Survival outcomes after omission of surgery for ductal carcinoma in situ.

Clinical trials of active surveillance (AS) for Ductal Carcinoma in Situ (DCIS) are underway. We sought to understand the historical management of biologically favorable DCIS and to determine the outcomes of patients who did not have immediate surgery. Using data from the NCDB from 2004 to 2017, the selected cohort included women >40 years of age, with low or intermediate grade and hormone receptor (HR) positive DCIS. AS was defined as either no surgery or surgery >12 months from diagnosis. Women in the AS group were compared to women who had immediate surgery. A Cochran-Armitage test was used to assess the trend of AS over year of diagnosis. Kaplan-Meier curves were estimated to compare overall survival (OS), stratified by age (<50, 50-64, ≥65), and Cox proportional hazard models were used to determine the effects of prognostic factors on survival distributions. 74,367 women met study inclusion criteria; 2384 (3.2%) were treated with AS. The proportion of patients in the AS cohort increased yearly, peaking in 2017 at 4.2% (p < 0.01). On multivariable analysis, increasing age (OR 1.02, p < 0.01), black race (OR 1.7, p < 0.001), and being uninsured (OR 2.2, p < 0.001) were associated with increased likelihood of AS. In women <50 years of age, OS outcomes were similar, with 10-year OS of 97.4% in the immediate surgery cohort versus 99.1% in AS cohort (p = 0.43). The proportion of patients with DCIS treated with AS has remained small but is increasing over time. AS of biologically favorable DCIS in younger, healthier women is not associated with adverse survival.

ATR inhibition radiosensitizes cells through augmented DNA Damage and G2 cell cycle arrest abrogation.

Ataxia telangiectasia and Rad3-related protein (ATR) is a key DNA damage response protein that facilitates DNA damage repair and regulates cell cycle progression. As such, ATR is an important component of the cellular response to radiation, particularly in cancer cells which show altered DNA damage response and aberrant cell cycle checkpoints. Therefore, ATR's pharmacological inhibition could be an effective radiosensitization strategy to improve radiotherapy. We assessed the ability of an ATR inhibitor, AZD6738, to sensitize cancer cell lines of various histologic types to photon and proton radiotherapy. We found that radiosensitization took place through persistent DNA damage and abrogated G2 cell cycle arrest. We also found that AZD6738 increased the number of micronuclei after exposure to radiotherapy. We found that combining radiation with AZD6738 led to tumor growth delay and prolonged survival relative to radiation alone in a breast cancer model. Combining AZD6738 with photons or protons also led to increased macrophage infiltration at the tumor microenvironment. These results provide a rationale for further investigation of ATR inhibition in combination with radiotherapy and with other agents such as immune checkpoint blockade.

Feasibility of breast conserving surgery alone in HER2-positive exceptional responders to neoadjuvant systemic therapy.

It is unknown if radiation therapy provides additional benefit among patients who achieve pathologic complete response (pCR) following neoadjuvant systemic therapy (NST). We sought to assess feasibility of radiation omission after breast conserving surgery in early-stage, node-negative, HER2+ breast cancer patients with pCR after NST. This was a single-arm study of women 30 years and older with cT2N0 disease based on imaging. Six patients were followed with mammography or MRI every 6 months following surgery. The median age of patients was 58 years (IQR: 46-66). At a median follow-up of 31.6 months (range: 21-40 months), no Ipsilateral Breast Tumor Recurrences (IBTR) were identified. This approach was found to be feasible, warranting further study in larger prospective trials.

Defining Breast Cryoablation Treatment Success: A Guide for the Curative and Palliative Treatment of Breast Cancer.

