Circulating DNA in Serum as a Tumor Marker in Precancerous Lesions of the Cervix in Mexican Women

Introduction: Cervical cancer is the fourth leading cause of death in the world. This poor prognosis is due to the fact that in two out of three cases the disease is diagnosed in advanced stages. Consequently, advances in detection methods can lead to early diagnosis of the disease and consequently to an improved prognosis. Methods based on serum-based tumor markers are a promising tool for early diagnosis and in general for biochemical screening of cancer patients. They also offer the added value of being non-invasive methods. Evidence has been found for the release of cellular DNA into the blood, so its quantification has the potential to serve as a tumor marker. If this DNA is detected in serum, it can reflect tumor size, viral load and response to treatment. Objective: To determine the amount of circulating DNA in serum of patients with precancerous lesions. Methods: The study was carried out with 40 healthy women and 120 women with precancerous lesions, who attended gynecological-obstetric care. Of the 120, 60 had low-grade lesions and 60 had high-grade lesions. All participants had a blood sample taken for determination of circulating DNA in serum. Specific oligonucleotides were used to determine not only the amount of circulating DNA in the patient, but also the amount of viral DNA. Papillomavirus detection/genotyping was performed by qPCR. One third of the patients showed at least one high-risk genotype. Conclusion: In this study, differential quantification of both patient and viral circulating DNA was observed.