earlier proactive monitoring to mitigate toxicities, to enhance treatment response, and a potential symptom-based early understanding to personalize treatment efficacy.

S. A. Manobianco¹, A. Lopez¹, D. P. Silver¹, A. P. Scarpaci², R. J. Jaslow¹, S. Bhattacharya¹, F. M. Fellin³, P. Suresh³, A. M. Zibelli¹, J. Rodriguez³, K. C. Degen⁴, S. A. Patel³, A. R. MacKenzie³, P. Anne⁵, S. B. Rudoler⁶, N. L. Simone⁵, I. Chervoneva⁷, M. Abu-Khalaf¹; ¹Department of Medical Oncology, Sidney Kimmel Comprehensive Cancer Center – Jefferson Health, Philadelphia, PA, ²Department of Medical Oncology, Sidney Kimmel Comprehensive Cancer Center – Cherry Hill, Cherry Hill, NJ, ³Department of Medical Oncology, Sidney Kimmel Comprehensive Cancer Center – Jefferson Health Asplundh Cancer Pavilion, Willow Grove, PA, ⁴Department of Medical Oncology, Sidney Kimmel Comprehensive Cancer Center – Torresdale, Philadelphia, PA, ⁵Department of Radiation Oncology, Sidney Kimmel Comprehensive Cancer Center – Jefferson Health, Philadelphia, PA, ⁶Department of Radiation Oncology, Sidney Kimmel Comprehensive Cancer Center – Torresdale, Philadelphia, PA, ⁷Department of Pharmacology, Physiology, and Cancer Biology, Thomas Jefferson University, Philadelphia, PA.

Background: Non-adherence to adjuvant endocrine therapy (ET) remains a significant clinical challenge. Technologies such as smart devices, electronic messaging, and telehealth offer new approaches to improving adherence. We hypothesized that more frequent monitoring with either electronic medical record (EMR) surveys to assess patient-reported outcomes (ePROs) or smart pill bottles would improve adjuvant ET adherence. Methods: In this phase II, multi-site within a single institution, randomized control investigator-initiated clinical trial, 285 patients receiving adjuvant ET within the first four years of an early stage breast cancer diagnosis were randomly assigned (1:1:1) to either A) standard of care monitoring (SOC) with visits every 3 months, B) SOC plus electronic surveys every 3 weeks, or C) SOC plus an interactive smart pill bottle to assess real-time adherence to ET for 12 months. Data indicating non-adherence, desire to stop ET, or severe toxicity triggered research staff follow-up and in-office or telehealth visits. The primary endpoint was ET adherence, defined as prescriptions filled to cover ≥80% of ET doses plus either self-reported ingesting ≥80% of doses (Arm A and B) or smart pill bottle dispense data (Arm C). 95 patients per arm provided 80% power to detect a difference between 65% adherence in the control arm and 85% adherence in each intervention arm with a significance level of 0.025. Secondary analyses included the effects of year of ET (year 1-4), age (≥50 vs <50 years old), baseline ET agent (aromatase inhibitors vs tamoxifen), and race (Black or African American vs White). Results: A total of 285 patients were randomized (96 to SOC, 94 to SOC + ePROs, and 95 to SOC + smart pill bottle). Features including age, ethnicity, stage, baseline ET agent, and year of ET were well-balanced between arms. 173 patients required additional follow-up beyond SOC monitoring, most commonly due to severe/very severe side effects (n=119). At 6 months, adherence on each arm was 70.8%, 61.7%, and 82.1% respectively; at 12 months, adherence was 53.1%, 45.7%, and 69.5%, statistically worse across all arms (OR 0.49; 95% CI 0.40-0.60, p<0.001). Compared to Arm A, the use of the smart pill bottle (Arm C) was associated with a significant improvement in adherence (OR 1.97; 95% CI 1.10-3.51, p=0.022), whereas the addition of ePRO monitoring (Arm B) resulted in a numerically worse but statistically insignificant decrease in adherence (OR 0.69; 95% CI 0.40-1.20, p=0.187). In secondary analysis, no difference in adherence was seen when stratified for year of ET (p=0.062), age (OR 1.29, CI 0.71-2.35, p=0.396), baseline ET agent (OR 1.39, CI 0.71-2.73, p=0.340), or race (OR 0.98, CI 0.57-1.71, p=0.952). Conclusion: The use of smart pill bottles nearly doubled the odds of adhering to adjuvant ET compared to standard of care monitoring, suggesting benefit from adoption of this novel technology.

