Partridge, Ann H.

Background The authors conducted a cluster randomized study to determine the effect of an exportable educational intervention for young women with breast cancer (YWI) on improving care. Methods Sites were randomized 1:1 to the YWI or a contact time control physical activity intervention (PAI) stratified by academic or community site. Up to 15 women aged ≤45 years with newly diagnosed breast cancer were enrolled at each of 14 academic sites and 10 were enrolled at each of 40 community sites. The primary endpoint, attention to fertility, was ascertained by medical record review. Statistical inferences concerning the effect of the intervention used general estimating equations for clustered data. Results A total of 467 patients across 54 sites were enrolled between July 2012 and December 2013. The median age of the patients at the time of diagnosis was 40 years (range, 22‐45 years). Attention to fertility by 3 months was observed in 55% of patients in the YWI and 58% of patients in the PAI ( P = .88). Rates were found to be strongly correlated with age ( P < .0001), and were highest in patients aged <30 years. Attention to genetics was similar (80% in the YWI and 81% in the PAI), whereas attention to emotional health was higher in patients in the YWI (87% vs 76%; estimated odds ratio, 2.63 [95% confidence interval, 1.20‐5.76; P = .016]). Patients rated both interventions as valuable in providing education (64% in the YWI and 63% in the PAI). Conclusions The current study failed to demonstrate differences in attention to fertility with an intervention to improve care for women with breast cancer, although attention to fertility was found to be higher than expected in both groups and emotional health was improved in the YWI group. Greater attention to young women with breast cancer in general may promote more comprehensive care for this population.

10065 Background: Prospective data regarding fertility and pregnancy after breast cancer are limited. Many young survivors are interested future fertility, but pregnancy rates among women attempting and not attempting pregnancy have not been studied prospectively. Methods: As part of a multicenter cohort study, women diagnosed age ≤40 with stage 0-3 breast cancer are surveyed at baseline then annually regarding fertility interest, attempts, and pregnancies. Chi-square tests were used to compare proportions attempting and achieving pregnancy. Results: At least once in the 5 years (yrs) after Dx, 334/959 (35%) women reported interest in future biologic children. The percent interested was stable in the first 3 yrs then declined: 256 (27%, baseline), 244 (27%, 1 year), 209 (25%, 2 yrs), 176 (25%, 3 yrs), 106 (18%, 4 yrs), and 72 (16%, 5 yrs). Pregnancy was attempted by 104/334 (31%) of women who reported interest and 4/625 (1%) who did not. Pregnancy occurred in 118 women (12%), including 76/108 (70%) who attempted and 42/851 (5%) who did not. Attempts and achieving pregnancy were associated with younger age, partnered status, and not having children prior to Dx (table). Lower stage was associated with attempting pregnancy and ER negative disease with achieving pregnancy. Conclusions: A substantial number of young women become pregnant in the 5 years after a breast cancer diagnosis. Given that over 1/3 of pregnancies were among women who did not report attempting, additional attention to contraception counseling should be considered. Further evaluation of assisted reproductive technology use, pregnancy and disease outcomes in this cohort, and the POSITIVE Trial (NCT02308085) will shed light on the feasibility and safety of pregnancy after breast cancer. [Table: see text]

