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What is Perineural spread is seen in: and explain in detail?
Perineural spread is seen in

Mucoepidermoid carcinoma
Keratoacanthoma
Adenoid cystic carcinoma

Keratoacanthoma on occasion may invade perineural spaces, but this does not adversely affect the biologic behavior of the lesion; neither can it be used as a distinguishing characteristic between keratoacanthoma and epidermoid carcinoma.
Ref- Shafer's 7th Ed  P: 236