How long does radiotherapy take to work for a pituitary tumour?

Radiotherapy is directed at the tumour or the area where tumour cells need control. Its biological effect develops after treatment, and a pituitary tumour may remain visible on a scan even when treatment is controlling its activity. A scan alone therefore cannot answer every question about response.

Because the pituitary gland controls hormones, follow-up may include blood tests for hormone levels as well as checks on headaches, vision and other symptoms. Hormone changes can require replacement treatment or adjustment of existing medicines. The schedule depends on the tumour type, its size and its relationship to the optic nerves and nearby structures.

Keep every imaging, blood-test and endocrinology appointment, even if you feel well. Take medicines exactly as prescribed and keep an updated list of doses. Tell your team about worsening headache, changes in vision, unusual thirst or urination, marked tiredness, vomiting or new weakness.

Ask which symptoms should trigger a same-day call and when the next scan or hormone panel is planned. Do not stop steroid or hormone replacement medicine without medical advice. More information about treatment delivery is available in [Radiotherapy](/treatments/radiation-oncology/radiotherapy/).

Seek urgent medical help for sudden loss or marked worsening of vision, a severe new headache, repeated vomiting, confusion, collapse or new weakness. Contact your treatment team promptly for persistent vomiting, major changes in thirst or urination, or symptoms suggesting that hormone replacement is not adequate.

Ask: What is the goal of radiotherapy for my tumour? Which hormones will be monitored? When should I expect the first scan? Could I need hormone replacement now or later? What vision changes require urgent review?