Cell-free circulating DNA: Diagnostic value in patients with renal cell cancer.
OBJECTIVE
To analyse the diagnostic and prognostic value of cell-free DNA in patients with renal cell carcinoma (RCC).


METHODS
Cell-free DNA was measured in 35 patients with RCC and 54 healthy individuals using quantitative real-time PCR. ACTB-106 detects fragmented cell-free DNA due to apoptosis and ACTB-384 detects long DNA fragments by necrosis. DNA-Integrity (ACTB-384/ACTB-106 ratio) served as measure of DNA fragmentation.


RESULTS
Levels of both DNA fragments were increased in RCC patients compared to healthy individuals (ACTB-384: 1.77 vs. 0.61ng/ml, p=0.0003; ACTB-106: 1.31ng/ml vs. 0.77 ng/ml p=0.003). Receiver operator characteristic analysis (ROC) showed at a threshold level of 1.03 ng/ml for ACTB-106 68.6%, sensitivity and 70.4% specificity (AUC: 0.69). ROC analysis showed at a threshold level of 1.70 ng/ml for ACTB-384 57.1%, sensitivity and 81.5% specificity (AUC: 0.73). DNA integrity was increased in RCC (1.07 vs. 0.72 p=0.04). In vascular invasion the DNA integrity was reduced (p=0.003).


CONCLUSIONS
Cell-free-DNA levels are increased in RCC. The DNA integrity indicates mostly necrotic origin in RCC.
Hauser
Stefan
S
Department of Urology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany. Stefan.Hauser@uni-bonn.de
Zahalka
Tobias
T
Ellinger
Jörg
J
Fechner
Guido
G
Heukamp
Lukas C
LC
VON Ruecker
Alexander
A
Müller
Stefan C
SC
Bastian
Patrick J
PJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D002292:Carcinoma, Renal Cell / Q000097:blood* / Q000235:genetics*; D016022:Case-Control Studies; D053938:DNA Fragmentation; D004273:DNA, Neoplasm / Q000097:blood*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000097:blood* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm