Helping ourselves, helping others: the Young Women's Breast Cancer Study (YWS) - a multisite prospective cohort study to advance the understanding of breast cancer diagnosed in women aged 40 years and younger.

PURPOSE: Compared with older women diagnosed with breast cancer, younger women are more likely to die of breast cancer and more likely to suffer psychosocially in both the short-term and long term. The Young Women's Breast Cancer Study (YWS) is a multisite prospective cohort study established to address gaps in our knowledge about this vulnerable and understudied population. PARTICIPANTS: The YWS enrolled 1302 women newly diagnosed with stages 0-IV breast cancer at age 40 years or younger at 13 academic and community sites in North America between 2006 and 2016. Longitudinal patient-reported outcome data are complemented by clinical data abstraction and biospecimen collection at multiple timepoints. FINDINGS TO DATE: Key findings related to fertility include that nearly 40% of participants were interested in pregnancy following diagnosis; of those who reported interest, 10% pursued fertility preservation. Overall, approximately 10% of YWS participants became pregnant in the first 5 years after diagnosis; follow-up is ongoing for pregnancies after 5 years. Studies focused on psychosocial outcomes have characterised quality of life, post-traumatic stress and fear of recurrence, with findings detailing the factors associated with the substantial psychosocial burden many young women face during and following active treatment. Multiple studies have leveraged YWS biospecimens, including whole-exome sequencing of tumour analyses that revealed that select somatic alterations occur at different frequencies in young (age≤35) versus older women with luminal A breast cancer, and a study that explored clonal hematopoiesis of indeterminate potential found it to be rare in young survivors. FUTURE PLANS: With a median follow-up of approximately 10 years, the cohort is just maturing for many relevant long-term outcomes and provides outstanding opportunities to further study and build collaborations to address gaps in our knowledge, with the ultimate objective to improve care and outcomes for young women with breast cancer. TRIAL REGISTRATION NUMBER: NCT01468246.

Factors influencing 5-year persistence to adjuvant endocrine therapy in young women with breast cancer.

PURPOSE: Although younger age has been negatively associated with persistence to adjuvant endocrine therapy (ET), factors contributing to non-persistence remain poorly understood. We assessed factors associated with non-persistence to ET and described the 5-year trajectories of quality of life (QoL) and symptoms in young women (≤40 years) with hormone receptor-positive breast cancer (BC). METHODS: We retrieved data on clinical characteristics and non-persistence from the medical annual records in the European cohort of the "Helping Ourselves, Helping Others: The Young Women's BC Study" (IBCSG 43-09 HOHO). Women completed surveys at baseline, biannually for three years, and annually for another seven years. Data collection included sociodemographic information, QoL aspects assessed by the Cancer Rehabilitation Evaluation System-Short Form and symptoms assessed by the Breast Cancer Prevention Trial symptom scales. Cox regression models were applied to identify factors associated with non-persistence. RESULTS: The cumulative risk of interrupting ET within 5 years was 27.7 % (95 % CI, 21.5-35.2). The QoL subscale scores remained stable over 5 years, with slight improvements in the physical subscale. Hot flashes decreased (p < 0.001), while vaginal problems intensified (p < 0.001) over time. Being married without children and having difficulties interacting and communicating with the medical team were significantly associated with non-persistence. CONCLUSIONS: Discussing the desire to conceive with partnered childless women and establishing a good relationship with the medical team may be important in addressing the non-persistence in young BC survivors. As recent data suggests the safety of pausing ET to conceive, this approach may be a reasonable future option to limit non-persistence.

Association of cancer treatment with excess heart age among five-year young breast cancer survivors.

