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What is 13, years old boy, the LEAST common cause of proximal lytic lesion of the head of the femur is - and explain in detail?
If multiple myeloma occurs as a solitary lesion it is known as Plasmacytoma
Age gp is 6th-7th decade, Rare before 40yrs of age
So the lytic lesion in a 13 yrs old boy cannot be a plasmacytoma