2 November 2020

Endocrine therapy is a key component of breast cancer treatment for those with both early stage and metastatic hormone receptor-positive disease. However, side effects can be significant, and many patients do not complete recommended therapy. Our recent study* showed that over 90% of women and men prescribed endocrine therapy experience treatment-related side effects, and approximately 30% discontinue treatment early. 

Musculoskeletal issues such as bone pain, joint pain and stiffness, and bone loss (osteopenia and osteoporosis) are among the most common side effects related to aromatase inhibitors (AIs). A recent review by Gupta et al* discussed several side effect mitigation strategies and the evidence behind them. The most effective included exercise including yoga, acupuncture, duloxetine (brand name Cymbalta), treatment breaks, changing to a different AI, or changing from an AI to tamoxifen.

In my accompanying editorial*, I noted that there are barriers to successfully managing side effects, including cost, access and adherence to structured exercise programs and acupuncture, reluctance to add a new medication which comes with its own side effects, and anxiety regarding treatment breaks both on the part of the patient and their oncologist. In addition, none of the side effect treatments have been found to be universally effective. In fact, in our survey, only 41% of respondents noted that any side effect management was effective.

Clearly a new approach is needed, focusing on open and active communication between the patient and his or her oncologist. Endocrine therapy is often the “last” phase of breast cancer treatment, and patients may not remember conversations held at the time of diagnosis regarding benefits and side effects of endocrine therapy. Re-visiting the role of endocrine therapy, along with associated side effects and management techniques should occur before treatment. The absolute benefits of treatment should be clearly discussed – statements such as “this will reduce your risk of recurrence by 50%” are not meaningful unless a patient understands what her absolute risk of recurrence is – are we trying to reduce a 50% recurrence risk down to 25% or a 5% recurrence risk down to 2.5%? 

Common and expected side effects, such as bone and joint pains, hot flashes, cognitive dysfunction (commonly termed “chemo-brain”) and impact on sexual function should be discussed, along with the evidence-based strategies to help manage these symptoms. In our study, patients noted that peer support (such as an in-person or virtual support group) as well as a website that provided clear information about side effects and management would be helpful, but these were not often provided. Patients also noted that an in-person or virtual visit with their physicians to discuss side effects would be helpful – this should ideally occur within 4-6 weeks of treatment initiation so that issues and concerns can be promptly addressed. 5-10 years is a long time to take a medication that is having a significant impact on quality of life – it is important that patient concerns are heard and addressed at every visit. 

*If you are not able to access the full study and would like a copy, please email me: contact at drattai dot com