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What is Perinerual spread is seen in: and explain in detail?
Ans: A (Adenoid cystic carcinoma) Ref: Robbins and Comm Pathologic Basis of Disease, 8th editionExplanation:"Although slow growing, adenoid cystic carcinomas are relentless and unpredictable tumors with a tendency to invade perineural spaces" Ref: RobbinsAdenoid cystic carcinomaIt is a relatively uncommon tumor.Found in the minor salivary glands in 50% of cases (especially in Palate ).Among the major salivary glands, the parotid and submandibular glands are the most common locations.MorphologySmall, poorly encapsulated, infiltrative, gray-pink lesions.Microscopically, small cells having dark, compact nuclei and scant cytoplasm.These cells tend to be disposed in tubular, solid, or cribriform patterns reminiscent of cylindromas arising in the adnexa of the skin.The spaces between the tumor cells are filled with a hyaline material which represents excess basement membrane,Has a tendency to invade perineural spaces and are recurrent.>50% disseminate widely to distant sites such as bone, liver and brain.5-vear survival rate is about 60% - 70%.