Sorouri, Kimia

632 Background: Prospective data on the risk of breast cancer (BC) recurrence among young BC survivors who have a subsequent pregnancy are limited. We sought to evaluate the long-term impact of pregnancy and live birth on BC outcomes in the Young Women’s Breast Cancer Study (NCT01468246), a prospective multicenter study of women aged ≤40 years at BC diagnosis. Methods: Women with stage 0-III BC without prior hysterectomy were included. The primary endpoint was breast cancer-free interval (BCFI) between patients with and without a (a) pregnancy and (b) live birth after BC. Secondary endpoints were distant recurrence-free interval (DRFI) and overall survival (OS). A time-varying Cox proportional hazards model was performed by estrogen receptor (ER) status, controlling for age at diagnosis, tumor stage, HER2 status, tumor grade, parity at diagnosis, and germline pathogenic variant status. Results: Among 1,016 BC survivors at a median follow-up of 12 (range, 0.5-18.5) years, 198 reported ≥1 pregnancy and 165 reported ≥1 live birth post-diagnosis. Among survivors who reported a post-diagnosis pregnancy, median age at diagnosis was 32 (range, 17-40) years; most had stage I (35%) or II (40%) BC, with 72% hormone receptor (HR)-positive and 25% HER2+; 42% were nulligravid and 60% were nulliparous at diagnosis. Among BC survivors who did not become pregnant post-diagnosis, median age at diagnosis was 37 (range, 21-40) years; most had stage I (35%) or II (43%) BC, with 75% HR-positive and 28% HER2+; 25% were nulligravid and 29% were nulliparous at diagnosis. Among BC survivors with ER-positive tumors (n = 737), pregnancy after BC was not associated with a difference in BCFI (adjusted hazard ratio [HR] 0.60, 95% CI 0.31-1.16, P = 0.130), DRFI (HR 0.73, 95% CI 0.35-1.55, P = 0.416), or OS (HR 0.58, 95% CI 0.24-1.40, P = 0.227). Similarly, live birth after BC did not impact BCFI (HR 0.83, 95% CI 0.45-1.55, P = 0.560), DRFI (HR 1.04, 95% CI 0.52-2.06, P = 0.923), or OS (HR 0.77, 95% CI 0.34-1.76, P = 0.541). Outcomes among BC survivors with ER-negative tumors (n = 278) were also not affected by post-diagnosis pregnancy (BCFI [HR 1.48, 95% CI 0.70-3.14, P = 0.304], DRFI [HR 1.59, 95% CI 0.68-3.75, P = 0.287], OS [HR 0.99, 95% CI 0.39-2.49, P = 0.975]) or live birth (BCFI [HR 1.02, 95% CI 0.41-2.53, P = 0.974], DRFI [HR 0.80, 95% CI 0.24-2.69, P = 0.722], OS [HR 0.39, 95% CI 0.09-1.69, P = 0.208]). Conclusions: In this multicenter, prospective study with 12 years of median follow-up, pregnancy and live birth after BC did not impact BC events or overall survival, irrespective of ER status. These long-term data from a modern cohort provide reassurance for young BC patients interested in future fertility. Clinical trial information: NCT01468246 .

The rising incidence of cancer among young women highlights the importance of understanding treatment‐related gonadotoxicity, which can lead to infertility and long‐term health complications from premature estrogen decline. Although anti‐Müllerian hormone is considered the most reliable indicator of ovarian reserve, its interpretation among oncology patients is complex because it is dependent on the treatment modality, necessitating further research to fully understand the impact of specific treatments on anti‐Müllerian hormone and to identify alternative markers to reliably assess the ovarian toxicity of newer cancer therapies.

