Safety of Laparoscopic Resection for Gastrointestinal Stromal Tumor on Unfavorable Anatomic Site of Stomach：a Multicenter Prospective Trial（CLASS-06）
Phase: NA
Conditions: Gastrointestinal Stromal Tumors
Sponsor: RenJi Hospital

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Safety of Laparoscopic Resection for Gastrointestinal Stromal Tumor on 
Unfavorable Anatomic Site of Stomach：a multicenter prospective trial
（CLASS-06） 
 
Study Protocol 
Applying party：Renji Hospital affiliated to Shanghai Jiaotong University 
School of Medicine 
Principal Investigator（PI）： 
Cao Hui, M.D., Ph.D., F.A.C.S.  
Department of Gastrointestinal Surgery, Renji Hospital, School of Medicine, Shanghai 
Jiaotong University, Shanghai, China   
Cooperative Investigator (CI) 
Wang Ming 
Department of Gastrointestinal Surgery, Renji Hospital, School of Medicine, Shanghai 
Jiaotong University, Shanghai, China 
Li Guo-Xin, Yu Jiang 
Department of General Surgery, Nanfang Hospital, Southern Medical University, 
Guangzhou, Guangdong, China 
Su Xiang-Qian, Li Zi-Yu 
Department of Gastrointestinal Surgery, Peking University Cancer Hospital, Beijing, 
China 
Sun Yi-Hong 
Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, China 
Xu Ze-Kuan 
Department of General Surgery, The First Affiliated Hospital of Nanjing Medical 
University, Nanjing, Jiangsu, China 
Huang Chang-Ming, Zheng Chao-Hui 
Department of Gastric Surgery, Fujian Medical University Union Hospital, Fuzhou, 
Fujian, China 
Jiang Ke-Wei, Gao Zhi-Dong 
Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 
China 
Hu Wei-Guo, Zang Lu 
Department of General Surgery, Ruijin Hospital affiliated to Shanghai Jiao Tong 
University School of Medicine, Shanghai, China 
Tao Kai-Xiong 
Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, 
Huazhong University of Science and Technology, Wuhan, Hubei, China 
Hu Jian-Kun, Yang Kun 
Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, 
Chengdu, Sichuan, China 
Song Wu, Zhang Xin-Hua 

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Department of Gastrointestinal Surgery, The First Affiliated Hospital, Sun Yat-Sen 
University, Guangzhou, Guangdong, China 
Zheng Zhi-Chao 
Department of Gastric Surgery, Liaoning Cancer Hospital and Institute, Shenyang, 
Liaoning, China 
Du Xiao-Hui, Wu Xin 
Department of General Surgery, Chinese PLA General Hospital, Beijing, China 
 
V1.6 
2021.07.01 
 

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Agree to comply with SOP in the study 
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Confidentiality Statement: 
The information contained in this clinical protocol is only available to the investigators, the 
Ethics Committee and relevant agencies for review. Without approval from the principal 
investigator (PI), no information shall be given to a third party irrelevant to this study. 

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Abstract 
Protocol Titile 
Safety of Laparoscopic Resection for Gastrointestinal Stromal Tumor on 
Unfavorable Anatomic Site of Stomach：a multicenter prospective trial 
Protocol 
Version 
V1.6 
PI 
Cao Hui 
Research 
Centers 
Renji Hospital affiliated to Shanghai Jiaotong University School of Medicine 
Nanfang Hospital, Southern Medical University 
Peking University Cancer Hospital 
Zhongshan Hospital, Fudan University 
The First Affiliated Hospital of Nanjing Medical University 
Fujian Medical University Union Hospital 
Peking University People's Hospital 
Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine 
Union Hospital, Tongji Medical College, Huazhong University of Science and 
Technology 
West China Hospital, Sichuan University 
The First Affiliated Hospital, Sun Yat-Sen University 
Liaoning Cancer Hospital and Institute 
Chinese PLA General Hospital 
Indications 
Patients with gastrointestinal stromal tumor (GIST) at stomach whose 
diameter is ≥2cm and ≤5cm at unfavorable anatomic sites.  
Note: Favorable anatomic sites are defined as greater curvature and anterior 
wall of stomach by Soft Tissue Sarcoma, NCCN Clinical Practice Guidelines 
in Oncology (version 2. 2020). Accordingly, the unfavorable anatomic sites 
are defined as all the anatomic locations of stomach except greater curvature 
and anterior wall, including less curvature, posterior wall, and area near 
pylorus or cardia. 
Research 
Purpose 
The aim of this trial is to evaluate the safety of laparscopic resection for GIST 
whose diameter is ≥2cm and ≤5cm at unfavorable anatomic sites of stomach 

