This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Renal carcinoma, Subject name: Pathology
Which one of the following is not a feature of clear cell carcinoma of the kidney? 
Select and explain. 
A. Bony secondaries, B. Childhood tumour, C. Haematuria, D. Renal vein invasion
B: Childhood tumour
Answer: B: Childhood tumour 
Explanation: * Clear cell carcinoma arises from Proximal Convoluted Tubule * Most common ,associated with VHL gene mutation, invade the renal vein& bony secondaries. * Clinical features : -Hematuria -Palpable mass -Costoveebral pain -Fever/ weight loss/malaise * It is not a childhood tumor.