RATIONALE AND OBJECTIVES: Recent ICE3 trial of breast cryoablation for breast cancer demonstrated 98% success rate, similar to breast-conserving surgery. However, ICE3 and other published studies did not differentiate curative from palliative treatment nor define patient-specific treatment objectives. We sought to define treatment success of curative and palliative breast cryoablation for breast cancer in meeting procedure objectives and patient-specific treatment objectives. MATERIALS AND METHODS: We conducted a retrospective analysis of breast cancer patients who underwent breast cryoablation during 2021-2024. Breast radiologists performed outpatient cryoablation using local anesthesia and argon gas cryoprobes under ultrasound or MRI guidance. Patient demographics, referral indications, tumor characteristics, procedure details, and imaging follow-up findings were analyzed. Cryoablation was categorized as curative or palliative. Treatment success was defined as achievement of both procedure and patient-specific treatment objectives. RESULTS: Breast cryoablation was performed for 34 lesions in 29 patients with N0M0 (n = 25), N1M0 (n = 2), N2M0 (n = 1), and N0M1 (n = 1) disease. Most tumors were invasive ductal carcinoma (IDC), low to intermediate grade, estrogen receptor (ER) and progesterone receptor (PR) positive and HER2 negative (23 tumors, 68%). Tumor size ranged from 0.4-1.9 (median 0.8) cm for curative cryoablation and 0.6-6.0 (median 1.3) cm for palliative cryoablation. For 27 patients with follow-up imaging, ablation was curative in 14 patients, 14 tumors and palliative in 13 patients, 18 lesions. Imaging follow-up time ranged from 3 to 26 (median 16) months, > 12 months in 22 of 27 patients and 25 of 32 tumors. Complications were limited to 2 cases of skin frost injury, 1 mild and 1 moderate. Treatment success was achieved in 13 of 14 patients with curative and all 13 patients with palliative cryoablation. CONCLUSION: Our study defines treatment success for curative and palliative breast cryoablation, demonstrates breast cryoablation achieves not only procedure (technical) but also patient-specific treatment objectives without significant complications, and may serve as guide for integrating breast cryoablation in the treatment of breast cancer patients.

PRECISE: Preoperative Radiation Therapy to Elicit Critical Immune Stimulating Effects - A Phase 2 Clinical Trial.

PURPOSE: Radiation therapy is an underinvestigated tool for priming the immune system in intact human breast cancers. We sought here to investigate if a preoperative radiation therapy boost delivered was associated with a significant change in tumor-infiltrating lymphocytes (TILs) in the tumor in estrogen receptor positive, HER2Neu nonamplified breast cancers. METHODS AND MATERIALS: A total of 20 patients were enrolled in a phase 2 clinical trial and received either 7.5 Gy × 1 fraction or 2 Gy × 5 fractions, completed 6 to 8 days before surgery. Percent stromal TILs were evaluated on hematoxylin and eosin-stained samples. Short-term safety was assessed based on time to surgery, toxicities, and cosmesis up to 6 months after boost. RESULTS: Stromal TIL increased 6 to 8 days after completion of boost radiation therapy (median 3.0 [IQR, 1.0-6.5]) before radiation therapy versus median 5.0 (IQR, 1.5-8.0) after radiation therapy, P = .0037. Zero grade ≥3 toxicities up to 6 months after boost were experienced. In all, 94% (16/17) patients with 6-month follow-up cosmetic assessment after breast conservation had good-excellent cosmesis by physician assessment. CONCLUSION: In this phase 2 trial, preoperative radiation therapy boost resulted in a short-term increase in stromal TIL with minimal toxicities. Preoperative breast radiation therapy appears to be safe and may be a feasible means for priming the tumor microenvironment.

Clinical Outcomes for BRCA Pathogenic Variant Carriers With Breast Cancer Undergoing Breast Conservation.