6520 Background: Breast cancer follow-up guidelines recommend imaging for distant metastases only in the presence of signs/symptoms. However, data supporting this recommendation predates the current era of improved imaging and targeted therapies based on molecular subtype. The objective was to assess the relationship between mode of distant recurrence detection and survival. Methods: A stage-stratified random sample of Stage II-III breast cancer patients diagnosed in 2006-7 was selected from NCDB records from 1,217 CoC-accredited facilities (10/hospital n = 10,853). Women were categorized by subtype: 1) ER or PR+/HER2-; 2) ER and PR-/Her2- (triple negative); 3) HER2+. Medical records abstracted for 5-years post-surgery supplemented NCDB data and assessed distant recurrence and mode of detection (prompted by signs/symptoms or surveillance imaging), imaging (chest CT, abdomen/pelvis CT/MRI, head CT/MRI, bone scan, PET/CT), death date. The relationship between mode of recurrence detection and days from initial cancer diagnosis to death was assessed using propensity-weighted multivariable Cox proportional hazards regression stratified by subtype. Propensity weights, based on receipt of surveillance systemic imaging, accounted for sociodemographic and tumor/treatment factors. Results: 5-year distant recurrence was 22.3% for triple negative, 14.8% HER2+, and 11.2% for ER or PR+/ HER2- patients. Asymptomatic imaging detected recurrence in 22.9% and signs/symptoms in 77.1%. Patients with asymptomatic as compared to sign/symptom detected recurrences had reduced risk of death in 5 years if triple negative (HR = 0.68, 95% CI = 0.50-0.93) or HER2+ (HR = 0.40, 95% CI = 0.24-0.65) with no significant association for ER or PR+/HER2- (HR = 1.2, 95% CI = 0.88-1.51). This translated to a between-group difference in weighted median survival of 5 months for triple negative and 13 months for HER2+ patients. Conclusions: This is the first nationally representative study to show a survival advantage with asymptomatic detection of distant metastases for patients, with the benefit limited to triple negative and HER2+ disease. Further research to confirm observational findings is warranted.

531 Background: The greatest age disparity in early stage breast cancer (BC) outcomes is in young women with hormone receptor positive (HR+) BC. While differences in biology may play a role, understanding the role of non-persistence (early discontinuation) with endocrine therapy (ET) is critical given the demonstrated efficacy of ET in this population. Methods: As part of a prospective cohort that enrolled women with BC diagnosed (dx) at age ≤40 between 2006-2016, we identified women with HR+, Stage I-III BC. Socio-demographic and treatment information, fertility concerns and confidence with the ET treatment decision were assessed by survey within 1 yr of dx. Medical record review was used to ascertain stage and HR status. Women who initiated ET but did not report taking tamoxifen or an aromatase inhibitor at 3 yrs post-diagnosis (or last follow-up if <3 yrs) were classified as non-persistent. Chi-square tests were used to compare categorical variables between persisters and non-persisters and stepwise multivariable regression to evaluate predictors of non-persistence. Results: In 538 women who initiated ET, median age at dx was 36; 10% were non-persistent. Discontinuation of ET was more likely in those who were less confident with their ET decision compared to those who were more confident (25/179, 14% vs 18/263, 7%, p=0.01). A greater proportion of women concerned about fertility discontinued vs. women not concerned (29/213,14% vs 25/319, 8%, p=0.03), and fertility concerns were associated with non-persistence in multi-variable analyses (OR: 1.85, 95% CI 1.05-3.26, p=0.03). Age at dx, race, education, employment, financial comfort, marital status, parity, stage, chemotherapy and local therapy were not associated with non-persistence. Conclusions: A significant minority of women with HR+ BC discontinued ET within 3 yrs. The association between fertility concerns expressed soon after dx and non-persistence underscores a need to address psychosocial issues that can impact treatment decisions in young women. Strategies to reduce decisional conflict and increasing confidence with the choice to take ET, may influence persistence. Future work will evaluate the contribution of other factors (eg symptom burden) to non-persistence.

526 Background: Young age at diagnosis (dx) is a predictor of worse prognosis in patients (pts) with luminal breast cancer (BC). Poorer adherence to endocrine therapy (ET) among younger women may contribute to this disparity. Aim: To assess non-adherent behaviors and associated factors among young women with stage 1-3 hormone receptor (HR)+ BC taking ET. Methods: This study is a part of a multi-center, prospective cohort of pts with dx of BC at or under age 40. On a survey 30 months after dx, among pts reporting taking ET, adherence was measured using a 3-item Likert-type scale (Do you ever forget to take your ET? If you feel worse when you take your ET, do you stop taking it? Did you take your ET exactly as directed by your doctor?). Pts reporting any non-adherent behavior during the last 3 months were classified as non-adherers. Variables with a p-value <0.20 were included in a multivariate logistic model. Results: Among361 pts eligible for this analysis, 174 (48%) reported some non-adherent behaviors in the last 3 months; 56 (16%) moderate or greater non-adherent behaviors. None of the studied variables was associated with non-adherent behaviors (table). Conclusions: Non-adherent behaviors to ET are present in almost half of the young women with HR+ BC. Further analyses of explanatory factors and impact of non-adherence are required to understand and potentially improve this problem. [Table: see text]