Removing Part of Breast Better than Mastectomy in Older Cancer Patients, Study Finds

Removing Part of Breast Better than Mastectomy in Older Cancer Patients, Study Finds

Breast conserving surgery combined with radiation, a treatment option called breast conserving therapy (BCT), is better than mastectomy in a subset of breast cancer patients, particularly older ones, according to a study.

MirelleLagendijk, MD, presented the research, “Breast conserving therapy and mastectomy revisited: Breast cancer-specific survival and the influence of prognostic factors in 129,692 patients,” at the European Cancer Congress 2017 Jan. 27-30 in Amsterdam. Lagendijk is with the Erasmus MC Cancer Institute‘s Department of Surgical Oncology in Rotterdam.

In the past, randomized trials showed that BCT and mastectomy produced similar survival outcomes. But such trials often excluded older patients or those with diseases besides breast cancer. Including such patients in large, population-based groups could better represent patient outcomes, researchers decided.

Breast conserving therapy involves removing part of a breast that has a tumor. Mastectomy involves removing the entire breast.

Professor Sabine Siesling led a group that conducted a population-based study assessing the survival of all non-metastatic breast cancer patients in the Netherlands Cancer Registry who had been diagnosed between 1999 and 2012. Siesling is with the University of Twente in Lagendijk and the Netherlands Comprehensive Cancer Organisation (IKNL). His colleagues in the study were from other hospitals.

The nearly 130,000 breast cancer patients included in the research were divided into two groups: those diagnosed between 1999 and 2005, and those diagnosed between 2006 and 2012.

In each cohort, researchers studied the influence of various factors on patients’ survival. They included age, stage of the cancer, comorbidity — or presence of another disease besides breast cancer — hormonal and HER2 receptor status, and adjuvant systemic therapy.

“We looked at two different groups in order to allow us to compare long-term outcomes in a more historical versus a more recent cohort, evaluating patients that had been able to benefit from more sophisticated diagnostics and therapies. A considerably superior survival, both specific to breast cancer and from any cause of death, was found for BCT in the early stage T1-2N0-1M0 cancers in both time cohorts,” Siesling said in a news release.

T1-2N0-1M0 cancers are those that have not spread to other areas of the body. Researchers discovered that patients with these cancers who were older than 50, had a comorbidity, or had not received chemotherapy could survive better when treated with BCT than with a mastectomy.

“Although this study is based on retrospective data with much detailed data, and residual confounding factors cannot be ruled out completely, we believe that this information will have potential to greatly improve shared treatment decision-making for future breast cancer patients in those aged over 50 years and those with comorbidity,” Siesling said.

“However, we would like to emphasise that these results do not mean that mastectomy is a bad choice. For patients for whom radiotherapy is not suitable or feasible due to social circumstances, for whom the risk of late side effects of radiotherapy is high, or who have the prospect of a poor aesthetic outcome following BCT, a mastectomy may still be the preferable treatment option. Our study showed that BCT is at least as good as mastectomy and that some patients might benefit more than others from BCT in the future,” he concluded.