A. Ozaki¹, K. Gonda¹, A. Hara², A. Ajitomi¹, M. Wada³, K. Tachibana⁴, M. Arai⁵, K. Konuma⁵, T. Sawano⁶, Y. Kanemoto⁶, H. Miyatake⁷, T. Kurokawa⁶, Y. Kouchi⁸, N. Kanzaki⁶, Y. Kotera⁹, Y. Takebayashi¹⁰, M. Murakami¹¹, T. Ohtake⁴, H. Shimmura⁸; ¹Breast and Thyroid Center, Jyoban Hospital of Tokiwa Foundation, Iwaki, JAPAN, ²Clinical Research Center, Jyoban Hospital of Tokiwa Foundation, Iwaki, JAPAN, ³Department of Breast Surgery, Utsunomiya Central Clinic, Utsunomiya, JAPAN, ⁴Department of Breast Surgery, Fukushima Medical University School of Medicine, Fukushima, JAPAN, ⁵Department of Nursing, Jyoban Hospital of Tokiwa Foundation, Iwaki, JAPAN, ⁶Department of Surgery, Jyoban Hospital of Tokiwa Foundation, Iwaki, JAPAN, ⁷Not applicable, Yushoukai Medical Corporation Nobishiroclinic Fujisawa, Iwaki, JAPAN, ⁸Department of Urology, Jyoban Hospital of Tokiwa Foundation, Iwaki, JAPAN, ⁹School of Health Sciences, Institute of Mental Health, University of Nottingham, Nottingham, UNITED KINGDOM, ¹⁰Department of Health Risk Communication, Fukushima Medical University School of Medicine, Fukushima, JAPAN, ¹¹Center for Infectious Disease Education and Research, The University of Osaka, Suita, JAPAN.

Background: While Advance Care Planning (ACP) is critical for respecting patient autonomy, a significant gap exists in the quantitative understanding of the specific discordance in values and preferences between Japanese cancer patients and their families. This study aimed to deconstruct these potential conflicts by moving beyond item-by-item comparisons to an analysis of their underlying conceptual structures. Methods: Self-administered questionnaires were distributed at Breast and Thyroid Center, Jyoban Hospital, from August 1, 2024, to May 31, 2025. A total of 470 outpatients with breast cancer and 324 family members responded to the survey. For the primary dyadic analysis, a final matched sample of 218 patients and their 324 family members was used. Descriptive statistics were first calculated for all variables. Generalized Linear Mixed-Effects Models (GLMM) were employed to examine differences in preferences while accounting for the one-to-many dyadic structure, with intraclass correlation coefficients confirming model appropriateness. Chi-squared tests with Bonferroni correction were used to analyze the association between preferences and the patient’s choice of surrogate. Multiple Correspondence Analysis (MCA) was then performed to identify the latent structures of “Life Priorities and Values” and “End-of-Life Care Preferences. Results: The initial descriptive analysis of the full 470-patient cohort revealed that “Independence in Activities of Daily Living (ADL)” (85.7%) and “Not being a burden to family” (76.4%) were the most frequently endorsed priorities. Within the dyadic sample, the most prevalent preference among family members was “Engagement in enjoyable and meaningful activities” (78.4%). Subsequent GLMM analysis confirmed significant discordance. Patients systematically prioritized autonomy and avoiding burden, with the odds of family members endorsing these values being substantially lower (e.g., for Independence in ADL, OR = 0.20, 95% CI [0.12, 0.34]; for Not being a burden to family, OR = 0.31, 95% CI [0.20, 0.48]; both p < .001). Conversely, families prioritized life prolongation and intervention, with the odds of endorsing “Longevity” being more than double those of patients (OR = 2.15, 95% CI [1.42, 3.24], p < .001) and the odds for “Receiving treatment until personal satisfaction is met” being 4.5 times higher (OR = 4.50, 95% CI [2.75, 7.37], p < .001). Subsequent GLMM analysis confirmed significant discordance. Patients systematically prioritized autonomy and avoiding burden (e.g., for Independence in ADL, OR for family vs. patient = 0.20), while families prioritized life prolongation and intervention (e.g., for Longevity, OR = 2.15; both p < .001). Furthermore, Chi-squared tests revealed that the designation of a spouse—but not a child—as a surrogate was significantly linked to distinct preference patterns. For instance, the choice of a spouse was significantly associated with the preference for “Prognostic awareness” within both the patient cohort (Cramér’s V = 0.25, p < .001) and the family cohort (Cramér’s V = 0.15, 95% CI [0.04, 0.26], p = .009). Crucially, MCA visualized this fundamental structural divergence: on a map of values, patients were oriented towards “self-reliance and not being a burden,” while families were oriented towards “survival, even with dependency.” Conclusion: This study is one of the first in Japan to quantitatively reveal, through dyadic modeling and conceptual mapping, that patients prioritize social independence and dignity, while families emphasize life preservation—a structural gap likely contributing to clinical conflict. Effective ACP should move beyond treatment choices and promote deeper dialogue to bridge these underlying worldviews and truly honor patient values.

