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What is Carcinoma known for perineural invasion is and explain in detail?
ADENOID CYSTIC CARCINOMA (CYLINDROMA) It is a slow-growing tumour but infiltrates widely into the tissue planes and muscles. It also invades perineural spaces and lymphatics and thus causes pain and VIIth nerve paralysis. It can metastasize to lymph nodes. Local recurrences after surgical excision are common and can occur as late as 10-20 years after surgery. Distant metastases go to the lung, brain and bone. Treatment is radical parotidectomy with largest cuff of grossly normal tissue around the boundaries of the tumour. Radical neck is not done unless nodal metastases are present. Postoperative radiation is given if margins of the resected specimen are not free of tumour. 2nd most common Malignancy of salivary glands after mucoepidermoid carcinoma Advanced tumours may present with pain or nerve paralysis, as it has a propensity to invade peripheral nerves Histology of Adenoid cystic carcinoma Ref : Diseases of ENT by Dhingra 6th edition Pgno : 235