ABSTRACTBackgroundFollowing breast cancer (BC), many young women are interested in future childbearing and some may wish to breastfeed. However, limited information is available regarding their lactation experiences.MethodsParticipants in the Young Women's Breast Cancer Study, a multicenter, prospective cohort study of women ≤40 years diagnosed with stage 0–III BC between 2006–2016 and who reported one or more live births following diagnosis, were surveyed about pregnancy and breastfeeding after BC treatment, including reasons for attempting and stopping breastfeeding, satisfaction, and supports.ResultsOf 143 eligible women sent a survey, 115 responded and 94 were included in the analytic cohort. Breastfeeding was attempted by 55% of women (52 of 94). Among those who had not attempted, 93% noted prior bilateral mastectomies (39 of 42). Among those who attempted breastfeeding, 69% had undergone lumpectomy and radiotherapy (36 of 52), 83% of whom reported no milk production from their treated breast (30 of 36). Most (65%, 34 of 52) were at least somewhat satisfied with their ability to breastfeed. Reasons for stopping breastfeeding included: having completed the planned duration (36%, 19 of 52); to start/resume endocrine therapy (21%, 11 of 52); and to resume breast imaging (8%, 4 of 52). Approximately half (27 of 55) of women who had not undergone bilateral mastectomies recalled receiving specific information about breastfeeding after BC, mostly from the oncology team (59%, 16 of 27), online resources (48%, 13 of 27), or a lactation consultant (44%, 12 of 27).ConclusionMost young BC survivors who attempted to breastfeed were able to and were satisfied with the experience, despite challenges. Specific resources to support BC survivors who wish to breastfeed are needed.

1518 Background: Despite high interest among young women diagnosed with breast cancer (BC) in future fertility, prior research has been hampered by short follow-up and lack of prospective assessment of pregnancy attempts. We sought to describe fertility outcomes among young women participating in a prospective cohort who reported pregnancy attempt post-BC diagnosis. Methods: Women with stage 0-III BC in the Young Women's Breast Cancer Study (YWS, NCT01468246), a multicenter, prospective cohort of women diagnosed at age ≤40 from 2006-2016 who reported attempting pregnancy post-diagnosis were included. Those with prior hysterectomy, bilateral oophorectomy, or metastatic disease at diagnosis were excluded. Data on attempting pregnancy and fertility outcomes were obtained from serial surveys. Multivariable logistic regression with stepwise model selection was used to identify factors associated with pregnancy and live birth. Results: Among 1213 eligible participants, 197 reported any attempt of pregnancy (16%) over a median follow-up of 11 years (range: 3-17). Among attempters, median age at diagnosis was 32 years (range: 17-40); 74% were non-Hispanic White; 41% had stage I, 35% stage II, 10% stage III, and 14% stage 0 BC; 76% had HR+ disease; 68% received chemotherapy; 57% received endocrine therapy within one year post-diagnosis; 13% were BRCA1/2 pathogenic variant (PV) carriers; 51% reported financial comfort at baseline; 51% were nulligravida and 72% nulliparous at diagnosis; 28% had undergone fertility preservation consisting of egg/embryo freezing at diagnosis; 15% reported a history of infertility before BC diagnosis. Most (73%) reported ≥1 pregnancy after diagnosis and 65% reported ≥1 live birth. Median time from diagnosis to first pregnancy was 48 months (range: 6-125). In the multivariable model, greater age at diagnosis (odds ratio [OR] 0.82 per year increase, 95% CI 0.74-0.90, P<0.0001) was negatively associated with pregnancy, while financial comfort at baseline (OR 2.04, 95% CI 1.01-4.12, P=0.047) was predictive of pregnancy. For live births, greater age at diagnosis was negatively associated (OR 0.82 per year increase, CI 95% 0.76-0.90, P<0.0001) while having undergone fertility preservation at diagnosis was predictive (OR 2.78, 95% CI 1.29-6.00, P=0.009). History of infertility, nulliparity at diagnosis, tumor characteristics, cancer treatment, race, ethnicity, and BRCA1/2 PV status were not associated with either outcome. Conclusions: This is the first prospective study with greater than 10 years of follow-up to report fertility outcomes in young BC survivors accounting for attempting pregnancy. The majority achieved a pregnancy and most reported a live birth. Our findings can be incorporated into the counseling of young BC patients and survivors, and highlight the need for accessibility of fertility preservation services for this population. Clinical trial information: NCT01468246 .

