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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Zellballen pattern on histopathology is observed in?-
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The correct answer is  Zellballen pattern on histopathology is observed in Paraganglioma or Carotid body tumors. Zellenbalen- composed to nests of polygonal chief cells. Robbins basic pathology. 7th edition. page no. 789.