Importance: Although most women with BRCA-associated breast cancer choose bilateral mastectomy, current guidelines support breast-conserving therapy as an option. As the indications for genetic testing expand and targeted therapies emerge, understanding the outcomes of breast-conserving therapy in the population of patients choosing breast conservation is important. Objective: To describe the clinical outcomes of women with BRCA-associated breast cancer who were treated with breast-conserving therapy, including the risks of ipsilateral and contralateral cancer events and bilateral mastectomy-free survival. Design, Setting, and Participants: This cohort study conducted at a single-institution academic national comprehensive cancer center included 172 women identified from a prospectively maintained database who had pathogenic BRCA1/2 variants and were treated with breast-conserving therapy from January 1, 1977, to December 31, 2021. Main Outcomes and Measures: Clinical and pathologic characteristics for patients with BRCA1 and BRCA2 were compared, and estimates of overall survival, bilateral mastectomy-free survival, distant disease-free survival, risk of ipsilateral breast cancer, and risk of contralateral cancer were computed. Results: The cohort included 172 women (mean [SD] age, 47.1 [11.7] years), with 42 (24.4%) receiving a diagnosis of breast cancer prior to 40 years of age. Compared with BRCA2 variant carriers (80 [46.5%]), women with BRCA1 variants (92 [53.5%]) were younger at breast cancer diagnosis and tended to have more advanced tumors, which were more likely to be hormone receptor negative and higher grade. At a median follow-up of 11.8 years (IQR, 5.7-18.2 years), estimates of 10-year survival and risk were: overall survival, 88.5% (95% CI, 83.1%-94.2%); bilateral mastectomy-free survival, 70.7% (95% CI, 63.3%-78.9%); risk of an ipsilateral breast cancer event, 12.2% (95% CI, 5.8%-18.2%); and risk of contralateral cancer, 21.3% (95% CI, 13.3%-28.6%). Risks continued to increase after 10 years of follow-up. Conclusions and Relevance: In this cohort study, although women with breast cancer and pathogenic BRCA1/2 variants treated with breast-conserving therapy had above-average risks of ipsilateral and contralateral breast cancer events, most did not have another cancer event and remained bilateral mastectomy free. These findings may be useful for informing patients with BRCA variants choosing breast conservation.

Disease Site Specialization in the Academic Radiation Oncology Workforce: Evidence of Gender Differences.

PURPOSE: Because some stakeholders within medicine seek to diversify and attain greater workforce equity, it is critical to understand gender-based divisions within specialization. Radiation oncology (RO) has one of the smallest proportions of women representation of all specialties, and to our knowledge, no prior studies have investigated gender differences in all the disease site specializations within RO. Thus, we analyzed the relationship between gender and disease site(s) treated in academic RO (ARO). METHODS AND MATERIALS: Faculty gender and disease site(s) treated by faculty from ARO departments were collected via publicly available department websites in January 2020. X2 analyses were conducted to assess differences between the proportions of women faculty treating each disease site. RESULTS: Of 1337 ARO faculty, 408 (30.5%) were identified as women. Breast, gynecology, and pediatrics had the largest proportions of women faculty (all >40%; P < .001). A majority (53%; P < .001) of women ARO faculty treated breast. Genitourinary, thoracic, and head and neck had the smallest proportions of women faculty (all <25%; P < .001). Women ARO faculty were twice as likely to treat breast and gynecologic malignancies compared with men faculty (risk ratio [RR] with 95% CI, 2.01 [1.75-2.50]; P < .001 and RR [95% CI], 2.06 [1.72-2.79]; P <.001, respectively). Men ARO faculty were 3 times more likely to treat genitourinary cancer compared with women faculty (RR [95% CI], 0.40 [0.34-0.48]; P < .001). There was no difference in the mean number of disease sites treated between women and men ARO faculty (2.63 vs 2.53; P = .29). CONCLUSIONS: Gender differences in disease site specialization were observed in ARO. Future research into the drivers of disease site selection should be explored.

Plasmonic nano-aperture label-free imaging of single small extracellular vesicles for cancer detection.

