Partridge, Ann H.

Recent epidemiologic data show an increasing incidence of breast cancer among premenopausal women in many higher-income countries. Among premenopausal women, those diagnosed under age 40 years experience inferior long-term outcomes, particularly in the setting of hormone receptor–positive, human epidermal growth factor receptor 2–negative disease. In addition to more advanced disease presentation and/or less favorable disease biology, suboptimal adjuvant endocrine therapy (ET) has emerged as an important driver of this age-related disparity. Historically, young women have been excluded from treatment with aromatase inhibitors (AIs), attained low rates of chemotherapy-related amenorrhea, and exhibited low adherence to ET. Recently, several studies have demonstrated treatment with ovarian function suppression (OFS) during the first 5 years postdiagnosis to be associated with improvements in breast cancer recurrence and mortality, with additional benefits achieved from pairing OFS with an AI. As the first 5 years of ET for premenopausal women has been transformed, extended ET, administered in years 5-10 postdiagnosis, has also become more common. However, the only studies of extending ET in premenopausal women have tested an additional 5 years of tamoxifen following an initial 5 years of tamoxifen and studies of AIs in the second 5 years have been limited to postmenopausal women. Herein, we review available data concerning potential benefits and risks to be considered when counseling premenopausal women on extended ET, including the continuation of OFS. We offer a pragmatic framework to support decision making given the current body of knowledge and call out the need for additional research into this issue.

Background Fear of cancer recurrence (FCR) is more intense in younger women. Because FCR is a powerful determinant of quality of life, identifying those at risk for persistently elevated FCR can inform timing of interventions. Methods A total of 965 women with stage 0 to stage III breast cancer enrolled in the Young Women's Breast Cancer Study, a prospective cohort of women diagnosed with breast cancer at age ≤40 years, completed the 3‐item Lasry Fear of Recurrence Index. Group‐based trajectory modeling was used to classify distinct FCR patterns from baseline through 5 years post‐diagnosis. Multinomial logistic regression was used to identify patient, disease, and treatment characteristics associated with each trajectory. Results Five FCR trajectories were identified with the majority of participants having moderate (33.1%) or high FCR (27.6%) that improved over time. A total of 6.9% participants had moderate FCR that worsened, whereas 21.7% had high FCR at baseline that remained high throughout. In the fully adjusted multinomial model, stages II and III (vs stage I) were associated with higher odds of being in the high/stable trajectory, whereas stage 0 (vs I), being financially comfortable (vs not comfortable), was associated with lower odds of being in the high/stable trajectory. White (vs non‐White) was associated with higher odds of being in a trajectory that improved over time. Conclusions Although FCR improves over time for many young women with breast cancer, approximately one‐third had FCR that was severe and did not improve or worsened over 5 years after diagnosis. Ongoing monitoring is warranted, with early referral to mental health professionals indicated for those at highest risk for unresolved FCR. Lay Summary Fear of recurrence is common among young women with breast cancer. The authors followed a large cohort of young women diagnosed with breast cancer when they were 40 years of age and younger, and found 5 distinct trajectories that show moderate and severe fears do not always improve over time and may require targeted mental health intervention.

PURPOSE Many patients and physicians remain concerned about the potential detrimental effects of pregnancy after breast cancer (BC) in terms of reproductive outcomes and maternal safety. This systematic review and meta-analysis aimed at providing updated evidence on these topics. METHODS A systematic literature review was conducted to identify studies including patients with a pregnancy after BC (PROSPERO number CRD42020158324). Likelihood of pregnancy after BC, their reproductive outcomes, and maternal safety were assessed. Pooled relative risks, odds ratios (ORs), and hazard ratios (HRs) with 95% CIs were calculated using random effects models. RESULTS Of 6,462 identified records, 39 were included involving 8,093,401 women from the general population and 112,840 patients with BC of whom 7,505 had a pregnancy after diagnosis. BC survivors were significantly less likely to have a subsequent pregnancy compared with the general population (relative risk, 0.40; 95% CI, 0.32 to 0.49). Risks of caesarean section (OR, 1.14; 95% CI, 1.04 to 1.25), low birth weight (OR, 1.50; 95% CI, 1.31 to 1.73), preterm birth (OR, 1.45; 95% CI, 1.11 to 1.88), and small for gestational age (OR, 1.16; 95% CI, 1.01 to 1.33) were significantly higher in BC survivors, particularly in those with previous chemotherapy exposure, compared with the general population. No significantly increased risk of congenital abnormalities or other reproductive complications were observed. Compared to patients with BC without subsequent pregnancy, those with a pregnancy had better disease-free survival (HR, 0.66; 95% CI, 0.49 to 0.89) and overall survival (HR, 0.56; 95% CI, 0.45 to 0.68). Similar results were observed after correcting for potential confounders and irrespective of patient, tumor, and treatment characteristics, pregnancy outcome, and timing of pregnancy. CONCLUSION These results provide reassuring evidence on the safety of conceiving in BC survivors. Patients' pregnancy desire should be considered a crucial component of their survivorship care plan.

