SRS treatment has many advantages and has gradually become an important treatment for pituitary adenomas. Cushing’s disease and acromegaly were the first pituitary adenomas to be treated with SRS.
After 1989, due to the application of MRI stereotactic technique, the identification of fine structures has been enhanced, and not only the pituitary adenoma can be more correctly localized, but also the higher dose irradiation of the optic path can be avoided. The radiosensitivity of acromegaly and PRL adenoma is higher than that of Cushing’s disease, and that of children is higher than that of adults. Hu satellite, Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University 1. Non-secretory adenoma: moderately sensitive to radiation, better efficacy, visible tumor tissue destruction and volume reduction.
Indications for radiotherapy: ① those who are not completely removed by surgery; ② those who are old and have poor health or have important organ insufficiency and cannot tolerate surgery; ③ those who are unwilling to accept surgical treatment; ④ those who have recurrence after surgery, especially multiple recurrences, as long as the optic path does not descend into the pterion.
Complications of radiotherapy: ① hypopituitarism (about 1/3); ② radiation necrosis, mainly damage to the visual pathway; ③ other complications such as intratumoral hemorrhage, seizures, extraocular muscle paralysis, empty pterygoid saddle syndrome, and delayed hypothalamic damage in some patients; ④ pituitary adenoma that grows into the pterygoid sinus, and cerebrospinal fluid nasal leakage after radiotherapy due to tumor volume reduction.
2.Secretory pituitary adenoma: Generally, radiotherapy is more effective for those with mild endocrine hyper-symptom and low hormone elevation level. The effect of radiotherapy is usually maintained for 1 to 2 years. The effect of radiotherapy for TSH adenoma has been reported to be 31%. It is generally believed that the main treatment for secretory pituitary adenoma is surgery, followed by radiotherapy with a radiation dose of 45-50 Gy. When treated with SRS, the lowest peripheral dose to control the growth of pituitary adenoma may be 12 Gy. It is generally believed that the peripheral dose should be 12-14 Gy for the purpose of controlling the growth of adenoma, and at least 20 Gy for the purpose of controlling endocrine disorders.