Monitoring Efficacy of Radiotherapy in Lung Cancer and Esophageal Cancer

Monitoring Efficacy of Radiotherapy Based on Next Generation Sequencing Liquid Biopsy Technique in Lung Cancer and Esophageal Cancer: a Prospective Study

Lung cancer, one of the malignant tumors which poses a threat to human's health, has increased morbidity and mortality recently. Radiotherapy, as one of the common treatments, has important value in clinical application. Esophageal cancer, one of the most common digestive system cancers, has poor prognosis and high mortality. Esophageal cancer has high aggressive and many patients can't get surgical treatment because of the tumor metastasis at the time of diagnosis.Currently, chemoradiotherapy has become one of the standard treatment regimens for patients with unresectable esophageal cancer in National Comprehensive Cancer Network(NCCN). So radiotherapy is one of the most important treatments in esophageal cancer.

Currently, the efficacy evaluation method of radiotherapy is by imaging examination after several courses of treatment. However, new reports suggest that circulating tumor DNA(ctDNA) has the potential to be an indicator of therapeutic effectiveness and recurrence risk.

Circulating free DNA (cfDNA) can be found dissolved in plasma and serum, at variable amounts. In the case of cancer patients, ctDNA is a fraction of the cfDNA derived from tumor. Currently, the ctDNA is widely used in "liquid biopsy" for not only does it carry the same somatic alterations as the tumor itself but also its percentage is correlated with tumor burden.

This study will investigate the clinical value of efficacy evaluation and prognosis of ctDNA detecting technique in patients with radiotherapy.

Inclusion Criteria:

• Patients with histopathological proved lung cancer or esophageal cancer.
• Candidate for radiotherapy.
• No history of prior anti-tumor treatment.
• Eastern Cooperative Oncology Group (ECOG) score 0,1.
• Being able to receive computed tomography (CT) and magnetic resonance imaging (MRI).
• Blood sample is available for dynamic monitoring.
• Written informed consent provided.
• Good compliance in the follow-up.

Exclusion Criteria:

• Had received radiotherapy, chemotherapy, biotherapy or other treatment that is related to lung cancer or esophageal cancer.
• The patients have the sign of any serious or uncontrolled systematic diseases that may have significant impact on the balance between risk and benefit, such as hypertension, infection of hepatitis B, hepatitis C or human immunodeficiency virus(HIV).
• With history of alcohol or drug abuse.