460P - The role of fluorescence-based cell-free DNA assay for detection of cancer by comparing patients with and without cancer

Background

A fluorescence-based cell-free DNA (CFD) assay is a simple method for measuring nucleic acids without prior DNA extraction and amplification. Despite numerous studies on CFD, there were few studies that compare the amount of CFD using fluorescence assay between cancer patients and healthy subjects. We investigated whether the amount of CFD is different between cancer patients and participants without any evidence of malignancy.

Methods

We collected blood samples from patients who were diagnosed as any kind of cancer with distant metastasis (patients’ group), and from participants who have completed cancer treatment and were confirmed to have no malignancy at least for 1 year (NED group). Plasma CFD level were analyzed using PicoGreen^TM reagent in each group.

Results

Totally 134 participants [patients’ group (n=72), NED group (n=52)] were enrolled. Median age was 69 (27–83) in patient’s group and 65 (34–81) in NED group. In patients’ group, most common primary origin was biliary tract (18, 25.0%), urothelial origin (15, 20.8%), pancreas (13, 18.1%), stomach (5, 6.9%), and prostate (5, 6.9%). Median CFD in the patients’ group (9.80 ± 2.20 μg/mL) were significantly higher than that of NED group (8.40 ± 0.86, p<0.001). In patients with high tumor burden indicating 3 or more of metastatic organs, CFD was significantly higher (10.70 ± 3.26) than that in patients with low tumor burden (9.45 ± 1.47, p=0.008). There was no significant correlation between CFD and tumor markers including carcinoembryonic antigen (p=0.468) and carbohydrate antigen 19-9 (p=0.134). Other factors including body weight, body surface area, and age were not related with CFD (p>0.05).

Conclusions

In our study CFD was higher in cancer patients compared with NED, especially with higher tumor burden. Additionally, CFD was not correlated with other tumor markers. A fluorescence-based CFD assay needs further investigation as a versatile tool of cancer treatment including early detection, monitoring for treatment responses, and predicting prognosis based on our results.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.