BACKGROUND: Small extracellular vesicle (sEV) analysis can potentially improve cancer detection and diagnostics. However, this potential has been constrained by insufficient sensitivity, dynamic range, and the need for complex labeling. METHODS: In this study, we demonstrate the combination of PANORAMA and fluorescence imaging for single sEV analysis. The co-acquisition of PANORAMA and fluorescence images enables label-free visualization, enumeration, size determination, and enables detection of cargo microRNAs (miRs). RESULTS: An increased sEV count is observed in human plasma samples from patients with cancer, regardless of cancer type. The cargo miR-21 provides molecular specificity within the same sEV population at the single unit level, which pinpoints the sEVs subset of cancer origin. Using cancer cells-implanted animals, cancer-specific sEVs from 20 µl of plasma can be detected before tumors were palpable. The level plateaus between 5-15 absolute sEV count (ASC) per µl with tumors ≥8 mm3. In healthy human individuals (N = 106), the levels are on average 1.5 ASC/µl (+/- 0.95) without miR-21 expression. However, for stage I-III cancer patients (N = 205), nearly all (204 out of 205) have levels exceeding 3.5 ASC/µl with an average of 12.2 ASC/µl (±9.6), and a variable proportion of miR-21 labeling among different tumor types with 100% cancer specificity. Using a threshold of 3.5 ASC/µl to test a separate sample set in a blinded fashion yields accurate classification of healthy individuals from cancer patients. CONCLUSIONS: Our techniques and findings can impact the understanding of cancer biology and the development of new cancer detection and diagnostic technologies.

Small extracellular vesicles (sEVs) are tiny particles derived from cells that can be detected in bodily fluids such as blood. Detecting sEVs and analyzing their contents may potentially help us to diagnose disease, for example by observing differences in sEV numbers or contents in the blood of patients with cancer versus healthy people. Here, we combine two imaging methods ­ our previously developed method PANORAMA and imaging of fluorescence emitted by sEVs­to visualize and count sEVs, determine their size, and analyze their cargo. We observe differences in sEV numbers and cargo in samples taken from healthy people versus people with cancer and are able to differentiate these two populations based on our analysis of sEVs. With further testing, our approach may be a useful tool for cancer diagnosis and provide insights into the biology of cancer and sEVs.

Neoadjuvant radioimmunotherapy synergy in triple-negative breast cancer: Is microenvironment-guided patient selection on the horizon?

Neoadjuvant chemotherapy plus immunotherapy for triple-negative breast cancer (TNBC) is associated with improved but incomplete response. In this issue of Cancer Cell, Shiao et al. characterize longitudinal biopsies from a window of opportunity study with single-cell RNA sequencing (scRNA-seq) and spatial proteomic profiling and elucidate synergy between radiotherapy (RT) and pembrolizumab.

Partial Breast Irradiation for Patients With Early-Stage Invasive Breast Cancer or Ductal Carcinoma In Situ: An ASTRO Clinical Practice Guideline.

PURPOSE: This guideline provides evidence-based recommendations on appropriate indications and techniques for partial breast irradiation (PBI) for patients with early-stage invasive breast cancer and ductal carcinoma in situ. METHODS: ASTRO convened a task force to address 4 key questions focused on the appropriate indications and techniques for PBI as an alternative to whole breast irradiation (WBI) to result in similar rates of ipsilateral breast recurrence (IBR) and toxicity outcomes. Also addressed were aspects related to the technical delivery of PBI, including dose-fractionation regimens, target volumes, and treatment parameters for different PBI techniques. The guideline is based on a systematic review provided by the Agency for Healthcare Research and Quality. Recommendations were created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength. RESULTS: PBI delivered using 3-dimensional conformal radiation therapy, intensity modulated radiation therapy, multicatheter brachytherapy, and single-entry brachytherapy results in similar IBR as WBI with long-term follow-up. Some patient characteristics and tumor features were underrepresented in the randomized controlled trials, making it difficult to fully define IBR risks for patients with these features. Appropriate dose-fractionation regimens, target volume delineation, and treatment planning parameters for delivery of PBI are outlined. Intraoperative radiation therapy alone is associated with a higher IBR rate compared with WBI. A daily or every-other-day external beam PBI regimen is preferred over twice-daily regimens due to late toxicity concerns. CONCLUSIONS: Based on published data, the ASTRO task force has proposed recommendations to inform best clinical practices on the use of PBI.

