Advanced breast cancer patients living longer thanks to improvements in treatment and care

Lisbon, Portugal: People diagnosed with advanced breast cancer in 2025 can expect to live for an extra six or seven months, compared to the average survival time for patients diagnosed in 2011, according to a major study of patient data in the US presented at the Advanced Breast Cancer Eighth International Consensus Conference (ABC8). [1]

For some types of advanced breast cancer, the average improvement in survival is ten months or more; however, the data also show a smaller increase in survival for so-called triple negative advanced breast cancer.

Researchers say the increase in survival time coincides with the availability of more effective treatments for advanced breast cancer, as well as wider improvements in diagnosis and quality of care.

The research was led by Professor Fatima Cardoso, President of the Advanced Breast Cancer Global Alliance (ABC Global Alliance), Lisbon, Portugal, and Dr Thibaut Sanglier, Senior Principal Data Scientist at F. Hoffmann-La Roche, Basel, Switzerland.

Professor Cardoso said: “Survival time for patients with advanced breast cancer, where the cancer has spread to other parts of the body, is much lower compared to early breast cancer. The major treatments for this stage of breast cancer are systemic therapies, like hormone therapy, chemotherapy and targeted therapy, that aim to kill cancer cells wherever they are growing in the body.

“In the last 15 years, we have seen a number of new systemic therapies developed and become available to some patients. We wanted to take a look at whether improvements in treatment are making a real difference to survival time for patients, and whether some groups of patients are doing better or worse than others.”

The study included more than 60,000 patients who were treated for metastatic breast cancer in the US since 2011. Researchers broke the data down into blocks of three years, so they could compare average survival over time.

They also broke the data down into the main subtypes of breast cancer according to whether or not the tumours are fuelled through the human epidermal growth factor receptor 2 (HER2+) and whether the tumours are fuelled through the oestrogen and progesterone hormone receptors (HR+). Triple-negative breast cancers are tumours that do not have any of these receptors (HER2, or oestrogen or progesterone receptors).

Overall, the average survival for patients who began systemic treatment between 2011 and 2013, was 27.5 months. This increased over the following years and, for patients who began treatment between 2020 and 2022, average survival time increased to 34.3 months.

Patients with HER2+/HR+ advanced breast cancer had the longest survival times at the start of the study period (42 months on average), and this continued to improve over the following years (53.1 months by end of the study period). In patients with HER2+/HR- cancers, the improvement in survival time has been greater (33.4 months to 52 months), especially after 2014-2016.

Survival times for patients with HER2-/HR+ have increased more gradually from 31.7 months to 39.2 months.

Survival time at the start of the study period was lowest for patients with triple negative breast cancer (11.2 months). This remained low for most of the study period, but has improved modestly for patients who began treatment in 2020-2022 (13.2 months).

Professor Cardoso said: “Alongside improvements in diagnosis and quality of care for patients with advanced breast cancer, we’ve seen several new treatments targeted towards breast cancer in recent years. Examples are the treatments targeting the HER2 receptor, that have changed the natural history of this subtype of breast cancer, and a group of medicines called CDK4/6 inhibitors for the hormonal-dependent breast cancer subtype.

“More recently, some much-needed new therapies for triple negative breast cancer, such as immune checkpoint inhibitors, PARP inhibitors and antibody-drug conjugates, have been developed and approved. We expect that their positive effect on survival will become more visible in the next few years.

“We knew that some of these treatments prolong life for patients treated in clinical trials, but this study suggests that they are also effective in ‘real-world’ patients who can access them, with important improvements in survival. The survival improvements seen in this study are likely to be similar in other high-income countries, where innovative therapies are available. However, a major hurdle is the cost of all these agents, rendering them unaffordable to many patients worldwide. One of the findings of the new ABC Global Decade Report 2015-2025 is that inequalities, between and within countries, have increased in the last decade.

Professor Eric P. Winer is an Honorary Chair of ABC8 and Director of the Yale Cancer Center, USA, and was not involved in the research. He said: “These results are positive for people who are being diagnosed with advanced breast cancer today; they can expect to live longer, compared to patients diagnosed ten or even five years ago. However, results have improved more for some types of breast cancer than others, and we still have a tremendous amount of work ahead. The outcome for many patients, such as those with triple negative breast cancer, is still highly variable.

“It’s important to say that these are patients treated in the United States, where patients often have better access to some of the newest therapies. This study shows that research and development of new treatments can make a real difference to patients’ lives. Now we need to make sure that advanced breast cancer patients can access and benefit from these treatments wherever they are in the world.”

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[1] Abstract no: OR61, ‘Evolution of the overall survival of patients with ABC from 2011 to 2025: an analysis of electronic health records in the U.S.’, by Thibaut Sanglier et al, in ‘Best Abstract Presentation’ session, 15.10-15.50 hrs GMT, Thursday 6 November.

Funding: ABC Global Alliance and F. Hoffmann-La-Roche