Patient-Specific Dosimetry in Radioligand Therapy (RLT) for Metastatic Prostate Cancer Using 177Lu-DKFZ-PSMA-617
	    		
		   		
		   			 
		   		
	    	
    	 
    	10.1007/s13139-021-00713-7
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Elahe MAHMOUDI
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Elahe PIRAYESH
			        		
			        		;
		        		
		        		
		        		
			        		Mohammad Reza DEEVBAND
			        		
			        		;
		        		
		        		
		        		
			        		Mahasti AMOUI
			        		
			        		;
		        		
		        		
		        		
			        		Mehrdad GHORBANI RAD
			        		
			        		;
		        		
		        		
		        		
			        		Mahdi  GHORBANI
			        		
			        		
		        		
		        		
		        		
    Author Information Author Information
 
			        		
			        		
			        			1. Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
 
 
- Publication Type:ORIGINAL ARTICLE
- From:Nuclear Medicine and Molecular Imaging
	            		
	            		 2021;55(5):237-244
	            	
            	
- CountryRepublic of Korea
- Language:English
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		        	Abstract:
			       	
			       		
				        
				        	 Purpose:177Lu-DKFZ-PSMA-617 is a promising treatment for patients with metastatic prostate cancer. Specific dosimetry for each patient is an important factor in planning the patient’s treatment process. This study aimed to perform an image-based absorbed dose calculation for the treatment of metastatic prostate cancer with 177Lu-DKFZ-PSMA-617. 
				        	
 Methods:The individualized patient dosimetry calculations were based on whole-body planar scintigraphy images acquired in 10 patients with a mean age of 71.4 ± 6.07 years (range 63–85 years) at approximately 0–2 h, 4–6 h, 18–24 h, and 36–48 h after administration of the mean 6253 ± 826.4 MBq (range 5500–7400 MBq) of 177Lu-DKFZ-PSMA-617. Time-activity curves were generated for various organs. For count conversion to activities, calibration factors were calculated. Finally, the absorbed dose for an individual cycle was calculated using IDIAC-DOSE 2.1 software.
 Results:On average, the calculated absorbed dose for the kidneys and salivary glands were 0.46 ± 0.09 mGy/MBq and 0.62 ± 0.07 mGy/MBq, respectively.
 Conclusions:Based on the results, the 177 Lu-PSMA-617 therapy is a safe method for the treatment of castration-resistant prostate cancer patients. Large inter-individual variations in organ dose were found, demonstrating the need for patientspecific dosimetry and treatment planning.