This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
Prophylactic intracranial radiation is given in 
Select and explain. 
A. Small cell carcinoma, B. Testicular carcinoma, C. Breast carcinoma, D. Gastric carcinoma
A: Small cell carcinoma
Answer: A: Small cell carcinoma 
Explanation: This aggressive form of lung cancer most commonly occurs in smokers. It usually starts in the breathing tubes (bronchi) and grows very quickly, creating large tumours and spreading (metastasising) throughout the body.
Symptoms include bloody phlegm, cough, chest pain and shortness of breath.
Treatment includes surgery (for small tumours) as well as chemotherapy, sometimes in combination with radiation therapy.