Highlight 7

The last daily highlight on SABCS 2023 is done by Dr Christophe Van Berckelaer, a gynaecological oncologist at the University Hospital Antwerp.  He selected another four presentations from the general session 2.

The PREFERABLE-EFFECT study, presented by Anna May from the Netherlands, aimed to investigate the impact of supervised and individualized exercise in patients with metastatic breast cancer, focusing on fatigue and quality of life. The study included 350 patients recruited from eight clinical centers across Europe and Australia, randomized into two groups. The first group received exercise advice and a sports watch but did not undergo a structured intervention, while the second group participated in a nine-month individualized exercise program comprising aerobic, resistance, and balance training. Measurements were taken at baseline and at three, six, and nine months of follow-up. Primary endpoints included cancer-related physical fatigue and health-related quality of life, with physical fitness as a secondary endpoint. The results showed that patients in the training program experienced improved QoL and reduced fatigue, along with better physical and social functioning. Additionally, patients in the exercise group reported less pain and dyspnoea, countering concerns about increased pain associated with exercise. The findings suggest that supervised exercise should be considered as part of supportive care in patients in a palliative setting. It’s noteworthy that the exercise program did not have an impact on the emotional functioning of the patients. Therefore, the study emphasizes the need for alternative approaches to address emotional concerns in patients with metastatic breast cancer. Importantly, the study did not provide information about the influence of exercise on therapy compliance.

A second study presented in San Antonio by Kelly Metcalfe investigated the impact of surgical treatment on women with breast cancer and a BRCA1 pathogenic variant. The analysis included 2,482 participants from 22 centers across 11 countries. Surgical options were breast-conserving therapy (852 patients), unilateral mastectomy (1,141 patients), and bilateral mastectomy (489 patients). The study found that 11.5% of participants developed contralateral breast cancer with a higher incidence in the breast-conserving therapy and unilateral mastectomy groups. Those who developed contralateral breast cancer were twice as likely to die. The 15-year breast cancer-specific survival rates were 86.2% for breast-conserving therapy and 88.7% for bilateral mastectomy. However, bilateral mastectomy did not significantly reduce mortality compared to breast-conserving therapy. Univariate analysis suggested lower survival with unilateral mastectomy compared to breast-conserving therapy, but this difference did not hold in multivariate analysis. Potential biases included a higher disease burden in the mastectomy group. The study emphasizes the need for longer follow-up and future research with newer treatments and oophorectomy considerations. It also highlights potential biases in the comparison groups, and further research could benefit from comparisons with a non-carrier population.

Matteo Lambertini presented findings from an international retrospective cohort study that delved into the implications of pregnancy after breast cancer in young women carrying germline BRCA pathogenic variants. With more than 12% of young women with breast cancer carrying BRCA1 or BRCA2 pathogenic variants, the study aimed to shed light on the safety and consequences of conceiving post-breast cancer treatment within this specific demographic. This multicenter study, conducted across 72 centers, encompassed 4,732 patients, with over 600 of them experiencing at least one pregnancy. The primary objectives were twofold: to ascertain the cumulative incidence of post-breast cancer pregnancies and to explore the potential prognostic impact of such pregnancies on disease-free survival. Key findings from the study included a cumulative incidence of pregnancy at 22% after 10 years, with a median time from breast cancer diagnosis to conception of 3.5 years. Notably, patients with hormone receptor-positive breast cancer exhibited a significantly lower cumulative incidence, coupled with a lengthier time to conception. Crucially, the study investigated the prognostic impact of post-breast cancer pregnancies. Encouragingly, pregnancy was not associated with shorter DFS, with a hazard ratio of 0.99 and a p-value of 0.9. Additionally, breast cancer-specific survival and overall survival demonstrated significantly improved outcomes for young BRCA carriers who experienced a pregnancy after breast cancer. An intriguing observation emerged among BRCA2 carriers, suggesting a potential association between pregnancy and adverse disease-free survival outcomes. Possible explanations for this observation were explored, including the higher prevalence of hormone receptor-positive status in BRCA patients and its potential correlation with endocrine therapy outcomes. In summary, the study provides substantial support for the safety of post-breast cancer pregnancies in young women with BRCA pathogenic variants, revealing no heightened risk of relapse.

Hatem Azim presented a study on fertility preservation and assisted reproductive technologies (ART) in breast cancer patients who interrupted endocrine therapy for pregnancy attempts. Building on the POSITIVE trial, it showed that temporary endocrine therapy interruption did not increase recurrence risk. Of 561 patients, 273 had no menstruation at enrolment; 94 recovered menstruation, and 74 reported at least one pregnancy after stopping endocrine therapy. Younger age correlated with pregnancy likelihood, regardless of therapy type. Half underwent fertility preservation at diagnosis, often using ovarian stimulation. After enrolment, 43% used ART, primarily ovarian stimulation for IVF or embryo transfer. Ovarian stimulation wasn’t linked to recurrence after three years, supporting the safety of pregnancy attempts in this setting.

References:

May A. et al., Effects of a structured and individualized exercise program on fatigue and health-related quality of life in patients with metastatic breast cancer: the multinational randomized controlled PREFERABLE-EFFECT study -SABCS 2023, #GS02-10

Metcalfe K. et al., Surgical Treatment of Women with Breast Cancer and a BRCA1 Mutation: An International Analysis of the Impact of Bilateral Mastectomy on Survival – SABCS 2023, #GS02-04

Lambertini M. et al., Pregnancy after breast cancer in young women with germline BRCA pathogenic variants: results from an international cohort study – SABCS 2023, #GS02-13

Azim H. et al., Fertility preservation and assisted reproductive technologies (ART) in breast cancer (BC) patients (pts) interrupting endocrine therapy (ET) to attempt pregnancy – SABCS 2023, #GS02-11