Five years or ten? How long you actually need hormone therapy

Five years of hormone therapy has long been the standard for hormone-sensitive early breast cancer. Studies have shown that continuing for longer, up to about ten years in total, further lowers the chance of the cancer returning for some women, particularly those whose cancer had higher-risk features such as lymph node involvement. For lower-risk cancers, the extra benefit is small and may not outweigh several more years of side effects.

Why hormone-sensitive cancers need long treatment

Hormone-sensitive breast cancer can return many years after diagnosis, sometimes a decade or more later. Hormone therapy keeps working for as long as it is taken, which is why extending it can help some women.

How the decision is usually made

Around the time you approach five years, your oncologist reviews your original cancer features, how well you have tolerated treatment, your bone health and your own preferences, and discusses whether to stop or continue.

When stopping at five years is reasonable

For small, node-negative, lower-grade cancers, or when side effects have been difficult, stopping at five years is often a sensible choice. The decision is personal and should be revisited with your oncologist.

The extra benefit of continuing beyond five years is real but modest for most women. The longer you take hormone therapy, the more the side effects matter, because they are lived with every day for years. That is why this is genuinely a shared decision rather than a fixed rule.

Many women stop early without telling anyone

Studies show that a large share of women stop hormone tablets early, often because of side effects. If you are struggling, tell your team. Switching tablets, managing symptoms or planning a shorter course is far better than stopping quietly.

The benefit is spread over many years

Extending treatment lowers the chance of recurrence gradually over the following years. You will not feel the benefit directly, which can make continuing harder to justify on difficult days.

Evidence keeps developing

Research continues into which women gain most from longer treatment, and tests that predict late recurrence are being studied. Your oncologist can tell you what current evidence suggests for you.

What this page cannot tell you

It cannot tell you whether to stop or continue. Ask your oncologist how much longer treatment would help in your situation.

Reaching five years is a milestone. Going into the review prepared helps you make a decision you feel comfortable with.

Gather your information

Bring your original pathology report, a list of side effects you have had, your latest bone density result and any other health changes.

Ask the key questions

Ask how much continuing would lower your chance of recurrence, which tablet you would take, and how side effects and bone health would be managed.

Say what matters to you

Whether it is avoiding side effects, planning a pregnancy or doing everything possible to prevent recurrence, your priorities are a legitimate part of the decision.