PURPOSE: Data evaluating cardiovascular disease (CVD) risk by cancer treatment among young women (≤ 40 years) with breast cancer are limited. METHODS: Among 372 five-year breast cancer survivors aged 30-40 years from the Young Women's Breast Cancer Study, we assessed the association of cancer treatments (anthracyclines, trastuzumab, radiation/laterality, endocrine therapy) and excess heart age (difference between predicted 10-year CVD risk as assessed by adapted Framingham Risk Score and chronological age), prevalent elevated excess heart age (≥ 2 years), and worsening excess heart age (change of ≥ 2 excess heart age years) at breast cancer diagnosis and two- and five-year follow-up using multivariable linear and logistic regressions. RESULTS: Most women had stage I or II (79%), ER + (71%), or PR + (65%) breast cancer. At diagnosis, women had little excess heart age by treatment receipt (range of means = -0.52,0.91 years). Left-sided radiation (ß = 2.49,SE = 0.96,p = 0.01) was associated with higher excess heart age at five-year follow-up. For prevalent elevated excess heart age (two-year = 26%;five-year = 27%), women treated with right-sided radiation had increased risk at two-years (OR = 2.17,95%CI = 1.12-4.19), yet at five-years, associations were observed after any radiation (OR = 1.92,95%CI = 1.09-3.41), especially after left-sided (OR = 2.13,95%CI = 1.09-3.41) radiation. No associations were observed between systemic treatments and prevalent elevated excess heart age or any treatments with worsening excess heart age. CONCLUSIONS: Among young breast cancer survivors, radiation, but not other cancer treatments, was associated with elevated excess heart age. IMPLICATIONS FOR CANCER SURVIVORS: CVD risk tools that incorporate cancer treatment, such as radiation, are needed to identify high risk young breast cancer survivors given the long survivorship and long latency of cardiovascular disease.

Adjuvant Trastuzumab Emtansine Versus Paclitaxel Plus Trastuzumab for Stage I Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: 5-Year Results and Correlative Analyses From ATEMPT.

PURPOSE: Long-term outcomes of patients with stage I human epidermal growth factor receptor 2 (HER2)-positive breast cancer receiving adjuvant trastuzumab emtansine (T-DM1) remain undefined, and prognostic predictors represent an unmet need. METHODS: In the ATEMPT phase II trial, patients with stage I centrally confirmed HER2-positive breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for 1 year or paclitaxel plus trastuzumab (TH). Coprimary objectives were to compare the incidence of clinically relevant toxicities between arms and to evaluate invasive disease-free survival (iDFS) with T-DM1. Correlative analyses included the HER2DX genomic tool, multiomic evaluations of HER2 heterogeneity, and predictors of thrombocytopenia. RESULTS: After a median follow-up of 5.8 years, 11 iDFS events were observed in the T-DM1 arm, consistent with a 5-year iDFS of 97.0% (95% CI, 95.2 to 98.7). At 5 years, the recurrence-free interval (RFI) was 98.3% (95% CI, 97.0 to 99.7), the overall survival was 97.8% (95% CI, 96.3 to 99.3), and the breast cancer-specific survival was 99.4% (95% CI, 98.6 to 100). Comparable iDFS was observed with T-DM1 irrespective of tumor size, hormone receptor status, centrally determined HER2 immunohistochemical score, and receipt of T-DM1 for more or less than 6 months. Although ATEMPT was not powered for this end point, the 5-year iDFS in the TH arm was 91.1%. Among patients with sufficient tissue for HER2DX testing (n = 187), 5-year outcomes significantly differed according to HER2DX risk score, with better RFI (98.1% v 81.8%, hazard ratio [HR], 0.10, P = .01) and iDFS (96.3% v 81.8%, HR, 0.20, P = .047) among patients with HER2DX low-risk versus high-risk tumors, respectively. CONCLUSION: Adjuvant T-DM1 for 1 year leads to outstanding long-term outcomes for patients with stage I HER2-positive breast cancer. A high HER2DX risk score predicted a higher risk of recurrence in ATEMPT.

OptimICE-RD: sacituzumab govitecan + pembrolizumab vs pembrolizumab (± capecitabine) for residual triple-negative breast cancer.