Patient Interest in Exploring Nonsurgical Treatment Approaches for Early-Stage Breast Cancer: A Qualitative Study.

PURPOSE: Advances in radiation therapy have enabled the ability to deliver ablative treatments, but there has been limited application of these treatments to early-stage breast cancers with a goal of omitting surgery. The purpose of this study was to explore patient interest in pursuing nonsurgical treatment approaches for their early-stage breast cancer. METHODS AND MATERIALS: We conducted a qualitative study involving interviews with 21 patients with early-stage breast cancer who were eligible for participation in a phase 2 clinical trial offering omission of definitive surgery. Interviews were transcribed and an inductive, thematic analysis was performed by 3 independent reviewers to generate themes and subthemes. RESULTS: Data analysis revealed the following factors that affected patient willingness and desire to explore nonsurgical treatment options: (1) perceptions and feelings about their cancer; (2) current quality of life and the level of support available in their daily life; (3) external conversations focusing on family members' and friends' experiences with cancer and/or cancer treatments; (4) personal health care experiences, including their current breast cancer diagnosis; (5) perceptions and feelings about their physicians; (6) conversations with their physicians about their treatment options; and (7) self-identified desire to direct care decisions. Specifically, patients verbalized fearing surgery and surgical recovery; wanting to preserve their breast(s); the prior negative surgical experiences of friends, family, and themselves; a desire to receive treatment per the latest research; wanting to match the level of treatment with the severity of their cancer; and other comorbidities as reasons for wanting to explore omitting surgery. CONCLUSIONS: Our findings demonstrate an unmet need directed by patient interest to explore nonsurgical options for early-stage, biologically favorable breast cancer. These results may shape conversations around shared decision-making and clinical trial design, and result in more personalized treatment options for women with early-stage breast cancer.

Association Between Symptom Burden and Early Lymphatic Abnormalities After Regional Nodal Irradiation for Breast Cancer.

PURPOSE: Dermal backflow visualized on near-infrared fluorescence lymphatic imaging (NIRF-LI) signals preclinical lymphedema that precedes the development of volumetrically defined lymphedema. We sought to evaluate whether dermal backflow correlates with patient-reported lymphedema outcomes (PRLO) surveys in breast cancer patients treated with regional nodal irradiation (RNI). METHODS AND MATERIALS: Patients with breast cancer planned for axillary dissection and RNI prospectively underwent perometry, NIRF-LI, and PRLOs (the Lymphedema Symptom Intensity and Distress Survey [LSIDS] and QuickDASH) at baseline, after surgery, and at 6, 12, and 18 months after radiation. Clinical lymphedema was defined as an arm volume increase ≥5% over baseline. Trends over time were assessed using analysis of variance testing. The association between survey responses and both dermal backflow and lymphedema was assessed using a linear mixed-effects model. RESULTS: Sixty participants completed at least 2 sets of measurements and surveys and were eligible for analysis. Fifty-four percent of patients had cT3-T4 disease, 53% cN3 disease, and 75% had a body mass index >25. Dermal backflow and clinical lymphedema increased from 10% to 85% and from 0% to 40%, respectively, from baseline to 18 months. In the adjusted model, soft tissue sensation, neurologic sensation, and functional LSIDS subscale scores were associated with presence of dermal backflow (all P < .05). Both dermal backflow and lymphedema were associated with QuickDASH score (P < .05). CONCLUSIONS: In this high-risk cohort, we found highly prevalent early signs of lymphedema, with increased symptom burden from baseline. Presence of dermal backflow correlated with PRLO measures, highlighting a potential NIRF-LI use to identify patients for early intervention trials after RNI.

