Detection of Plasma Circulating Tumor DNA in Gastric Cancer

Study Overview
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Brief Summary
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The aim of this study is to develop a protocol for detection of circulating tumor DNA (ctDNA) in plasma of patients with early stages of gastric cancer.

Detailed Description
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Gastric cancer (GC) is the fifth most common cancer worldwide and the third leading cause of cancer deaths. Earlier detection of GC can dramatically increases the five-year survival rate up to > 90%. The current endoscopy and tissue biopsy remain excessively expensive for middle-income nations, in addition to being fairly invasive, with possible complications. Additionally, most of serum-based biomarkers such as carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 72-4 (CA72-4), and carbohydrate antigen 125 (CA125) are not recommended for detection of GC due to the limit of specificity and sensitivity in the early stages of GC. Thus, it is essential to identify new biomarkers for diagnosis of early stages of GC. In this study, the investigators develop an ultradeep massive parallel sequencing (MPS) assay to detect tumor derived mutations (TDM) in plasma of early stages of GC. This study provides proof-of-principle for eventual clinical employment of circulating DNA, via liquid biopsy, for detection of early stages of GC.

Official Title
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Detection of Plasma Circulating Tumor DNA in Gastric Cancer

Conditions
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Circulating Tumor DNA (ctDNA), Gastric Cancer

Intervention / Treatment
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* Diagnostic Test: plasma circulating tumor DNA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or Female patients aged 18 years and older Histologically proven stage (I, II and IIIA) gastric adenocarcinoma Naivety to treatment. No known other concomitant cancer diagnosis Signed informed consent Exclusion Criteria: Pathologically late stage (stage IIIB and IV) or metastatic gastric adenocarcinoma Underwent any type of treatment Unable to undergo biopsy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 100 healthy people<br>10 ml blood and tissue biopsy were collected from each patient | Diagnostic Test: plasma circulating tumor DNA<br>* A liquid biopsy assay for identification of tumor derived mutations in plasma of gastric cancer<br>|
| 100 gastric cancer patients<br>10 ml blood and tissue biopsy were collected from each patient | Diagnostic Test: plasma circulating tumor DNA<br>* A liquid biopsy assay for identification of tumor derived mutations in plasma of gastric cancer<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The sensitivity and and specificity of our mutation-based assay for detecting early-stage gastric cancer patients | sensitivity and and specificity of our mutation-based assay for detecting early-stage gastric cancer patients | 1 months after collecting blood and specimen | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Limit of detection (LOD): the lowest variant allelic frequency that can be reliably detected | the lowest variant allelic frequency that can be reliably detected | 1 months after collecting blood and specimen | 
| The concordance rate of mutation results between plasma and tissue biopsy assay | The concordance rate of mutation results between plasma and tissue biopsy | 1 months after collecting blood and specimen |