Benefit of Endocrine Therapy in Elderly Women with Low Risk Hormone Receptor Positive Breast Cancer?

The gist: Recent research has found that certain women over 65 years old who have undergone breast conservation surgery for HR+ invasive breast cancer might benefit from modified treatment. Most women who undergo breast conservation surgery for HR+ invasive breast cancer are then treated with endocrine therapy and radiation therapy. However, researchers now say that elderly women might fare better with radiation alone after surgery. Specifically, the researchers say, women over 65 years old who are low-risk and have small tumors might benefit from the simpler treatment, avoiding any potential side effects of endocrine therapy.

“Treatment with endocrine therapy and radiation therapy as part of breast conservation is the current standard of care for women with hormone-receptor positive (HR+) invasive breast cancer. A new study by researchers at Fox Chase Cancer Center, however, shows that combination may not be necessary for all patient populations with the disease.

“The results, which Fox Chase researchers presented at the American Society for Radiation Oncology’s 56th Annual Meeting on Sunday, September 14, suggest that low-risk over 65 years old with small tumors may achieve comparable survival after treatment with adjuvant radiation therapy alone – without undergoing .

” ‘When they’re treated with adjuvant radiation therapy alone, with small, low risk tumors may have acceptable results,’ says Colin T. Murphy, MD, Radiation Oncologist at Fox Chase and lead author on the study. ‘Once their tumors start to get bigger, however, we identified an increasing risk for metastasis, and those people likely need to be on endocrine therapy…’ ”

” ‘In elderly women who have other medical problems, adding an additional medication for their breast cancer may not be feasible,’ says Dr. Murphy. ‘The question is, “for women with a low risk breast cancer, what’s the minimal extent of therapy we can deliver to minimally disrupt an elderly woman’s quality of life and still result in an acceptable cancer outcome?” ‘ ”

Study Identifies Clinicopathologic and Adjuvant Treatment Characteristics Linked to Very Low Risk of Local Recurrence After Breast-Conserving Surgery

The Gist: When a patient is given unnecessary treatment, there is a danger that it could cause unnecessary harm. A recent study found that some women aged 50 years or older who have stage I breast cancer might be able to forgo the radiation portion of the standard treatment for these women: breast-conserving surgery plus whole-breast radiation therapy. The researchers found that histologic grade, age, margin status, and use of endocrine therapy could potentially be used to identify women who might have a less than 5% chance of local recurrence after breast-conserving surgery, even without subsequent whole-breast radiation. These women may choose to have only surgery and avoid potentially harmful radiotherapy.

“Histologic grade, age, margin status, and use of endocrine therapy may identify a subset of women aged ≥ 50 with stage I breast cancer, who are at a very low risk of disease recurrence after breast-conserving surgery plus whole-breast radiotherapy, according to a study by Smith et al in the International Journal of Radiation Oncology • Biology • Physics.This finding suggests that these women may safely forgo radiotherapy, although further study is needed to support this approach.

“Breast-conserving surgery plus whole-breast radiation therapy is the current standard of care for women over 50 with stage I breast cancer. Previous studies have attempted to determine whether these patients could forgo whole-breast radiation therapy and still maintain lower rates of disease recurrence, but the results have been mixed. With that in mind, the investigators aimed to identify clinical and pathologic factors that might shed further light on the need for whole-breast radiation therapy after breast-conserving surgery within this patient population.

“The investigators conducted an analysis of an institutional database of patients with newly diagnosed breast cancer who underwent breast-conserving surgery and whole-breast radiotherapy. Over half of the patients received adjuvant systemic therapy, which was categorized as endocrine therapy alone, chemotherapy alone, or both endocrine therapy and chemotherapy. The primary outcome was local disease recurrence in the ipsilateral breast.”