Myelofibrotic and leukemic transformation in 2016 WHO-defined Philadelphia-negative myeloproliferative neoplasm
	    		
		   		
		   			
		   		
	    	
    	- Author:
	        		
		        		
		        		
			        		Ik-Chan SONG
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Sang Hoon YEON
			        		
			        		;
		        		
		        		
		        		
			        		Myung-Won LEE
			        		
			        		;
		        		
		        		
		        		
			        		Hyewon RYU
			        		
			        		;
		        		
		        		
		        		
			        		Hyo-Jin LEE
			        		
			        		;
		        		
		        		
		        		
			        		Hwan-Jung YUN
			        		
			        		;
		        		
		        		
		        		
			        		Seon Young KIM
			        		
			        		;
		        		
		        		
		        		
			        		Deog-Yeon JO
			        		
			        		
		        		
		        		
		        		
			        		
			        		Author Information
			        		
 - Publication Type:ORIGINAL ARTICLE
 - From:Blood Research 2022;57(1):59-68
 - CountryRepublic of Korea
 - Language:English
 - 
		        	Abstract:
			       	
			       		
				        
				        	 Background:Information on myelofibrotic and leukemic transformations in Korean Philadelphia chromosome-negative myeloproliferative neoplasms (Ph ‒ MPNs) is limited. 
				        	
Methods:This study retrospectively analyzed transformations in patients diagnosed with essential thrombocythemia (ET), polycythemia vera (PV) prefibrotic/early primary myelofibrosis (pre-PMF), or overt primary myelofibrosis (PMF) based on the 2016 World Health Organization criteria between January 1996 and December 2020 at Chungam National University Hospital, Daejeon, Korea.
Results:A total of 351 patients (144 with ET, 131 with PV, 45 with pre-PMF, and 31 with PMF;204 men and 147 women) with a median age of 64 years (range, 15‒91 years) were followed for a median of 4.6 years (range, 0.2‒24.8 years). The 10-year incidence of overt myelofibrosis was higher in pre-PMF than in ET (31.3% and 13.7%, respectively; P =0.031) and PV (12.2%; P =0.003). The 10-year incidence of leukemic transformation was significantly higher in PMF than in ET (40.0% and 7.9%, respectively; P =0.046), pre-PMF (4.7%; P =0.048), and PV (3.2%; P =0.031). The 5-year incidence of leukemic transformation was higher in patients with secondary myelofibrosis (SMF) than in those with PMF (19.0% and 11.4%, respectively; P =0.040). The 5-year overall survival of patients with SMF was significantly worse than that of patients with pre-PMF (74% and 93%, respectively; P =0.027) but did not differ from that of patients with PMF (57%; P =0.744).
Conclusion:The rates and clinical courses of myelofibrotic and leukemic transformations in Korean patients with Ph ‒ MPN did not differ from those in Western populations. 
            