When prostate cancer has spread outside the prostate but is still responding to hormone treatment, clinicians usually keep it under control with strong hormone‑blocking medicines. These treatments often work well for a time, but in some men, small areas of cancer can start to grow again.

The STAR‑TRAP study is testing whether adding a very precise type of radiotherapy—called SBRT (Stereotactic Body Radiotherapy)—can help treat these growing spots.

If you take part, you’ll stay on your usual hormone treatment. Then, you’ll be randomly placed into one of two groups:

• Hormone treatment only, or
• Hormone treatment plus SBRT

SBRT is a highly focused form of radiotherapy. It targets only the cancer spots and aims to limit effects on healthy tissue. Treatment is usually given in 3–5 short sessions.

The hope is that by directly treating these active spots with SBRT, we can:

• Keep the cancer controlled for longer
• Delay the need for stronger treatments like chemotherapy
• Help you maintain a better quality of life

The study follows participants for around three years to see how long the cancer stays stable, when new treatments are needed, and how people feel during and after treatment.

In simple terms: STAR‑TRAP is testing whether adding targeted radiotherapy to standard hormone treatment can give men with advanced prostate cancer more time before the disease progresses—without causing too many extra side effects.