Genomic Study of Relapse Esophageal Cancer After Radiotherapy

Study Overview
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Brief Summary
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Radiotherapy plays an important role in multidisciplinary treatment of esophageal cancer. However, about half patients received radiotherapy occurred relapse. Once relapse occurred, there is no better treatment strategy. Genomic study of relapsed esophageal cancer is seldom. So the investigators attempt to collect relapsed tissue to conduct with whole exome sequencing in order to investigate the genome landscape of recurrence esophageal cancer.

Detailed Description
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Tumor tissue of patients received radiotherapy with diagnosis of recurrence between Jan 1, 2010 and Dec 1, 2020 were collected retrospectively. Recurrence tumor tissue is collected between Dec 31, 2020 and Dec 31, 2022 prospectively. Blood and preradiotherapy tumor tissue were also collected to be as contrast. A total of 100 paired blood, preradiotherapy tumor tissue and relapse tumor tissue were collected. What is more, a total of 100 paired blood and preradiotherapy tumor tissue with diagnosis of no recurrence were collected. All samples were conducted with whole exome sequencing. Here the investigators define recurrence period as within 2 years and no recurrence period as more than 3 years after radiotherapy. Criteria of relapse: (1) pathologic diagnosis is squamous carcinoma before radiotherapy;(2) received radiotherapy; (3)pathologic diagnosis is also squamous carcinoma after radiotherapy; (4) clinical symptoms including feeding obstruction etc; (5) imaging evidence showed disease progression.

Official Title
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Genomic Study of Relapse Esophageal Cancer After Radiotherapy

Conditions
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Gene Mutation-Related Cancer, Esophageal Cancer, Radiation Exposure

Intervention / Treatment
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* Genetic: whole exome sequence


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: pathologic diagnosis is squamous cell carcinoma before radiotherapy; pathologic diagnosis is squamous cell carcinoma after radiotherapy; received radiotherapy clinical symptoms including dysphagia, feeding obstruction, etc image evidence showed disease progression the period of recurrence was within 2 years after radiotherapy Exclusion Criteria: pathologic diagnosis is not squamous cell carcinoma before radiotherapy; pathologic diagnosis is not squamous cell carcinoma after radiotherapy not received radiotherapy the period of recurrence was more than 2 years after radiotherapy the period of no recurrence was within 3 years after radiotherapy
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 |
| --- | --- |
| Recurrence<br>The period of recurrence was within 2 years after radiotherapy. Pathologic diagnosis was squamous cell carcinoma same with preradiotherapy. | Genetic: whole exome sequence<br>* To seek genomic characteristics of relapsed esophageal cancer with whole exome sequence.<br>|
| No recurrence<br>The period was more than 3 years after radiotherapy and no recurrence signs were observed. | Genetic: whole exome sequence<br>* To seek genomic characteristics of relapsed esophageal cancer with whole exome sequence.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| genomic characteristics of relapsed esophageal cancer | gene mutations, copy number variants | through study completion, an average of 1 year |