Biomarkers for Predicting Neoadjuvant Chemoradio-resistance for Middle-low Advanced Rectal Cancer

Study Overview
=================
Brief Summary
-----------------
Neoadjuvant therapy has been widely applied to locally advanced rectal cancer. However, about 50% of patients receiving this therapy do not respond well as evidenced by the fact that their T or N stages are not effectively decreased judged by postoperative pathological examination. The purpose of this trail is to identify the biomarkers (from within patients' tumor mass before neoadjuvant therapy) to predict resistance to neoadjuvant therapy. These biomarkers can help stratify neoadjuvant-resistant patients towards surgery while avoiding unnecessary chemoradio-based neoadjuvant therapy.

Detailed Description
-----------------
According to postoperative pathological examination results, all participants will be divided into two groups: complete response (ypT0N0) and poor response (>ypT1-2N0). Differentially expressed genes between complete response and poor response will be analyzed. A scoring formula will be established based on the results. Tumor tissue samples are collected before neoadjuvant therapy and will be analyzed via RNA sequencing.

Official Title
-----------------
Identification of Tissue Biomarkers for Predicting Neoadjuvant Chemoradio-resistance in Patients With Middle-low Local Advanced Rectal Cancer.

Conditions
-----------------
Rectal Cancer, Cancer of Rectum, Cancer of the Rectum, Neoplasms, Rectal, Rectal Tumors, Rectum Cancer, Rectum Neoplasms

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Histopathology proved to be adenocarcinoma of the rectum. The edge of tumor is within 12cm of anus margin. According to the eighth edition of AJCC TNM staging standard ,that staging for Ⅱ-Ⅲ period, as T3-T4, N0 or any T, N1-2. There is no history of chemotherapy, radiotherapy or immunotherapy before neoadjuvant therapy. Understand and agree to sign the informed consent for the study. Exclusion Criteria: With intestinal obstruction or impending obstruction, or perforation. With other malignancies occurred within 5 years.

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 |
| --- | --- |
| Complete response<br>After neoadjuvant therapy, postoperative pathological examination will be performed to evaluate the efficacy of the therapy. Define postoperative staging ypT0N0 as complete response. | |
| Poor response<br>After neoadjuvant therapy, postoperative pathological examination will be performed to evaluate the efficacy of the therapy. Define postoperative staging >ypT1-2N0 as poor response. | |

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparing gene expression differences between poor response group and complete response group by using RNA sequencing. | Using RNA-seq sequencing method to obtain the whole genome transcription profiles of the poor response group and complete response group, and compare the gene expression differences between these two groups. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival(OS) | The total survival time of the participants from joining the group to the death. If the death time is unknown, the relevant participants will be excluded for analysis. | 3 years | 
| Progression Free Survival(PFS) | The time period that from participants joining the groups to the progression of disease(recurrence or metastasis) or death of any cause. | 3 years |