HISTORY:
                   A male in his 50s presents with gross hematuria and flank pain. Computed tomography (CT) of abdomen and pelvis showed a 7 cm lobulated mass in right kidney.
                     
                    
                 
                 
						
                         
			             
                       
			             
			             
                       
			            
			        	      	
                           AE1/AE3, WT-2, CAIX, CD3, CD20, CD45, CK7 and CK20 stains were also done and read as negative.
			               
                       
               
                      
                       
                
                    
                 
                            What is the most likely diagnosis?
                            
                               - Nephroblastoma
 
                               - Primary Ewing sarcoma of the kidney
 
                               - Desmoplastic small round cell tumor of kidney
 
                               - Lymphoma
 
                               - Small cell carcinoma of the kidney
 
                            
                          
                       
                         
                        
                         
                            
                         
                           Primary Ewing sarcoma of the kidney