Patient-Reported Outcomes of Omission of Breast Surgery Following Neoadjuvant Systemic Therapy: A Nonrandomized Clinical Trial.

Importance: Patients should have an active role in decisions about pursuing or forgoing specific therapies in treatment de-escalation trials. Objective: To evaluate longitudinal patient-reported outcomes (PROs) encompassing decisional comfort and health-related quality of life (HRQOL) among patients who elected to enroll in a clinical trial evaluating radiotherapy alone, without breast surgery, for invasive breast cancers with exceptional response to neoadjuvant systemic therapy (NST). Design, Setting, and Participants: Prospective, single-group, phase 2 clinical trial at 7 US medical centers. Women aged 40 years or older with invasive cT1-2 N0-1 M0 triple-negative or human epidermal growth factor receptor 2 (ERBB2)-positive breast cancer with no pathologic evidence of residual disease following standard NST enrolled from March 6, 2017, to November 9, 2021. Validated PRO measures were administered at baseline and 6, 12, and 36 months post-radiotherapy. Data were analyzed from January to February 2023. Interventions: PRO measures included the Decision Regret Scale (DRS), Functional Assessment of Cancer Therapy-Lymphedema (FACT-B+4), and Breast Cancer Treatment Outcomes Scale (BCTOS). Main Outcomes and Measures: Changes in PRO measure scores and subscores over time. Results: Among 31 patients, the median (IQR) age was 61 (56-66) years, 26 (84%) were White, and 26 (84%) were non-Hispanic. A total of 15 (48%) had triple-negative disease and 16 (52%) had ERBB2-positive disease. Decisional comfort was high at baseline (median [IQR] DRS score 10 [0-25] on a 0-100 scale, with higher scores indicating higher decisional regret) and significantly increased over time (median [IQR] DRS score at 36 months, 0 [0-20]; P < .001). HRQOL was relatively high at baseline (median [IQR] FACT-B composite score 121 [111-134] on a 0-148 scale, with higher scores indicating higher HRQOL) and significantly increased over time (median [IQR] FACT-B score at 36 months, 128 [116-137]; P = .04). Perceived differences between the affected breast and contralateral breast were minimal at baseline (median [IQR] BCTOS score 1.05 [1.00-1.23] on a 1-4 scale, with higher scores indicating greater differences) and increased significantly over time (median [IQR] BCTOS score at 36 months, 1.36 [1.18-1.64]; P < .001). At 36 months postradiotherapy, the cosmetic subscore was 0.45 points higher than baseline (95% CI, 0.16-0.74; P = .001), whereas function, pain, and edema subscores were not significantly different than baseline. Conclusions and Relevance: In this nonrandomized phase 2 clinical trial, analysis of PROs demonstrated an overall positive experience for trial participants, with longitudinal improvements in decisional comfort and overall HRQOL over time and minimal lasting adverse effects of therapy. Trial Registration: ClinicalTrials.gov Identifier: NCT02945579.

Automated contouring and statistical process control for plan quality in a breast clinical trial.

Background and purpose: Automatic review of breast plan quality for clinical trials is time-consuming and has some unique challenges due to the lack of target contours for some planning techniques. We propose using an auto-contouring model and statistical process control to independently assess planning consistency in retrospective data from a breast radiotherapy clinical trial. Materials and methods: A deep learning auto-contouring model was created and tested quantitatively and qualitatively on 104 post-lumpectomy patients' computed tomography images (nnUNet; train/test: 80/20). The auto-contouring model was then applied to 127 patients enrolled in a clinical trial. Statistical process control was used to assess the consistency of the mean dose to auto-contours between plans and treatment modalities by setting control limits within three standard deviations of the data's mean. Two physicians reviewed plans outside the limits for possible planning inconsistencies. Results: Mean Dice similarity coefficients comparing manual and auto-contours was above 0.7 for breast clinical target volume, supraclavicular and internal mammary nodes. Two radiation oncologists scored 95% of contours as clinically acceptable. The mean dose in the clinical trial plans was more variable for lymph node auto-contours than for breast, with a narrower distribution for volumetric modulated arc therapy than for 3D conformal treatment, requiring distinct control limits. Five plans (5%) were flagged and reviewed by physicians: one required editing, two had clinically acceptable variations in planning, and two had poor auto-contouring. Conclusions: An automated contouring model in a statistical process control framework was appropriate for assessing planning consistency in a breast radiotherapy clinical trial.

