Survival Rates and Quality of Life According to Follow-up Period After Gastrectomy for Gastric Cancer (STOFOLUP)

Study Overview
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Brief Summary
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This study is a multi-center, prospective, randomized controlled study. The aim of this study is to compare survival rates and to observe quality of life and nutritional status according to follow-up period in patients who underwent radical gastrectomy for stage 2 or 3 gastric cancer.

Detailed Description
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The hypothesis of this study is that the survival rates would be different between the 3 months and 6 months follow-up groups. The investigators expected survival differences of 6% and the anticipated 3-year overall survival is 83% in the 6 months follow-up group based on the previous 3 phase clinical trial. On the basis of this hypothesis, the sample size was calculated as 886 patients. Patients who were diagnosed as stage 2 or 3 gastric cancer after gastrectomy will be assigned to 3 months or 6 months follow-up group. The planned examinations including blood test, X-ray , CT, endoscopy, and nutritional markers will be performed according to the protocol and each patients will be followed up for 3 years after enrollment. The primary endpoint is 3 year overall survival and secondary endpoints are other survivals such as 3-year disease-free survival and gastric cancer specific survival, quality of life, and nutritional parameters.

Official Title
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A Prospective Multi-center Randomized Clinical Trial to Compare Survival Rates and Quality of Life According to Follow-up Period in Patients Who Underwent Radical Gastrectomy for Advanced Gastric Cancer (STOFOLUP Trial)

Conditions
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Gastric Cancer, Recurrence, Quality of Life

Intervention / Treatment
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* Diagnostic Test: Computed tomography, Chest X-ray, and blood test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 19 years or more Patients who are diagnosed with pathological stage II or III gastric adenocarcinoma according to the AJCC 8th edition Patients who can understand all information about the trial and decide for themselves whether to participate in this study Exclusion Criteria: Vulnerable patients such as pregnant and intellectual disability Patients who cannot undergo CT owing to poor kidney function or severe adverse effects Patients who are already in another study and cannot follow the schedule for this trial Patients who are diagnosed with a cancer other than gastric cancer within five years before the gastrectomy Patients being treated for a cancer other than gastric cancer

Ages Eligible for Study
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Minimum Age: 19 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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 3 months follow-up<br>Patients will be follow-up every 3 months after gastrectomy. | Diagnostic Test: Computed tomography, Chest X-ray, and blood test<br>* CT will be performed every 3 months after gastrectomy in the 3-months follow-up group. CT will be performed every 6 months after gastrectomy in the 6 months follow-up group.<br>|
| Active Comparator: 6 months follow-up<br>Patients will be follow-up every 6 months after gastrectomy. | Diagnostic Test: Computed tomography, Chest X-ray, and blood test<br>* CT will be performed every 3 months after gastrectomy in the 3-months follow-up group. CT will be performed every 6 months after gastrectomy in the 6 months follow-up group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 3-year overall survival | Death from any cause is defined as an event. | 3 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 3-year recurrence-free survival rate | Death from any cause and gastric cancer recurrence are an event. | 3 years after surgery | 
| 3-year gastric cancer specific survival rate | Death from gastric cancer is the only event. | 3 years after surgery | 
| 3-year post-recurrence survival rate | from recurrence detection date to last follow-up date (or death) | 3 years after surgery | 
| Summary score of KOQUSS-40 questionnaire | KOQUSS-40 consists of 8 domains with 40 questions for quality of life and post-gastrectomy symptoms. We will calculate the KOQUSS-40 summary score of each group and compare them between the two groups. The summary score is defined as the mean of eight symptom domains (Indigestion, dysphagia, reflux, dumping syndrome, bowel habit change, constipation, psychological factors, and worry about cancer). The minimum and maximum values are 0 and 100, and higher scores mean a better quality of life. | 3 years after surgery | 
| Summary score of EORTC QLQ C30 | EORTC QLQ C30 consists of 15 domains with 30 questions for quality of life of cancer patients. The 15 domains consist of five functional scales (physical, role, cognitive, emotional, and social functioning), a global QOL scale, three symptom scales (fatigue, nausea and vomiting, and pain), and six single items (appetite loss, diarrhea, dyspnea, constipation, insomnia, financial impact). We will calculate the EORTC QLQ C30 summary score of each group and compare them between the two groups. The summary score is defined as the mean of 13 domains (excluding global QOL scale and financial impact). The minimum and maximum values are 0 and 100, and higher scores mean a better quality of life. | 3 years after surgery | 
| Summary score of EORTC QLQ STO22 | EORTC QLQ STO22 consists of 9 domains with 22 questions for stomach cancer patients' symptoms. The 9 domains consist of five symptom scales (dysphagia, pain, reflux symptom, eating restriction, anxiety), four single items (having a dry mouth, taste, body image, and hair loss). We will calculate the EORTC QLQ STO22 summary score of each group and compare them between the two groups. The summary score is defined as the mean of 9 domains. The minimum and maximum values are 0 and 100, and higher scores mean a better quality of life. | 3 years after surgery | 
| Difference of body weight (kg) | Difference of body weight between preoperative and postoperative 3 year values | 3 years after surgery | 
| Incidence of iron deficiency anemia | Incidence of iron deficiency anemia for the 3 year follow-up after gastrectomy | 3 years after surgery | 
| Incidence of vitamin B12 deficiency | Incidence of vitamin B12 deficiency for the 3 year follow-up after gastrectomy | 3 years after surgery |