Breast Cancer Treatment Ends, But The Medication Questions Don’t

Completing chemotherapy or radiation is a milestone, but it does not necessarily mark the end of breast cancer treatment. For patients with hormone receptor–positive early-stage disease, endocrine therapy can continue for years after surgery, bringing medication decisions into everyday life long after infusion appointments end.¹

Breast Cancer Awareness Month offers an opportunity to recognize this less visible phase of care. Survivorship can overlap with ongoing anticancer treatment, and patients still need help understanding which symptoms warrant attention. The American Cancer Society/American Society of Clinical Oncology (ASCO) survivorship guideline recommends monitoring endocrine therapy adherence and addressing symptoms that affect quality of life.²

For pharmacists, a refill encounter can open a conversation that extends beyond whether a patient has enough tablets.

A Daily Prescription With a Long-Term Purpose

Adjuvant endocrine therapy reduces the risk of new or recurrent breast cancer. Depending on menopausal status and clinical circumstances, treatment can include tamoxifen, an aromatase inhibitor, or ovarian suppression. Evidence supports substantial benefits from treatment lasting 5 years or longer, although the regimen and duration require individualized decisions.¹

Pharmacists can reinforce why treatment continues when a patient feels well or has completed other therapies. Explaining its purpose also creates room to ask whether taking it has become difficult.

An open-ended question about the hardest part of treatment can be more informative than a yes-or-no adherence check. The goal is to identify a problem the care team can address, rather than interpret an unfilled prescription as a lack of motivation.²

Make Symptoms Part of the Medication Review

Persistent symptoms deserve assessment even when they are expected effects of treatment. Pharmacists can ask how symptoms affect daily activities and whether patients have changed how they take medication because of them. The survivorship guideline supports symptom evaluation alongside adherence counseling.²

For aromatase inhibitor–associated joint pain, randomized evidence provides one example of a management option. In SWOG S1202 (NCT01598298), duloxetine reduced average joint pain scores by 0.82 points more than placebo through 12 weeks (95% CI, −1.24 to −0.40; P = .0002). Adverse events of any grade occurred more frequently with duloxetine, at 78% versus 50%.³

That modest average benefit supports a discussion about suitability, not automatic prescribing. Pharmacists can help evaluate whether symptom relief justifies adding another medication and reassess tolerability after initiation. The trial studied aromatase inhibitor–associated pain; its findings should not be generalized to every survivorship complaint.³

A New Medication Can Change an Established Regimen

Medication reconciliation remains important after initial treatment. Some antidepressants can reduce tamoxifen’s effectiveness, including when prescribed to manage hot flashes. The National Cancer Institute also identifies potential interactions with nonprescription medications such as diphenhydramine and cimetidine.¹

Pharmacists should review newly added products against the current endocrine regimen and coordinate any changes with the prescriber. Patients should not independently discontinue an antidepressant or anticancer therapy. A medication that addresses one survivorship concern still needs to fit safely into the broader treatment plan.

Bone Health Needs a Follow-Through Plan

Cancer therapy can add to baseline fracture risk. ASCO’s osteoporosis guideline recommends assessing risk in adults with nonmetastatic cancer and obtaining bone mineral density testing when fracture risk is substantial. Nutrition and exercise should be optimized; when medication is indicated, bisphosphonates or denosumab at osteoporosis-indicated doses are preferred options.⁴

Pharmacists can help establish whether a bone health assessment has occurred and whether recommended treatment was started. Reviewing calcium and vitamin D intake can also identify gaps or unnecessary duplication. These conversations should connect patients with an individualized plan rather than default to supplements alone.⁴

Ask About the Symptoms Patients May Leave Unsaid

Vaginal dryness and pain with intercourse can require a private, direct invitation to discuss treatment. ACOG recommends nonhormonal approaches first for individuals with a history of estrogen-dependent breast cancer. Pharmacists can explain the difference between moisturizers used regularly and lubricants used for sexual activity.⁵

When nonhormonal treatment is inadequate, low-dose vaginal estrogen can be considered after discussion of risks and benefits, including for patients taking tamoxifen. For patients taking aromatase inhibitors, ACOG calls for shared decision-making involving the patient, gynecologist, and oncologist.⁵

The pharmacist’s role is to support that conversation without implying that every hormonal product is appropriate. Finishing an initial treatment course should come with a clear route back to care when medication concerns arise.^2,5

REFERENCES

1. Hormone therapy for breast cancer. National Cancer Institute. Updated September 23, 2026. Accessed October 16, 2026. https://www.cancer.gov/types/breast/treatment/hormone-therapy

2. Runowicz CD, Leach CR, Henry NL, et al. American Cancer Society/American Society of Clinical Oncology breast cancer survivorship care guideline. CA Cancer J Clin. 2016;66(1):43-73. doi:10.3322/caac.21319

3. Henry NL, Unger JM, Schott AF, et al. Randomized, multicenter, placebo-controlled clinical trial of duloxetine versus placebo for aromatase inhibitor-associated arthralgias in early-stage breast cancer: SWOG S1202. J Clin Oncol. 2018;36(4):326-332. doi:10.1200/JCO.2017.74.6651

4. Shapiro CL, Van Poznak C, Lacchetti C, et al. Management of osteoporosis in survivors of adult cancers with nonmetastatic disease: ASCO Clinical Practice Guideline. J Clin Oncol. 2019;37(31):2916-2946. doi:10.1200/JCO.19.01696

5. American College of Obstetricians and Gynecologists' Committee on Clinical Consensus - Gynecology. Treatment of urogenital symptoms in individuals with a history of estrogen-dependent breast cancer: clinical consensus. Obstet Gynecol. 2021;138(6):950-960. doi:10.1097/AOG.0000000000004601