Patients with early-stage triple-negative breast cancer (TNBC) with residual invasive disease after neoadjuvant therapy have a high risk of recurrence even with neoadjuvant and adjuvant treatment with pembrolizumab. Sacituzumab govitecan, a Trop-2-directed antibody-drug conjugate with a topoisomerase I inhibitor payload, improved progression-free survival (PFS) and overall survival (OS) versus chemotherapy in patients with pre-treated metastatic TNBC. Moreover, preclinical data suggest that topoisomerase I inhibitors may enhance the effects of immune checkpoint inhibitors through activation of the cGAS-STING pathway. Here we describe the international randomized phase III AFT-65/ASCENT-05/OptimICE-RD trial, which evaluates the efficacy and safety of sacituzumab govitecan plus pembrolizumab versus treatment of physician's choice (pembrolizumab ± capecitabine) among patients with early-stage TNBC with residual invasive disease after neoadjuvant therapy.Clinical Trial Registration: NCT05633654 (ClinicalTrials.gov)Other Study ID Number(s): Gilead Study ID: GS-US-595-6184Registration date: 1 December 2022Study start date: 12 December 2022Recruitment status: Recruiting.

AFT-65/ASCENT-05/OptimICE-RD is an ongoing clinical trial that is testing a new treatment combination for patients with stage II or III triple-negative breast cancer (TNBC). Stage II­III means the cancer is confined to the breast and/or nearby lymph nodes and can be surgically removed. However, there remains a risk that the cancer could recur after surgery. To reduce this risk, patients with stage II­III TNBC receive anti-cancer medication before and after surgery. For some patients, receipt of anti-cancer medication before surgery produces a pathologic complete response (pCR), meaning there is no observable cancer left behind at surgery. Patients with a pCR have a lower risk of recurrence than patients with residual disease.The AFT-65/ASCENT-05/OptimICE-RD trial includes people with stage II-III TNBC who have residual cancer after completing their course of pre-surgery anti-cancer medication. All participants have any remaining cancer in their breast and/or lymph nodes removed surgically, after which they are randomly assigned to receive one of two treatments. The experimental therapy consists of pembrolizumab along with a medication called sacituzumab govitecan, which kills cancer cells directly and may strengthen the anti-cancer immune response. Pembrolizumab strengthens the anti-cancer immune response, so the hypothesis of this trial is that the two medications will be more effective together. The control therapy consists of pembrolizumab, alone or in combination with a chemotherapy medication called capecitabine, which is the current standard of care. To study the effectiveness of each treatment, the researchers are following up with all participants to learn if and when their breast cancer returns.

Palbociclib in adults aged 70 years and older with advanced breast cancer: A phase 2 multicenter trial (Alliance A171601).

INTRODUCTION: Palbociclib is a widely used treatment for advanced breast cancer in older adults. However, the existing evidence regarding its safety and tolerability in this age group is inconsistent and limited to retrospective subgroup or pooled analyses. MATERIALS AND METHODS: We conducted a prospective single-arm multicenter phase 2 study to evaluate the safety and tolerability of palbociclib in participants aged 70 years or older with advanced hormone receptor-positive breast cancer. Participants were given palbociclib in combination with their physician's choice of endocrine therapy (letrozole or fulvestrant). The primary endpoint was the incidence of grade 3+ adverse events (AEs) by six months. Secondary endpoints included AE-related dose delays, dose reductions, early discontinuations, and hospitalizations. Additionally, we compared these endpoints by age groups (70-74 and ≥ 75 years). RESULTS: Of the 90 participants (median age 74 years [70-87]) enrolled, 75.6% (95% confidence interval [CI], 65.4-84.0) had grade 3+ AEs by six months. The most frequent grade 3+ AEs were neutropenia (61%), fatigue (4%), and nausea (3%). Febrile neutropenia was uncommon (1.1%). Due to AEs, 36% had dose delays, 34% had dose reductions, 10% had early discontinuations, and 10% had hospitalizations. Compared to those aged 70-74 years, participants aged ≥75 years had higher rates of early discontinuations (5.9% vs 15.9%, a difference of 9.5% [95% CI 3.5%-22.5%]). DISCUSSION: Palbociclib has an overall favorable safety profile in adults aged ≥70 with advanced breast cancer. However, adults ≥75 years had a trend toward higher rates of AE-related early discontinuations compared to those 70-74 years. Further research is needed to evaluate tolerability and improve the delivery of palbociclib in older adults. CLINICALTRIALS: gov:NCT03633331.