Prospective, early longitudinal assessment of lymphedema-related quality of life among patients with locally advanced breast cancer: The foundation for building a patient-centered screening program.

BACKGROUND: We examined how breast cancer-related lymphedema (BCRL) affects health-related quality of life (HRQOL), productivity, and compliance with therapeutic interventions to guide structuring BCRL screening programs. METHODS: We prospectively followed consecutive breast cancer patients who underwent axillary lymph node dissection (ALND) with arm volume screening and measures assessing patient-reported health-related quality of life (HRQOL) and perceptions of BCRL care. Comparisons by BCRL status were made with Mann-Whitney U, Chi-square, Fisher's exact, or t tests. Trends over time from ALND were assessed with linear mixed-effects models. RESULTS: With a median follow-up of 8 months in 247 patients, 46% self-reported ever having BCRL, a proportion that increased over time. About 73% reported fear of BCRL, which was stable over time. Further in time from ALND, patients were more likely to report that BCRL screening reduced fear. Patient-reported BCRL was associated with higher soft tissue sensation intensity, biobehavioral, and resource concerns, absenteeism, and work/activity impairment. Objectively measured BCRL had fewer associations with outcomes. Most patients reported performing prevention exercises, but compliance decreased over time; patient-reported BCRL was not associated with exercise frequency. Fear of BCRL was positively associated with performing prevention exercises and using compressive garments. CONCLUSIONS: Both incidence and fear of BCRL were high after ALND for breast cancer. Fear was associated with improved therapeutic compliance, but compliance decreased over time. Patient-reported BCRL was more strongly associated with worse HRQOL and productivity than was objective BCRL. Screening programs must support patients' psychological needs and aim to sustain long-term compliance with recommended interventions.

Effectiveness Without Efficacy: Cautionary Tale from a Landmark Breast Cancer Randomized Controlled Trial.

Background: "Old" randomized controlled trials established breast conserving therapy (BCT) and total mastectomy (TM) equivalence for treating early breast cancer, whereas recent literature report improved survival with BCT. To reconcile this, we performed a simulation study and re-analyzed B-06 trial data. Methods: We estimated the distributions for overall survival (OS), cumulative incidence functions for breast-cancer-specific death (BCSD) and other causes-specific death (OCSD) by BCT and TM. The restricted mean survival time (RMST) difference and hazard ratio between the two arms were estimated. Given the estimated distributions, we simulated cause-specific death times from each arm, evaluating the power to test treatment difference in OS, BCSD, and OCSD with different sample sizes, follow-up times, and a modified setting by simulating BCT-arm OCSD times from the distribution of patients not receiving radiation. Results: With 200 months follow-up, the average BCT-over-TM gain measured by RMST was 3.7 months for OS and 4.5 months for BCSD. Increasing the trial size to 5,000 per arm, there is a 79.2% chance to detect the OS benefit with RMST and 92.4% for BCSD. A nonproportional increase of OCSD in BCT compared to TM was observed after 144 months, and particularly after 200 months post treatments. When OCSD times of BCT were simulated using patients not receiving radiation, the estimated OS gain increased to 4.4 months, and the power increased to 92.2%. Conclusions: The late excess other-cause-death, likely due to radiation, in the BCT arm and sample size constraints limited the power to report BCT superiority. Given radiation delivered in the era of B-06 trial, BCT and TM remain largely equivalent.

