Abstract
Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer associated with poor survival, in which adjuvant systemic treatments are limited to chemotherapy. Due to competing mortality risks and comorbidities, older patients with TNBC are often undertreated with adjuvant chemotherapy, and clinical trials on this problem are scarce, despite a growing patient population. This study aimed to assess outcomes for patients aged 70 years and older with TNBC with or without chemotherapy in a national population-based registry, to provide information that can assist in treatment decisions for these patients. In this population-based registry study, data on all patients aged 70 years and older diagnosed with primary early TNBC (larger than 5 mm in diameter and without distant metastasis) and surgically treated between Jan 1, 2009, and Dec 31, 2016, were retrieved from the Swedish National Breast Cancer Register, the Swedish Patient Register, and the Swedish Cause of Death Register. Patients with incomplete data (on oestrogen receptor, progesterone receptor, or human epidermal growth factor receptor 2 status, surgical procedure in the breast, or information about chemotherapy) were excluded. A propensity score-matched (PSM) model was used to examine the outcomes of adjuvant chemotherapy on 5-year breast cancer-specific survival (BCSS) and 5-year overall survival (OS), adjusted for age, tumour size, tumour grade, nodal status, and comorbidities. Of 1130 women eligible for analysis, 368 (32·6%) received adjuvant chemotherapy, 45 (4·0%) received neoadjuvant treatment, and 717 (63·5%) did not receive chemotherapy. 5-year BCSS was significantly improved in patients who received adjuvant chemotherapy (85% [95% CI 81-89]) compared with patients who did not receive chemotherapy (68% [64-72]; p<0·0001). A similar benefit was observed in 5-year OS (79% [95% CI 75-84] vs 49% [45-53]; p<0·0001). In our PSM analysis, 5-year BCSS in patients treated with adjuvant chemotherapy was 83% (95% CI 78-89), versus 73% (67-80; p=0·014) in patients not treated with chemotherapy. 5-year OS in patients treated with adjuvant chemotherapy was 75% (95% CI 69-82), versus 63% (57-71; p=0·029) in patients who did not receive chemotherapy. In this PSM registry analysis of surgically treated female patients aged 70 years and older with TNBC without distant metastasis, we identified a significant benefit both in 5-year BCSS and 5-year OS with adjuvant chemotherapy versus no chemotherapy, which persisted when adjusting for age and comorbidities. These results underline the importance of considering adjuvant chemotherapy in older patients. Knut and Alice Wallenberg Foundation, Assar Gabrielsson Foundation.
Highlights
In 2018, approximately 2·1 million women worldwide were newly diagnosed with breast cancer, accounting for almost 1 in 4 cancers among women. 627 000 deaths related to breast cancer were reported, comprising 15% of all cancer-related deaths in women.[1,2] The incidence of breast cancer is related to age; in the USA in 2019, 59% of all breast cancer cases were diagnosed in women aged 60 years and older.[3]
Interpretation In this propensity score-matched (PSM) registry analysis of surgically treated female patients aged 70 years and older with Triple-negative breast cancer (TNBC) without distant metastasis, we identified a significant benefit both in 5-year breast cancer-specific survival (BCSS) and 5-year overall survival (OS) with adjuvant chemotherapy versus no chemotherapy, which persisted when adjusting for age and comorbidities
We identified a knowledge gap regarding the use of chemotherapy in older women with early triple-negative breast cancer (TNBC), with these patients rarely being included in randomised clinical trials
Summary
In 2018, approximately 2·1 million women worldwide were newly diagnosed with breast cancer, accounting for almost 1 in 4 cancers among women. 627 000 deaths related to breast cancer were reported, comprising 15% of all cancer-related deaths in women.[1,2] The incidence of breast cancer is related to age; in the USA in 2019, 59% of all breast cancer cases were diagnosed in women aged 60 years and older.[3]. In 2018, approximately 2·1 million women worldwide were newly diagnosed with breast cancer, accounting for almost 1 in 4 cancers among women. 627 000 deaths related to breast cancer were reported, comprising 15% of all cancer-related deaths in women.[1,2] The incidence of breast cancer is related to age; in the USA in 2019, 59% of all breast cancer cases were diagnosed in women aged 60 years and older.[3] Modern treatment for breast cancer is highly individualised. Triple-negative breast cancer (TNBC) is a heterogeneic histological subtype that lacks oestrogen receptor (ER) and progesterone receptor (PR) expression, and HER2 is not amplified or overexpressed. TNBC consists of different subtypes, the most common being basal-like.[4] The lack of biomarkers limits the available systemic
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
