Comparison of Clinicopathological Characteristics Between Primary and Contralateral Cancers in BRCA1/2 Carriers with Metachronous Bilateral Breast Cancers
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3971/j.issn.1000-8578.2023.23.0211
   		
        
        	
        		- VernacularTitle:BRCA1/2突变异时性双乳癌首发癌和对侧癌的临床病理特征对比研究
 
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Xinyun DING
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Jie SUN
			        		
			        		;
		        		
		        		
		        		
			        		Jiuan CHEN
			        		
			        		;
		        		
		        		
		        		
			        		Lu YAO
			        		
			        		;
		        		
		        		
		        		
			        		Ye XU
			        		
			        		;
		        		
		        		
		        		
			        		Yuntao XIE
			        		
			        		;
		        		
		        		
		        		
			        		Juan ZHANG
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. Familial & Hereditary Cancer Center, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing 100142, China
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Research Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		BRCA status;
			        		
			        		
			        		
				        		Metachronous bilateral breast cancer;
			        		
			        		
			        		
				        		Molecular subtype;
			        		
			        		
			        		
				        		Triple-negative breast cancer
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Cancer Research on Prevention and Treatment
	            		
	            		 2023;50(7):652-657
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Objective To compare the clinicopathological characteristics between primary and contralateral cancers in patients with metachronous bilateral breast cancer (MBBC) who carried a BRCA1/2 germline pathogenic variant. Methods A total of 496 BRCA1/2 carriers with primary unilateral breast cancer were included (196 with BRCA1 and 300 with BRCA2). Clinicopathological information of patients was collected, and the median follow-up for the entire cohort was 10.4 years (0.4-20.8 years). Results Among all patients, 31 (15.8%) of the 196 BRCA1 carriers and 49 (16.3%) of the 300 BRCA2 carriers had MBBC, respectively. Among the 31 BRCA1 carriers who developed MBBC, the proportion of triple-negative breast cancer (TNBC) in primary cancer and contralateral cancer was 61.3% and 67.7%, respectively. If the primary cancer of BRCA1-mutated MBBC was TNBC, the probability of the contralateral breast cancer with TNBC was 89.5% (17/19), which was significantly higher than that if the primary cancer was non-TNBC (33.3%, 4/12) (P=0.004). Among the 49 BRCA2 carriers who developed MBBC, the predominant molecular phenotype of the primary and contralateral cancers was HR+ & HER2- (77.6% and 67.3%, respectively; P=0.53). Conclusion Approximately 60% of BRCA1 carriers exhibit TNBC. If a BRCA1 carrier with a TNBC primary breast cancer had an MBBC, the probability of the contralateral breast cancer being TNBC phenotype is almost 89.5%.