ctDNA-based MRD Assessment in Local Advanced Esophageal Carcinoma

Study Overview
=================
Brief Summary
-----------------
To analyze the relationship between the dynamic changes of circulating tumor DNA (ctDNA) and tumor relapse of esophageal squamous cell carcinoma treated by concurrent chemoradiotherapy.

Official Title
-----------------
Circulating Tumor DNA-based Minimal Residual Disease (MRD) Assessment in Local Advanced Esophageal Squamous Cell Carcinoma Treated by Definitive Concurrent Chemoradiotherapy

Conditions
-----------------
Esophageal Squamous Cell Carcinoma

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: 18-75 years old. ECOG 0-1. Esophageal squamous cell carcinoma confirmed by pathology. No radiotherapy, chemotherapy, or other treatments prior to enrollment. Locally advanced esophageal squamous cell carcinoma (II-IVa, IVB with supraclavicular lymph node metastasis). No severe abnormal hematopoietic, cardiac, pulmonary, renal, hepatic function, or immunodeficiency. Informed consent signed. Exclusion Criteria: Less than 50.4Gy/28fx of radiotherapy dose. Without Concurrent chemotherapy. Pregnant or breastfeeding women or fertile patients who refused to use contraceptives.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ctDNA(+) Cohort<br>ctDNA(+) Cohort in pretreatment and posttreatment plasma samples was defined by accessing the presence of one or more mutations identified in match tumor samples. | |
| ctDNA(-) Cohort<br>ctDNA(-) Cohort in pretreatment and posttreatment plasma samples was defined by the absence of one or more mutations identified in match tumor samples. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between ctDNA status after chemoradiotherapy and relapse. | To assess if recurrent esophageal cancer is detectable earlier by ctDNA positive in plasma. | ctDNA will be tested within 1 year after chemoradiotherapy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of ctDNA status. | To dynamically evaluate the ctDNA status at baseline, during treatment and follow-up. | before and at the end of radiotherapy (+1 week); at the end of consolidation chemotherapy (+1 week); at 2 weeks, 1 month, 3 months, 6 months, 9 months, 1 year after dCCRT. | 
| Overall survival (OS). | To compare OS in ctDNA(+) patients and ctDNA(-) patients. | through study completion, an average of 2 years. | 
| Relapse-free survival (RFS) and progression-free survival (PFS). | To compare RFS and PFS in ctDNA(+) patients and ctDNA(-) patients. | through study completion, an average of 2 years. | 
| Relationships between radiomics features, ctDNA status and relapse. | To assess if recurrent esophageal cancer is detectable earlier by ctDNA positive in plasma compared to traditional radiographic methods. | through study completion, an average of 2 years. |