PURPOSE The ATEMPT trial was designed to determine if treatment with trastuzumab emtansine (T-DM1) caused less toxicity than paclitaxel plus trastuzumab (TH) and yielded clinically acceptable invasive disease-free survival (iDFS) among patients with stage I human epidermal growth factor receptor 2–positive (HER2+) breast cancer (BC). METHODS Patients with stage I centrally confirmed HER2+ BC were randomly assigned 3:1 to T-DM1 or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or T 80 mg/m 2 IV with H once every week × 12 weeks (4 mg/kg load →2 mg/kg), followed by H × 39 weeks (6 mg/kg once every 3 weeks). The co-primary objectives were to compare the incidence of clinically relevant toxicities (CRTs) in patients treated with T-DM1 versus TH and to evaluate iDFS in patients receiving T-DM1. RESULTS The analysis population includes all 497 patients who initiated protocol therapy (383 T-DM1 and 114 TH). CRTs were experienced by 46% of patients on T-DM1 and 47% of patients on TH ( P = .83). The 3-year iDFS for T-DM1 was 97.8% (95% CI, 96.3 to 99.3), which rejected the null hypothesis ( P < .0001). Serially collected patient-reported outcomes indicated that patients treated with T-DM1 had less neuropathy and alopecia and better work productivity compared with patients on TH. CONCLUSION Among patients with stage I HER2+ BC, one year of adjuvant T-DM1 was associated with excellent 3-year iDFS, but was not associated with fewer CRT compared with TH.

12081 Background: Young women with breast cancer may be at increased risk for premature development of cardiovascular disease (CVD) in part due to their cancer treatment. Limited data are available on CVD risk among young breast cancer survivors. Methods: Women aged 30-40 years at diagnosis with stage 0-III breast cancer enrolled in a prospective cohort study of women diagnosed with breast cancer at ≤40 were eligible for inclusion in this analysis. Data were obtained from serial surveys and electronic medical records at breast cancer diagnosis and 5-year follow-up. We calculated “excess heart age,” which incorporates a CVD risk-based score (calculated using age, systolic blood pressure, blood pressure medication, diabetes, smoking, body mass index) to estimate the difference in years between an individual’s chronological age and their CVD-risk adjusted age. Multivariable logistic regression models (adjusting for age at diagnosis, stage, and race) were fitted to evaluate associations between treatment (radiation, endocrine therapy, anthracyclines, and trastuzumab) and having a change in excess heart age ≥2 years from baseline to 5 years. Results: Among 372 young breast cancer survivors, mean age at diagnosis was 36.6 (SD 2.89), 93% were white, and 79% were diagnosed with stage I or II breast cancer. Mean excess heart age was.32 (SD: 6.16) years at baseline, which declined to -.07 (SD 6.64) at 5-year follow-up (p=.17). At 5 years, 31% (n=114) of women experienced an increase of at least 2 years in their excess heart age since diagnosis, and their mean excess heart age was 4.34 years (range -9 to 30). In multivariable analyses, receipt of trastuzumab was associated with higher odds (OR: 1.68, 95% CI: 1.02-2.77) of experiencing an increase of ≥2 years in excess heart age between diagnosis and 5 years of follow-up. Endocrine therapy, anthracyclines, and radiation were not significantly associated with a change in excess heart age of ≥2 years at 5 years post-diagnosis. Conclusions: At 5 years post-diagnosis, approximately 1/3 of young breast cancer survivors experienced a change from baseline in their excess heart age of ≥2 years. Further research is warranted to confirm findings regarding trastuzumab and excess heart age, and potential effects on longer-term cardiac outcomes in this population. Extended follow-up of this cohort may further quantify CVD risk over time.[Table: see text]

