Eman Tayae Elsayed is an Clinical & Research Fellow works in Department of Surgery, University College of Medicine, Egypt. Her academic interest are Hepatobiliary and pancreatic surgery / Surgical oncology for pancreatic cancer / Molecular Imaging by two-photon microscopy Pancreaticcancer,microenvironment / Cancer metabolism


Background: Peripheral blood mitochondrial DNA (mtDNA) copy number alteration has been suggested as a risk factor for several types of cancer. The aim of the present study was to assess the role of peripheral blood mtDNA copy number variation as a non-invasive biomarker in prediction and early detection of renal cell carcinoma in a cohort of Egyptian patients.
Methods: Quantitative real-time polymerase chain reaction (qPCR) was used to measure peripheral blood mtDNA copy number in 57 patients with newly diagnosed, early-stage localized renal cell carcinoma and 60 age- and sex- matched healthy individuals as a control group. 
Results: Median mtDNA copy number was significantly higher in renal cell carcinoma cases than in controls (166 versus 91, P<0.001). Increased mtDNA copy number was associated with 18-fold increased risk of RCC (95% confidence interval: 5.065-63.9). On using receiver operating characteristic curve analysis, it was found that mtDNA could distinguish between RCC patients and healthy controls with 86% sensitivity, 80% specificity, 80.3 % positive predictive value and 85.7% negative predictive value at cutoff value of 108.5. 
Conclusion:  This study suggests that increased peripheral blood mtDNA copy number could be used as a potential independent predictor of RCC risk. In addition, it may serve as a promising non-invasive biomarker for early detection of RCC.