Validation of the AJCC 8th Edition Breast Cancer Prognostic Staging System in Legacy Alliance Trials (AFT-01).

BACKGROUND: The 8th edition American Joint Committee on Cancer staging system combined anatomic stage (AS) with receptor status and grade to create prognostic stage (PS). PS has been validated in single-institution and cancer registry studies; however, missing human epidermal growth factor receptor 2 (HER2) status and variable treatment and follow-up create limitations. OBJECTIVE: Our objective was to compare the relative prognostic ability of PS versus AS to predict survival using breast cancer clinical trial data. METHODS: Women with non-metastatic breast cancer enrolled in six Alliance for Clinical Trials in Oncology trials were included (enrollment years 1997-2010). AS and PS were constructed using pathological tumor size, nodal status, estrogen receptor (ER), progesterone receptor (PR), HER2 status, and grade. Unadjusted Cox proportional hazard models were estimated to predict overall survival within 5 years, with AS and PS as predictor variables. The relative predictive power of staging models was assessed by comparing Harrell concordance indices (C-indices). Kaplan-Meier-based mortality estimates were compared by stage. RESULTS: Overall, 6924 women were included (median age 53 years); 45.2% were diagnosed with ER+/PR+/HER2- tumors, 26.2% with HER2+ tumors, and 17.1% with ER-/PR-/HER2- tumors. Median follow-up time was 5 years (interquartile range 2.95-5.00). PS significantly improved predictive performance (C-index 0.721) for overall survival compared with AS (0.700) (p = 0.020). Kaplan-Meier hazard estimates suggested PS did not distinguish mortality risk between patients with IIB and IIIA or IB and IIA disease. CONCLUSIONS: PS has significantly improved predictive performance for OS compared with AS. As systemic therapies evolve, it will be important to re-evaluate the prognostic staging system, particularly for patients with intermediate-stage cancers. CLINICALTRIALS: gov Identifier: NCT02171078.

6th and 7th International consensus guidelines for the management of advanced breast cancer (ABC guidelines 6 and 7).

This manuscript describes the Advanced Breast Cancer (ABC) international consensus guidelines updated at the last two ABC international consensus conferences (ABC 6 in 2021, virtual, and ABC 7 in 2023, in Lisbon, Portugal), organized by the ABC Global Alliance. It provides the main recommendations on how to best manage patients with advanced breast cancer (inoperable locally advanced or metastatic), of all breast cancer subtypes, as well as palliative and supportive care. These guidelines are based on available evidence or on expert opinion when a higher level of evidence is lacking. Each guideline is accompanied by the level of evidence (LoE), grade of recommendation (GoR) and percentage of consensus reached at the consensus conferences. Updated diagnostic and treatment algorithms are also provided. The guidelines represent the best management options for patients living with ABC globally, assuming accessibility to all available therapies. Their adaptation (i.e. resource-stratified guidelines) is often needed in settings where access to care is limited.

Moderators of Intervention Efficacy in the Pathways to Wellness Trial of Survivorship Education and Mindfulness Meditation for Younger Breast Cancer Survivors.

