Improving Adherence to Endocrine Therapies: The Role of Advanced Practice Nurses

September 1, 2006

With the trend toward the use of oral rather than intravenous therapies for cancer, nonadherence to treatment has become an increasing concern. Advanced practice nurses are in a good position to assess and monitor adherence to oral endocrine therapies. Research on adherence has been limited; to date there are no specific published guidelines for ensuring adherence to endocrine regimens. However, studies have identified many factors that may lead to nonadherence, including demographic, social, and psychological characteristics of the patient; characteristics of the disease and the treatment regimen; and the nature and quality of the patient/clinician relationship. These factors provide a framework that advanced practice nurses can use to identify potential problems and to work collaboratively with patients.

Nonadherence to therapy, instructions, or follow-up recommendations has been a commonly recognized problem for many disease states. Even posttransplant regimens that are critical to the success of the transplant, and thus the life of the patient, are still difficult for some patients to follow.[1] As noted in the article by Kelly and Agius, the literature is replete with documentation of the universality of nonadherence and the tremendous negative impact this problem has on patient outcomes. In their article, the authors have presented a discussion of this issue from the perspective of oral cancer treatment, in particular endocrine treatments for breast cancer, and discuss interventions to attempt to improve adherence.

Widespread Problem

Nonadherence to active cancer therapy is more widespread and troubling than only the issue with oral therapeutics. For example, in the adjuvant setting, such as for colon cancer, Dobie et al[2] reported that 78.2% of patients completed therapy. In that study, treatment complications as well as factors noted by Kelly and Agius impacted adherence.

The chronic nature of cancer and cancer treatment regimens also contribute to the problem. Because of progress in treating metastatic cancers, multiple regimens are frequently offered sequentially over extended periods of time. Further, nonadherence to adjuvant therapy in particular will affect successful outcomes,[3] making the issue of nonadherence an urgent concern.


Toxicities and Adherence

As noted by the authors, adherence rates to oral regimens of any sort are far from desirable. While endocrine-based therapies for prevention or treatment (adjuvant or otherwise) may not appear to be associated with significant side effects in comparison with antineoplastic agents, these side effects can be troubling for patients nonetheless. These symptoms, primarily related to estrogen deprivation, are not trivial to the patient and interfere with many aspects of her life. The authors' approach of developing a collaborative relationship would likely help address that issue by acknowledging the patient's difficulty. The patient then will not perceive her concerns as being discounted. As oral chemotherapeutics become more common, openly addressing the issues of toxicity and management may improve compliance.

Others have noted that toxicities of treatment regimens influence adherence.[4,5] Experientially, most providers would likely concur. It takes a great deal of discipline for a patient to open a bottle at home and take a medication that is likely to make them feel in some way unpleasant or even overtly ill. Attention to ameliorating toxicities and assisting the patient in managing side effects should then also improve adherence. Factor into that prolonged treatment, and the issues the authors highlight-knowledge, belief systems, and cost-become even more important.

As described in this article, for breast cancer endocrine treatment the patient must believe not only that there is a real problem worth treating (such as the risk of breast cancer recurrence), but also that the medication will take care of it. Assisting the patient in dealing with this problem will also not be a one-time interaction. Patients will require coaching and encouragement along with reiteration of the purpose and worth of the therapy repeatedly through the course of care.


1. De Geest S, Dobbels F, Fluri C, et al: Adherence to the therapeutic regimen in heart, lung, and heart-lung transplant recipients. J Cardiovasc Nurs 20(5 suppl):S88-S98, 2005.

2. Dobie SA, Baldwin LM, Dominitz JA, et al: Completion of therapy by Medicare patients with stage III colon cancer. J Natl Cancer Inst 98(9):570-571, 2006.

3. Bernier J, Vermorken JB, Koch WM: Adjuvant therapy in patients with resected poor-risk head and neck cancer. J Clin Oncol 24(17):2629-2635, 2006.

4. Chen YM, Shus JF, Perng RP, et al: A randomized trial of different docetaxel schedules in non-small cell lung cancer patients who failed previous platinum-based chemotherapy. Chest 129(4):840-842, 2006.

5. Neymark N, Crott R: Impact of emesis on clinical and economic outcomes of cancer therapy with highly emetogenic chemotherapy regimens: A retrospective analysis of three clinical trials. Support Care Cancer 13(10):812-818, 2005.