2024 Top Story in Metastatic Breast Cancer: Epidemiology of Early vs Late Recurrence Among Women With Early-Stage ER+ Breast Cancer

This article provides valuable information that will be helpful on many levels, such as in conversations with individual patients about recurrence risk and in promoting additional studies that would include an analysis of HER2 status.^1,2 The degree of positivity is an important element to factor in this information, given that even a 5% positivity for the estrogen receptor is considered sufficient to be classified as "positive." We celebrate when a patient has higher than 90% positivity because we feel confident that hormonal therapy will be of great benefit to her in preventing recurrence. We know from this study and other studies that women with HR+/HER2− early-stage breast cancer are at risk of a distant recurrence 5 years following diagnosis. This is a difficult discussion to have with a patient given that we have likely been very upbeat about her early stage I or II diagnosis and the favorable prognostic factors of ER and HER2. Subsequently, just when a patient begins to regain confidence in her health status, she may be stunned to learn that her bone pain is caused by metastatic disease.

We also do not know if the patients in this study were religious in taking their hormonal therapy as prescribed. From prior studies conducted regarding treatment adherence, we know that patients may initially take their medications; however, owing to side effects and the realization that they will be taking these drugs for 5 or more years, they may personally decide to take the medication every other day or not at all. They were compliant with surgery, chemotherapy, and/or radiation therapy; however, now that the acute treatment is complete and the medical oncologist congratulates them on completing their treatment while handing them a prescription for hormonal therapy, it may send the wrong message. Additionally, their doctor is not seeing them as frequently as before, which may also send a message to not worry as they are fine now. The patient had a foxhole religion during acute treatment, focused on saving her life. Now that it appears that this has been accomplished, having to take a pill daily for a long time, associated with unpleasant side effects, can result in not adhering to hormonal therapy as prescribed.

Therefore, educating the patient and her family caregiver about the importance of hormonal therapy being key to the prevention of recurrence must be emphasized. We must tell the patient to be honest with us, as we have strived (I hope) to always be truthful with her. Further, ask the patient during her subsequent appointments: "Are you taking your hormonal therapy as prescribed?" Since if you simply ask, "Are you taking your hormonal therapy?" she will likely respond, "Yes," but will not tell you that she only takes it a few times a week. There have been no studies to determine whether such a patient-driven treatment plan works at all. Additionally, patients do not necessarily discuss with their oncologist the side effects (such as sexual dysfunction) that are disrupting their quality of life and, potentially, that of their spouse/partner.  Usually, when a patient receives her first prescription for hormonal therapy, she is alone, without her family caregiver (for example, her spouse/partner) to learn the purpose of this medicine and the importance of taking it as prescribed. Spouses can even be a primary driver of why a patient stops taking her drug since some side effects are "shared," like low libido and sexual dysfunction.

So, a relook at these data could be helpful, as well as measuring data associated with the percentage of ER positivity, determining the HER2 score, and factoring in the recent classification of HER2-low status. Further, consider asking patients if they did or did not adhere to daily hormonal therapy as prescribed. By doing so, we can clearly learn much more.