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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.
user
The diagnosis of a patient presenting with familial Polyostosis, Precocious puberty and Pigmentation is
assistant
The correct answer is  McCune Albright syndrome :

A polyostotic form of fibrous dysplasia
Cutaneous pigmentation
Endocrine dysfunction, especially Precocious puberty in girls.
The triad of symptoms in the question thus characterizes McCune Albright syndrome and hence is the answer.