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Rsearch 
Design 
Prospective, multicenter, open-label, single-arm 
Case 
Grouping 
Study group: laparoscopic resection for GIST at unfavorable anatomic sites 
of stomach 
Determination
of Sample 
Size 
The reference group proportion is 0.9800 according to the 3-year disease free 
survival rate reported in the previous literature on the subject of gastric GIST 
with maxium diameter between 2 to 5cm. -0.06 is set to detect a non-
inferiority margin. The test statistic used is the one-sided Z test (unpooled). 
The significance level of the test is 0.025. The target Power is 0.80. The 
inconsistency rate between preoperative and postoperative pathological 
diagnosis of GIST from literature is about 30%The dropout rate during 
follow-up is assumed to be 10%.  The sample size needed by the study group 
was 182. 
Number of 
Research 
Centers 
 13 
Inclusion 
Criteria 
Diagnosed as gastrointestinal stromal tumor at unfavorable anatomic 
sites of stomach preoperatively by endoscopy, ultrasound endoscopy, CT 
or MRI; 
Diameter of tumor size is ≥2cm and ≤5cm confirmed by contrast CT or 
MRI; 
Patients whose tumor is resectable by laparoscopic techniques at 
preoperative assessment; 
No evidence of distant metastasis and tumor invading nearby organs at 
preoperative assessment; 
   Performance status of 0 or 1 on ECOG (Eastern Cooperative Oncology 
Group) scale;  
ASA (American Society of Anesthesiology) score I, Ⅱ, or III;  
Written informed consent. 

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Exclusion 
Criteria 
Women during pregnancy or breast-feeding;  
Severe mental disorder;  
History of previous upper abdominal surgery (except laparoscopic 
cholecystectomy);  
History of other malignant disease within the past five years;  
History of previous neoadjuvant imatinib therapy;  
History of unstable angina or myocardial infarction within the past six 
months  
History of cerebrovascular accident within the past six months;  
History of continuous systematic administration of corticosteroids within 
the past month;  
Requirement of simultaneous surgery for other disease;  
Emergency surgery due to complication (bleeding, obstruction or 
perforation);  
FEV1＜50% of predicted value.  
Patients with GIST locates at favorable anatomic sites detected by 
contrast CT, MRI or ultrasound endoscopy at preoperative assessment; 
Patients with GIST diameter ＜2cm or>5cm detected by contrast CT or 
MRI; 
Presence of distant metastasis or tumor invading nearby organs at 
preoperative assessment 
Withdrawal 
Criteria 
Patients postoperatively confirmed as non-GIST case by pathology; 
 
GIST Patients diagnosed with GIST at unfavorable anatomic site 
preoperatively but confirmed at favorable anatomic site intraoperatively; 
Patients confirmed as spontaneous tumor rupture, metastasis or invading 
nearby organs intraoperately;  
 
Requirement of simultaneous surgery for other disease; 
Sudden severe complications during the perioperative period (intolerable 

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surgery or anesthesia), which renders it unsuitable or unfeasible to 
implement the study treatment protocol as scheduled;  
Patients confirmed to require emergency surgery by attending physicians 
due to changes in the patient’s condition after enrolled into this study;  
Patients who voluntarily quit or discontinue treatment for personal 
reasons at any stage after enrolled in this study;  
Treatment implemented is proven to violate study protocol.  
Intervention 
Laparoscopic resection for GIST at unfavorable anatomic site of stomach will 
be conducted 
Endpoints 
Primary Endpoint: 
3-year disease-free survival rate (DFS) 
Second Endpoints: 
  Success rate of laparoscopic surgery 
Rate of intraoperative complication 
Rate of Postoperative complication 
3-year overall survival rate (OS) 
Postoperative recovery course 
Stastical 
considerations 
Statistical software SAS (version 9.4) will be used for statistical analysis. 
The efficacy will be tested for non-inferiority with historical comparison and 
the safety indicators adopts descriptive analysis.All statistical tests will be 
conducted by bilateral test. The test level with statistical significance is 0.05. 
The interval estimation of parameters is 95% confidence interval. K-M 
survival analysis and Cox regression model will be used for analysis of 
survival time data. Central effect analysis: mixed-effect model for 
quantitative measures, CMH method for qualitative measures, and 
hierarchical logistic regression model for grade variables, survival time 
variables will be evaluated and adjusted using a Cox regression model. The 
central effect analysis and subgroup analysis will be carried out according to 
the specific situation. Interim analysis of this study will be carried out. 

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