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
A 56 year old smoker presented with swelling over parotid region. Histology shows papillary structures composed of granular eosinophilic cells, cystic changes, and mature lymphocytic infiltration which is pathognomonic of Wahin tumor. Treatment of choice for wahin's tumor is: 
Select and explain. 
A. Complete excision of the affected poion of the gland with uninvolved margins, B. Enucleation, C. Radiotherapy, D. Injection of a sclerosant agent
A: Complete excision of the affected poion of the gland with uninvolved margins
Answer: A: Complete excision of the affected poion of the gland with uninvolved margins 
Explanation: Wahin tumor is also known as papillary cystadenoma lymphomatosum and is found almost in the parotid gland. It is characterized histologically by papillary structures composed of double layers of granular eosinophilic cells or oncocytes, cystic changes, and mature lymphocytic infiltration. It arises from the ectopic ductal epithelium. This tumor is more commonly seen in males in the fifth to seventh decades of life and there is an associated risk with smokers. The diagnosis of Wahin tumor is based on histologic findings. The treatment is complete excision of the affected poion of the gland with uninvolved margins. Ref: Butt F.Y. (2012). Chapter 18. Benign Diseases of the Salivary Glands. In A.K. Lalwani (Ed), CURRENT Diagnosis & Treatment in Otolaryngology--Head & Neck Surgery, 3e.