Socioeconomic Barriers to Randomized Clinical Trial Retention in Patients Treated With Adjuvant Radiation for Early-Stage Breast Cancer.

PURPOSE: Socioeconomic barriers contribute to breast cancer clinical trial enrollment disparities. We sought to identify whether socioeconomic disadvantage also is associated with decreased trial retention. METHODS AND MATERIALS: We performed a secondary analysis of 253 (of 287) patients enrolled in a randomized phase 3 trial of conventionally fractionated versus hypofractionated whole-breast irradiation. The outcome of trial retention versus dropout was defined primarily based on whether the patient completed breast cosmesis outcomes assessment at 3-year follow-up, and secondarily, at 5-year follow-up. Associations of retention with severity of socioeconomic disadvantage, quantified by patients' home neighborhood area deprivation index (ADI) rank (1 [least] to 100 [most deprivation]), were tested using the Kruskal-Wallis test and multivariate logistic regression. Associations of retention with patients' use of social resource assistance were analyzed using the χ2 test. RESULTS: In total, 21.7% (n = 55) of patients dropped out by 3 years and 36.7% (n = 92) by 5 years. Median ADI was 36.5 (interquartile range, 22-57) for retained and 46.0 (interquartile range, 29-60) for dropout patients. Dropout was associated with more severe socioeconomic deprivation (ADI ≥45 vs <45) at 3 years (odds ratio, 3.63; 95% confidence interval, 1.62-8.15; P = .002) and 5 years (odds ratio, 2.55; 95% confidence interval, 1.37-4.76; P = .003). While on study, patients who ultimately dropped out were more likely to require resource assistance for practical (transportation, housing, financial) than psychological needs (distress, grief) or advance care planning (P = .03). CONCLUSIONS: In this study, ADI was associated with disparities in clinical trial retention of patients with breast cancer receiving adjuvant radiation treatment. Results suggest that developing multidimensional interventions that extend beyond routine social determinants needs screening are needed, not only to enhance initial clinical trial access and enrollment but also to enable robust long-term retention of socioeconomically disadvantaged patients and improve the validity and generalizability of reported long-term trial clinical and patient-reported outcomes.

Plasma Cytokines/Chemokines as Predictive Biomarkers for Lymphedema in Breast Cancer Patients.

Breast cancer-related lymphedema (BCRL) occurs in ~ 40% of patients after axillary lymph node dissection (ALND), radiation therapy (RT), or chemotherapy. First-line palliative treatment utilizes compression garments and specialized massage. Reparative microsurgeries have emerged as a second-line treatment, yet both compression and surgical therapy are most effective at early stages of LE development. Identifying patients at the highest risk for BCRL would allow earlier, more effective treatment. Perometric arm volume measurements, near-infrared fluorescent lymphatic imaging (NIRF-LI) data, and blood were collected between 2016 and 2021 for 40 study subjects undergoing treatment for breast cancer. Plasma samples were evaluated using MILLIPLEX human cytokine/chemokine panels at pre-ALND and at 12 months post-RT. A Mann-Whitney t-test showed that G-CSF, GM-CSF, IFN-2α, IL-10, IL-12p40, IL-15, IL-17A, IL-1ß, IL-2, IL-3, IL-6, and MIP-1ß were significantly higher at pre-ALND in those presenting with BCRL at 12 months post-RT. MIP-1ß and IL-6 were significantly higher at pre-ALND in those who developed dermal backflow, but no BCRL, at 12 months post-RT. Plasma IL-15, IL-3, and MIP-1ß were elevated at 12 months after RT in those with clinical BCRL. These findings establish BCRL as a perpetual inflammatory disorder, and suggest the use of plasma cytokine/chemokine levels to predict those at highest risk.