PURPOSE: Depression is associated with poor outcomes in breast cancer survivors (BCSs), with higher prevalence among younger women. The Pathways to Wellness (PTW; ClinicalTrials.gov identifier: NCT03025139) randomized controlled trial (RCT) demonstrated beneficial effects of two behavioral interventions (survivorship education [SE] and mindful awareness practices [MAPs]) on depressive symptoms in younger BCS. We conducted an exploratory secondary analysis to identify moderators of intervention effects. METHODS: Women diagnosed with stage 0 to III breast cancer at or before age 50 years who completed cancer treatment were randomly assigned to 6 weeks of SE (n = 81), MAPs (n = 85), or waitlist control (WLC; n = 81). Moderators assessed at baseline included psychological distress (depression and anxiety), intervention preference, preparedness for survivorship, and time since initial diagnosis. Linear regression models tested the modifying effects of each variable on postintervention depression in SE versus WLC and MAPs versus WLC. RESULTS: Baseline levels of depression (ß = -.03, P < .01) and anxiety (ß = -.64, P = .02) moderated effects of SE on depressive symptoms, as did preparedness for survivorship (ß = 3.17, P = .02). Participants randomly assigned to SE who had the highest levels of depression or anxiety and who felt least prepared for survivorship showed the largest reductions in depressive symptoms from preintervention to postintervention. Similar effects were not observed for MAPs. Intervention preference and time since diagnosis did not moderate intervention effects for either SE or MAPs. CONCLUSION: Our 6-week, group-based SE program may be most beneficial for women with higher levels of psychological distress and those who feel least prepared for cancer survivorship. By contrast, a 6-week mindfulness awareness practice intervention appears to benefit younger BCS regardless of pretreatment characteristics.

Second primary non-breast cancers in young breast cancer survivors.

PURPOSE: We evaluated the incidence, timing, and risk factors for second primary non-breast cancers (SPNBC) among young breast cancer (BC) survivors. METHODS: This study included participants of the Young Women's BC Study (YWS) who were diagnosed with stage 0-III BC between 2006 and 2016 and age 40 or younger at diagnosis (N = 1,230). Patient characteristics, treatment information, and clinical events were collected via serial surveys. Tumor and treatment data were obtained from medical record review. Five- and 10-year risks of SPNBCs were estimated via the cumulative incidence function, considering death, metastasis, or second primary BC as competing events. Fine and Gray subdistribution hazard models estimated subdistribution hazard ratios (sHRs) and 95% confidence intervals (CI) for SPNBC risk based on risk factors including demographics, germline genetics, primary BC characteristics, and treatments. RESULTS: Among 1,230 women, over a median follow-up of 10.1 years, 47 patients (4%) developed an SPNBC. Types of malignancy included melanoma (n = 10), thyroid (n = 10), ovarian (n = 4), sarcoma (n = 4), uterine (n = 3), rectal (n = 3), bladder (n = 2), cervical (n = 2), head/neck (n = 2), lung (n = 2), lymphoma (n = 2), pancreatic (n = 2), and renal (n = 1). Five and 10-year cumulative incidence were 1.4% and 3.2%, respectively. Median time between primary BC and SPNBC was 7.3 years. No patient factors, primary tumor characteristics, or treatments were statistically significantly associated with SPNBC in univariable or multivariable models. CONCLUSION: In this population, five-year cumulative incidence was higher than that reported among healthy women under 50 years of age, highlighting the importance of long-term surveillance for new non-breast cancers in young adult BC survivors.

Antibody-Drug Conjugate Sacituzumab Govitecan Enables a Sequential TOP1/PARP Inhibitor Therapy Strategy in Patients with Breast Cancer.

