This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Radiotherapy Pa 1, Subject name: Radiology
Intracranial Irradiation most commonly leads to deficiency of 
Select and explain. 
A. TSH, B. ACTH, C. PROLACTIN, D. GROWTH HORMONE
D: GROWTH HORMONE
Answer: D: GROWTH HORMONE 
Explanation: *Growth Hormone is most radiosensitive pituitary hormone and intracranial irradiation leads to hypopituitarism mainly due to hypothalamic damage rather than pituitary damage *Least radiosensitive pituitary hormone is TSH