<prompt> Cocks peculiar tumour is -An infected sebaceous cystA malignant tumour of the scalpA metastatic lesion of the scalpAn indicator of underlying osteomyelitis  <response>: Ans. a An infected sebaceous cyst Cocks peculiar tumour 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 cocks peculiar tumour. Also know these terms Cylindroma? - A malignant epithelial tumour also ka Turban tumor - Known as cylindroma because of histological appearance Pilomatrixoma Calcifying epithelioma of Malherbe ? - It is a benign hair follicle derived tumour. Potts puffy tumour ? It is osteomyelitis of the skull associated with subperiosteal swelling and edema. 