PURPOSE: The antibody-drug conjugate (ADC) sacituzumab govitecan (SG) comprises the topoisomerase 1 (TOP1) inhibitor (TOP1i) SN-38, coupled to a monoclonal antibody targeting trophoblast cell surface antigen 2 (TROP-2). Poly(ADP-ribose) polymerase (PARP) inhibition may synergize with TOP1i and SG, but previous studies combining systemic PARP and TOP1 inhibitors failed due to dose-limiting myelosuppression. Here, we assess the proof-of-mechanism and clinical feasibility for SG and talazoparib (TZP) employing an innovative sequential dosing schedule. PATIENTS AND METHODS: In vitro models tested pharmacodynamic endpoints, and in a phase 1b clinical trial (NCT04039230), 30 patients with metastatic triple-negative breast cancer (mTNBC) received SG and TZP in a concurrent (N = 7) or sequential (N = 23) schedule. Outcome measures included safety, tolerability, preliminary efficacy, and establishment of a recommended phase 2 dose. RESULTS: We hypothesized that tumor-selective delivery of TOP1i via SG would reduce nontumor toxicity and create a temporal window, enabling sequential dosing of SG and PARP inhibition. In vitro, sequential SG followed by TZP delayed TOP1 cleavage complex clearance, increased DNA damage, and promoted apoptosis. In the clinical trial, sequential SG/TZP successfully met primary objectives and demonstrated median progression-free survival (PFS) of 7.6 months without dose-limiting toxicities (DLT), while concurrent dosing yielded 2.3 months PFS and multiple DLTs including severe myelosuppression. CONCLUSIONS: While SG dosed concurrently with TZP is not tolerated clinically due to an insufficient therapeutic window, sequential dosing of SG followed by TZP proved a viable strategy. These findings support further clinical development of the combination and suggest that ADC-based therapy may facilitate novel, mechanism-based dosing strategies.

Fertility Preservation and Assisted Reproduction in Patients With Breast Cancer Interrupting Adjuvant Endocrine Therapy to Attempt Pregnancy.

PURPOSE: We investigated time to pregnancy, efficacy and safety of fertility preservation, and assisted reproductive technologies (ARTs) in women with early hormone receptor-positive breast cancer (BC) desiring future pregnancy. PATIENTS AND METHODS: POSITIVE is an international, single-arm, prospective trial, in which 518 women temporarily interrupted adjuvant endocrine therapy to attempt pregnancy. We evaluated menstruation recovery and factors associated with time to pregnancy and investigated if ART use was associated with achieving pregnancy. The cumulative incidence of BC-free interval (BCFI) events was estimated according to the use of ovarian stimulation at diagnosis. The median follow-up was 41 months. RESULTS: Two hundred seventy-three patients (53%) reported amenorrhea at enrollment, of whom 94% resumed menses within 12 months. Among 497 patients evaluable for pregnancy, 368 (74%) reported at least one pregnancy. Young age was the main factor associated with shorter time to pregnancy with cumulative incidences of pregnancy by 1 year of 63.5%, 54.3%, and 37.7% for patients age <35, 35-39, and 40-42 years, respectively. One hundred and seventy-nine patients (36%) had embryo/oocyte cryopreservation at diagnosis, of whom 68 reported embryo transfer after enrollment. Cryopreserved embryo transfer was the only ART associated with higher chance of pregnancy (odds ratio, 2.41 [95% CI, 1.75 to 4.95]). The cumulative incidence of BCFI events at 3 years was similar for women who underwent ovarian stimulation for cryopreservation at diagnosis, 9.7% (95% CI, 6.0 to 15.4), compared with those who did not, 8.7% (95% CI, 6.0 to 12.5). CONCLUSION: In POSITIVE, fertility preservation using ovarian stimulation was not associated with short-term detrimental impact on cancer prognosis. Pregnancy rates were highest among those who underwent embryo/oocyte cryopreservation followed by embryo transfer.

Psychosocial and supportive care concerns of young women living with advanced breast cancer: baseline findings from a prospective virtual support intervention study.

