This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Plastic & Reconstructive Surgery, Subject name: Surgery
Cock's peculiar tumor is 
Select and explain. 
A. Basal cell CA, B. Squamous cell CA, C. Ulcerated sebaceous cyst, D. Cylindroma
C: Ulcerated sebaceous cyst
Answer: C: Ulcerated sebaceous cyst 
Explanation: Ans is 'c' i.e. Ulcerated sebaceous cyst Repeat from May 04Cocks peculiar tumor is actually a complication of sebaceous cyst.- When the sebaceous cyst of the scalp ulcerates excessive granulation tissue forms resembling fungating epithelioma. This is called cock's peculiar tumor.Also know these termsCylindroma-A malignant epithelial tumour also k/a Turban tumorKnown as cylindroma because of histological appearancePilomatrixoma (Calcifying epithelioma of Malherbe) -It is a benign hair follicle derived tumour.Pott's puffy tumour -It is osteomyelitis of the skull associated with subperiosteal swelling and edema.