A. Romanos-Nanclares¹, W. C. Willett², M. D. Holmes¹, W. Y. Chen³, B. A. Rosner¹, H. Eliassen¹; ¹Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, ²Harvard T. H. School of Public Health, Boston, MA, ³Dana Farber Cancer Institute, Boston, MA.

Objective: Cruciferous vegetables provide glucosinolate-derived compounds (e.g., isothiocyanates) that have inhibited breast cancer growth in experimental models, but epidemiologic evidence for a protective role remains limited and inconsistent. Therefore, we examined associations of cruciferous vegetable intake and total and subgroup-specific glucosinolates with breast cancer risk in the Nurses’ Health Study (NHS) and NHSII.Methods: We followed 76,713 women from the NHS [1984-2019] and 92,810 from the NHSII [1991-2019]. Diet was assessed by using validated semiquantitative food-frequency questionnaires at baseline and updated every 4 years during follow-up. We used Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for cumulative average cruciferous vegetable intake—including broccoli, cauliflower, cabbage/coleslaw, Brussels sprouts, and kale, mustard greens, or chard—and for energy-adjusted dietary glucosinolate intake in relation to the risk of invasive breast cancer and its subtypes, using the lowest intake category or quintile as the reference.Results: During 4,500,352 person-years of follow-up, 11,181 incident invasive breast cancer cases were identified across the two cohorts. Higher intake of cruciferous vegetables was associated with a statistically significantly lower breast cancer risk (>1 serving/day vs. <1 serving/week; HR=0.91, 95% CI: 0.84-0.98; P-trend1 serving/day vs. <1 serving/week; HR=0.83, 95% CI: 0.67-1.02; P-trend=0.01). Stratified analyses indicated a suggestive interaction by BMI (P-interaction=0.06), with stronger associations for ER-negative tumors among women with BMI<25 (HR=0.77, 95% CI: 0.55-1.07; P-trend=0.03) compared to those with BMI≥25 (HR=1.12, 95% CI: 0.83-1.51; P-trend=0.73). Furthermore, participants in the highest quintile of total glucosinolate intake had a lower breast cancer risk, including ER-negative, compared to the lowest quintile (overall HR=0.92, 95% CI: 0.87-0.98; P-trend<0.01 and ER-negative HR=0.87, 95% CI; 0.74-1.02; P-trend=0.03).Conclusions: Our findings support that higher intake of cruciferous vegetables may reduce the risk of breast cancer, especially those that are more likely to be aggressive tumors. Dietary glucosinolate intake was associated with a moderately lower risk of breast cancer. These findings contribute to the growing literature suggesting a protective effect of a potentially modifiable factor, cruciferous vegetable intake, on breast cancer risk. Mechanistic research is also needed to understand the relationship of exposures to glucosinolate metabolites with breast cancer risk.