PURPOSE: Adolescent and young adults (AYAs) with metastatic breast cancer (MBC) experience high physical and psychosocial burdens compounded by a disrupted life trajectory. We sought to determine the psychosocial and supportive care concerns of this population to better understand and address unmet needs. METHODS: AYAs diagnosed with MBC (18-39 years) participating in a prospective interventional study (Young, Empowered, and Strong) at Dana-Farber Cancer Institute completed an electronic survey following enrollment. Measures evaluated sociodemographics, health behaviors, quality of life, and symptoms, among others. We used two-sided Fisher's exact tests to determine associations between concerns (e.g., cancer progression, side effects, lifestyle, finances, fertility) and demographic variables. RESULTS: Among 77 participants enrolled from 9/2020-12/2022, average age at MBC diagnosis and survey was 35.9 (range: 22-39) and 38.3 years (range: 27-46), respectively. Most were non-Hispanic white (83.8%) and 40.3% reported their diagnosis caused some financial problems. Many were concerned about fertility (27.0%), long-term treatment side effects (67.6%), exercise (61.6%), and diet (54.1%). Select concerns varied significantly by age, race/ethnicity, and education. Younger women at survey reported greater concern about familial cancer risk (p = 0.028). Women from minority racial/ethnic groups more frequently reported issues talking about their cancer to family/friends (p = 0.040) while those with more education were more frequently concerned with long-term effects of cancer on their health (p = 0.021). CONCLUSION: Young women living with MBC frequently report psychosocial, health, and cancer management concerns. Tailoring supportive care and communications to address prevalent concerns including disease progression and treatment side effects may optimize wellbeing.

Aspirin vs Placebo as Adjuvant Therapy for Breast Cancer: The Alliance A011502 Randomized Trial.

Importance: Observational studies of survivors of breast cancer and prospective trials of aspirin for cardiovascular disease suggest improved breast cancer survival among aspirin users, but prospective studies of aspirin to prevent breast cancer recurrence are lacking. Objective: To determine whether aspirin decreases the risk of invasive cancer events among survivors of breast cancer. Design, Setting, and Participants: A011502, a phase 3, randomized, placebo-controlled, double-blind trial conducted in the United States and Canada with 3020 participants who had high-risk nonmetastatic breast cancer, enrolled participants from 534 sites from January 6, 2017, through December 4, 2020, with follow-up to March 4, 2023. Interventions: Participants were randomized (stratified for hormone receptor status [positive vs negative], body mass index [≤30 vs >30], stage II vs III, and time since diagnosis [<18 vs ≥18 months]) to receive 300 mg of aspirin (n = 1510) or placebo once daily (n = 1510) for 5 years. Main Outcomes and Measures: The primary outcome was invasive disease-free survival. Overall survival was a key secondary outcome. Results: A total of 3020 participants were randomized when the data and safety monitoring committee recommended suspending the study at the first interim analysis because the hazard ratio had crossed the prespecified futility bound. By median follow-up of 33.8 months (range, 0.1-72.6 months), 253 invasive disease-free survival events were observed (141 in the aspirin group and 112 in the placebo group), yielding a hazard ratio of 1.27 (95% CI, 0.99-1.63; P = .06). All invasive disease-free survival events, including death, invasive progression (both distant and locoregional), and new primary events, were numerically higher in the aspirin group, although the differences were not statistically significant. There was no difference in overall survival (hazard ratio, 1.19; 95% CI, 0.82-1.72). Rates of grades 3 and 4 adverse events were similar in both groups. Conclusion and Relevance: Among participants with high-risk nonmetastatic breast cancer, daily aspirin therapy did not improve risk of breast cancer recurrence or survival in early follow-up. Despite its promise and wide availability, aspirin should not be recommended as an adjuvant breast cancer treatment. Trial Registration: ClinicalTrials.gov Identifier: NCT02927249.

Second Primary Breast Cancer in Young Breast Cancer Survivors.

