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: Surgery
Which of the following is not an indication of radiotherapy in Pleomorphic adenoma of parotid? 
Select and explain. 
A. Involvement of deep lobe, B. 2nd histologically benign recurrence, C. Microscopically positive margins, D. Malignant transformation
B: 2nd histologically benign recurrence
Answer: B: 2nd histologically benign recurrence 
Explanation: Ans. is none or (b) is the best option The above mentioned books mention the following indications of postop radiotherapy in Pleomorphic adenoma of parotid. Indications for postop radiotherapy in Pleomorphic adenoma Involvement of the deep lobe of the parotid Recurrent lesions Large (> 5 cm) lesions, which may not allow complete surgical excision with adequate margins. Microscopically positive margins after surgical resection. Malignant transformation within a predominantly benign tumor. So all the given options are indications for post op radiotherapy, but if we have to choose one option we would go for option (b) i.e. 2nd histologically benign recurrance, as its the most controversial one.