AbstractBackgroundBreast cancer (BC) is the most common malignancy in women of reproductive age. This study sought to explore the postcancer conception and pregnancy experience of young BC survivors to inform counseling.MethodsIn the Young Women's Breast Cancer Study (NCT01468246), a multicenter, prospective cohort, participants diagnosed at age ≤40 years with stage 0‐III BC who reported ≥1 postdiagnosis live birth were sent an investigator‐developed survey.ResultsOf 119 eligible women, 94 (79%) completed the survey. Median age at diagnosis was 32 years (range, 17–40) and at first postdiagnosis delivery was 38 years (range, 29–47). Most had stage I or II (77%) and HR+ (78%) BC; 51% were nulligravida at diagnosis. After BC treatment, most (62%) conceived naturally, though 38% used assisted reproductive technology, 74% of whom first attempted natural conception for a median of 9 months (range, 2–48). Among women with a known inherited pathogenic variant (n = 20), two underwent preimplantation genetic testing. Of 59 women on endocrine therapy before pregnancy, 26% did not resume treatment. Hypertensive disorders of pregnancy (20%) was the most common obstetrical condition. Nine percent of newborns required neonatal intensive care unit admission and 9% had low birth weight.ConclusionAmong women with live births after BC treatment, most conceived naturally and having a history of BC did not appear to negatively impact pregnancy complications, though the high rate of hypertensive disorders of pregnancy warrants further investigation. The prolonged period of attempting natural conception for some survivors suggests the potential need for improved understanding and counseling surrounding family planning goals after BC.

Abstract Background: Breast cancer (BC) is the most common malignancy among women of reproductive age. Given limited data describing the conception and pregnancy experience of young BC survivors, we sought to explore these outcomes to inform counseling of women interested in future childbearing. Methods: Participants with stage 0-III BC in the Young Women’s Breast Cancer Study (NCT01468246), a multi-center, prospective cohort of women diagnosed at age ≤ 40 from 2006-2016 who reported ≥ 1 live birth from a pregnancy after diagnosis were sent a survey with investigator-developed questions focused on their first post-diagnosis live birth. Women who had been diagnosed with BC during pregnancy were excluded from this analysis. The survey assessed conception, use of assisted reproductive technology (ART), pre-implantation genetic testing (PGT), endocrine therapy (ET), and peripartum complications. Summary statistics are presented. Results: 92/119 eligible women completed the survey (response rate: 77%). Median age at diagnosis was 32 (range:17-40) years and at delivery was 37 (range: 29-47) years. Median time from diagnosis to delivery was 58 months (range: 11-154). Most women had stage 2 BC (43%, 40/92); 68% received chemotherapy (63/92); about half (51%, 47/92) were nulligravida at diagnosis. Overall, 61% of pregnancies were conceived naturally (56/92) and 39% with ART (36/92): 32% by in-vitro fertilization (IVF, 29/92), 7% with fertility medications only (6/92), and 1 with intrauterine insemination. 38% of IVF pregnancies were conceived using products from fertility preservation prior to BC treatment (11/29). Among women who used ART, 74% attempted to conceive naturally (25/36) for a median of 9 (range: 2-48) months prior to pursuing ART. The most common reasons for pursuing ART include infertility following BC treatment (33%, 12/36) and expediting conception to resume treatment (17%, 6/36). 11% of those with known inherited pathologic variant mutations underwent PGT (2/19). Reasons for not pursuing PGT included belief in more effective cancer risk reduction in the future (29%, 5/17), not being offered PGT (24%, 4/17), high cost (12%, 2/17), no interest in IVF (12%, 2/17), acceptable odds for inheriting the mutation (24%, 4/17), and belief in other risk reduction strategies (18%, 3/17); 1 woman reported ethical concerns. Of 57 women who took ET pre-pregnancy (63%), nearly all (96%, 55/57) discontinued ET &gt; 3 months prior to attempting to conceive; 1 discontinued after awareness of pregnancy. Of those who had received prior ET, 60% resumed ET (34/57) a median of 3 (range: 1-50) months after pregnancy. Among 23 women who did not resume, 13 (23%) had completed the recommended duration; the remaining 10 reported one or more of the following reasons: felt better while off (28%, 6/23), desire for another child (22%, 5/23), and desire to breastfeed (17%, 4/23). Median time to delivery was 39 (range: 28-42) weeks with 12% delivering preterm &lt; 37 weeks (11/92). 47% had a Caesarean section (43/92), with prolonged labor the most common indication (33%, 14/43). Hypertensive disorders of pregnancy (HDP, 20%, 18/92), gestational diabetes (7%, 6/92), small for gestational age (7%, 6/92), and postpartum hemorrhage (5%, 5/92) were the most common obstetrical complications. 9% of women had newborns requiring NICU admission (8/92) and 9% had low birth weight (8/92). Conclusion: Among young BC survivors with a live birth following diagnosis, most conceived naturally, with the majority who used ART first attempting natural conception. There was limited use of PGT among mutation carriers with ¼ not having been offered testing. Patient reported peripartum complications appear consistent with population norms, though the relatively higher rate of HDP bears further research. Among those yet to complete their ET, a notable proportion did not resume following delivery. This novel data may help to inform the care of young breast cancer survivors pursuing pregnancy. Citation Format: Kimia Sorouri, Tal Sella, Shoshana Rosenberg, Margaret Loucks, Kathryn Ruddy, Shari I. Gelber, Rulla M. Tamimi, Jeffrey M. Peppercorn, Lidia Schapira, Virginia F. Borges, Steven E. Come, Ellen Warner, Ann Partridge. Conception and Pregnancy Among Young Breast Cancer Survivors [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-08-05.