e24108 Background: Clonal hematopoiesis of Indeterminate Potential (CHIP) is associated with adverse clinical outcomes including increased risk of hematologic malignancies and heart disease. Limited data suggest an increased prevalence of CHIP in patients treated for solid tumors, particularly after exposure to radiation and chemotherapy. CHIP testing may inform risk-reduction strategies for cancer survivors. Little is known about patient knowledge, attitudes, and preferences regarding CHIP testing. Methods: We surveyed survivors without history of recurrence participating in an ongoing prospective cohort study of young women with breast cancer (BC). The survey was sent by email and included an introduction to CHIP including risk factors and clinical associations. Respondents then reviewed a vignette and were asked about CHIP testing preferences (definitely/probably test vs. definitely/probably not test) considering sequentially: 1) population-based 10-year risk of BC recurrence, hematological malignancy and heart disease; 2) estimated increase in these risks with CHIP; 3) current CHIP management; 4) a dedicated CHIP clinic; and 5) a theoretical CHIP treatment. Changes in preferences from the prior scenario were evaluated with the McNemar's test using a type I error rate of 5%. Results: 528/642 (82.2%) eligible women responded to the survey, at a median age of 46 (range: 31-54) years (median time from diagnosis: 108 months (range: 60-168)), and 88% were white. Most had stage 1/2 BC (78.8%) and had received chemotherapy (73.1%) and/or radiation (61.9%). 93.6% had never heard of CHIP prior to survey. After initial patient vignette presentation, most women (87.1%,) recommended CHIP testing if offered. Preferences for testing decreased (p<0.05) when considering population-based risks, with 11.1% shifting their preference from CHIP testing to not testing. After considering increased risks associated with CHIP, interest in testing increased (p<0.05), with 10.1% shifting their preference to testing. Interest significantly (p<0.05) increased with the possibility of managing CHIP through a clinic or a hypothetical CHIP treatment, with 7.2% and 14.1% switching their preferences towards testing, respectively. Finally, 75.8% responded that they themselves, after learning about CHIP and reviewing the vignette, would want to have CHIP testing; 28.2% reported that learning about CHIP and the associated risks caused them at least moderate anxiety. Conclusion: Few young BC survivors were aware of CHIP yet most indicated an interest in testing after learning about it. Testing preferences were influenced by risks presented and potential management strategies. Findings highlight the importance of effective risk communication and the need for adequate psychosocial support when considering testing for CHIP and other potential clinical biomarkers predictive of cancer and other medical risks in cancer survivors.

e18561 Background: Young women with breast cancer (BC) have unique issues, including fertility, genetic, and emotional health concerns; these may sometimes be inadequately addressed by providers. Given documented disparities in BC care and outcomes, we sought to explore whether provider attention to these issues differs by race, as well as to examine racial differences in satisfaction with care among young patients with BC. Methods: The Young & Strong Study was a cluster randomized trial of an educational and supportive care intervention at 14 academic + 40 community oncology practices across the US enrolling women with newly diagnosed BC at age ≤45 and their providers. Patients completed surveys at baseline, 3, 6, and 12 months after enrollment. Race was self-reported at baseline. Provider attention to fertility, genetics, and emotional health was evaluated by medical record review. The proportions of patients with attention to these concerns by 3 months was compared by race (white, Black, Asian, multi-racial/other/unknown) using Fisher’s exact tests. Satisfaction with care was assessed with the Patient Satisfaction Questionnaire-18 (PSQ-18) at 3 months. Median scores for each of 7 PSQ-18 subscales (1-5 scale, higher scores=more satisfaction) were compared by race with the Kruskal-Wallis test. Results: 465/467 (99.6%) of enrolled patients had evaluable data. 77% were white, 12% Black, 4% Asian, and 7% multiracial/other/unk. Median age at diagnosis was 40 (range: 22-45) years. Provider attention to genetics (≥85%) and emotional health (≥90%) was high across groups, and there were no differences by race in attention to fertility, genetics, or emotional health (Table). Among 359/465 women (77%) who completed the PSQ-18, median subscale scores ranged from 3.5-4.5, indicating high levels of satisfaction with care. For the PSQ-18 technical quality domain, median scores were lower (p=.03), indicating less satisfaction, in Black and Asian women (4.0) and higher in white women (4.5). Median scores for other PSQ-18 domains (general satisfaction, interpersonal manner, communication, financial, time spent with doctor, accessibility) did not differ by race. Conclusions: Satisfaction with care was high and issues related to fertility, genetics and emotional health were addressed by providers in the majority of young women in our study, with minimal differences by race. These patients were all enrolled in a clinical trial and had access to high-quality care, limiting the generalizability of our findings. Larger, population-based studies in more diverse settings are warranted. Clinical trial information: NCT01647607. Attention to psychosocial concerns by race. [Table: see text]