Importance: Among women diagnosed with primary breast cancer (BC) at or younger than age 40 years, prior data suggest that their risk of a second primary BC (SPBC) is higher than that of women who are older when they develop a first primary BC. Objective: To estimate cumulative incidence and characterize risk factors of SPBC among young patients with BC. Design, Setting, and Participants: Participants were enrolled in the Young Women's Breast Cancer Study, a prospective study of 1297 women aged 40 years or younger who were diagnosed with stage 0 to III BC from August 2006 to June 2015. Demographic, genetic testing, treatment, and outcome data were collected by patient surveys and medical record review. A time-to-event analysis was used to account for competing risks when determining cumulative incidence of SPBC, and Fine-Gray subdistribution hazard models were used to evaluate associations between clinical factors and SPBC risk. Data were analyzed from January to May 2023. Main Outcomes and Measures: The 5- and 10- year cumulative incidence of SPBC. Results: In all, 685 women with stage 0 to III BC (mean [SD] age at primary BC diagnosis, 36 [4] years) who underwent unilateral mastectomy or lumpectomy as the primary surgery for BC were included in the analysis. Over a median (IQR) follow-up of 10.0 (7.4-12.1) years, 17 patients (2.5%) developed an SPBC; 2 of these patients had cancer in the ipsilateral breast after lumpectomy. The median (IQR) time from primary BC diagnosis to SPBC was 4.2 (3.3-5.6) years. Among 577 women who underwent genetic testing, the 10-year risk of SPBC was 2.2% for women who did not carry a pathogenic variant (12 of 544) and 8.9% for carriers of a pathogenic variant (3 of 33). In multivariate analyses, the risk of SPBC was higher among PV carriers vs noncarriers (subdistribution hazard ratio [sHR], 5.27; 95% CI, 1.43-19.43) and women with primary in situ BC vs invasive BC (sHR, 5.61; 95% CI, 1.52-20.70). Conclusions: Findings of this cohort study suggest that young BC survivors without a germline pathogenic variant have a low risk of developing a SPBC in the first 10 years after diagnosis. Findings from germline genetic testing may inform treatment decision-making and follow-up care considerations in this population.

Clinicopathological characteristics and eligibility for adjuvant olaparib of germline BRCA1/2 mutation carriers with HER2-negative early breast cancer.

Following the survival benefit demonstrated in the OlympiA trial, one year of adjuvant olaparib is now recommended for all patients with germline BRCA1/2 pathogenic/likely pathogenic variants (PV) and high-risk, HER2-negative early breast cancer after chemotherapy. However, optimal identification of high-risk patients who may derive benefit from this genomically-directed therapy is debated. In this study, we sought to characterize the real-world proportion of gBRCA1/2 PV carriers eligible for adjuvant olaparib according to the OlympiA criteria, and to compare clinicopathologic characteristics and outcomes between eligible and ineligible patients.

Exemestane plus everolimus and palbociclib in metastatic breast cancer: clinical response and genomic/transcriptomic determinants of resistance in a phase I/II trial.

The landscape of cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) resistance is still being elucidated and the optimal subsequent therapy to overcome resistance remains uncertain. Here we present the final results of a phase Ib/IIa, open-label trial (NCT02871791) of exemestane plus everolimus and palbociclib for CDK4/6i-resistant metastatic breast cancer. The primary objective of phase Ib was to evaluate safety and tolerability and determine the maximum tolerated dose/recommended phase II dose (100 mg palbociclib, 5 mg everolimus, 25 mg exemestane). The primary objective of phase IIa was to determine the clinical benefit rate (18.8%, n = 6/32), which did not meet the predefined endpoint (65%). Secondary objectives included pharmacokinetic profiling (phase Ib), objective response rate, disease control rate, duration of response, and progression free survival (phase IIa), and correlative multi-omics analysis to investigate biomarkers of resistance to CDK4/6i. All participants were female. Multi-omics data from the phase IIa patients (n = 24 tumor/17 blood biopsy exomes; n = 27 tumor transcriptomes) showed potential mechanisms of resistance (convergent evolution of HER2 activation, BRAFV600E), identified joint genomic/transcriptomic resistance features (ESR1 mutations, high estrogen receptor pathway activity, and a Luminal A/B subtype; ERBB2/BRAF mutations, high RTK/MAPK pathway activity, and a HER2-E subtype), and provided hypothesis-generating results suggesting that mTOR pathway activation correlates with response to the trial's therapy. Our results illustrate how genome and transcriptome sequencing may help better identify patients likely to respond to CDK4/6i therapies.