Abstract Background: Breast cancer (BC) is the most common malignancy in women of reproductive age, and the incidence of the disease is rising in this population. Many of these women are interested in childbearing after their BC treatment and a substantial minority will go on to have a live birth. Some will also want to breastfeed. However, there is only limited information available regarding the experience of young BC survivors breastfeeding following treatment. Methods: Participants in the Young Women’s Breast Cancer Study (YWS), a multi-center, prospective cohort study of women diagnosed with BC at age ≤ 40 years between 2006-2016, who reported at least one live birth following their diagnosis with stage 0-III BC were sent an additional survey including investigator-developed questions focused on breastfeeding after breast cancer treatment. Women who had been diagnosed with BC during pregnancy were excluded from this analysis. The survey assessed whether they breastfed, reasons for attempting and stopping breastfeeding, breastfeeding with the treated breast and untreated breast, and supports. Summary statistics, including medians and proportions, are presented. Results: Of 118 eligible women sent a survey, 92 completed the survey (78% response rate). Median age at diagnosis of BC was 32 (range: 17-40) years and at delivery was 37 (range: 29-47) years. 54% of women had attempted to breastfeed (50/92). Among those who had not, 93% noted a history of bilateral mastectomies (39/42). Additional reasons for not attempting to breastfeed included no interest regardless of BC history (5%, 2/42) and 1 woman underwent a unilateral mastectomy and did not think her supply would be sufficient. Among the women who did attempt breastfeeding, 68% had undergone lumpectomy and radiotherapy (34/50) with 85% of those women reporting that the treated breast did not produce milk (29/34). The 5 women who produced milk from the treated breast noted that the supply was substantially less than the untreated breast. To assist with breastfeeding, 76% used a pump only on the untreated breast (38/50) and 14% on both breasts (7/50). Women breastfed for a median of 5.5 (range:&lt; 1-60) months and 64% were “somewhat”/“very much” satisfied with their ability to breastfeed (32/50). The most common reasons cited for stopping breastfeeding included having completed the planned duration (36%, 18/50), to start/resume endocrine therapy (22%, 11/50), and to resume breast imaging (8%, 4/50). Among patients who had not undergone a double mastectomy, 47% recalled receiving specific information about breastfeeding after a history of breast cancer (25/53), most commonly from the oncology team (56%, 14/25), lactation consultant (48%, 12/25), or online resources (44%, 11/25). Conclusion: In the largest series to date detailing the breastfeeding experiences of young BC survivors, approximately half of young BC survivors with a successful pregnancy attempted to breastfeed. Among those who had undergone prior lumpectomy and radiotherapy, women reported no milk production or only limited supply from the treated breast. Despite these limitations, most women who attempted to breastfeed were satisfied with their ability to do so. Specific resources to support the experience of breastfeeding in BC survivors are needed. Citation Format: Tal Sella, Kimia Sorouri, Shoshana Rosenberg, Margaret Loucks, Kathryn Ruddy, Shari I. Gelber, Rulla M. Tamimi, Jeffrey M. Peppercorn, Lidia Schapira, Virginia F. Borges, Steven E. Come, Ellen Warner, Ann Partridge. Breastfeeding in Survivors of Early Breast Cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-08-06.