The principle of comprehensive treatment should be adopted, that is, according to the pathological type and clinical stage of tumor, combined with the general condition and functional status of patients, multidisciplinary team (MDT) model should be adopted to apply surgery, chemotherapy, radiotherapy and biologic targeting in a planned and rational way to achieve radical or maximum control of tumor, prolong patients’ survival and improve their quality of life. The aim is to achieve radical or substantial tumor control, prolong patient’s survival and improve life quality.
1.For early stage gastric cancer without evidence of lymph node metastasis, endoscopic treatment or surgery can be considered according to the depth of tumor invasion, without adjuvant radiotherapy or chemotherapy after surgery.
2. Early gastric cancer with localized progressive stage or lymph node metastasis should be treated with comprehensive treatment mainly by surgery. Depending on the depth of tumor invasion and whether it is accompanied by lymph node metastasis, direct radical surgery or preoperative neoadjuvant chemotherapy can be considered before radical surgery. Adjuvant treatment plan (adjuvant chemotherapy and, if necessary, adjuvant chemoradiotherapy) should be decided according to the postoperative pathological stage for locally progressive gastric cancer that has been successfully performed radical surgery.
3. Recurrent/metastatic gastric cancer should be treated with a comprehensive treatment based on drug therapy, and local treatment such as palliative surgery, radiotherapy, interventional therapy, radiofrequency therapy should be given at the appropriate time, and the best supportive treatment such as pain relief, stent placement and nutritional support should also be actively given.
Surgical resection is the main treatment for gastric cancer and the only way to cure it. Gastric cancer surgery is divided into radical surgery and palliative surgery, and radical resection should be strived for. Radical surgery for gastric cancer includes EMR, ESD, D0 resection and D1 resection for early gastric cancer, and (D2) and expanded surgery (D2+) for partially progressive gastric cancer. Palliative surgery for gastric cancer includes palliative resection for gastric cancer, gastrojejunostomy, jejunal nutrition tube placement, etc.
Surgical procedures should be performed to completely remove the primary lesion and thoroughly clear the regional lymph nodes. For gastric cancer with limited growth, the margin should be at least 3 cm from the lesion; for gastric cancer with infiltrative growth, the margin should be more than 5 cm from the lesion; for gastric cancer adjacent to esophagus and duodenum, the lesion should be removed as completely as possible, and intraoperative frozen pathological examination should be performed if necessary to ensure that no cancer remains in the margin. Nowadays, D (dissection) is still used to indicate the range of lymph node clearance, such as D1 surgery refers to clearing regional lymph nodes to station 1, D2 surgery refers to clearing regional lymph nodes to station 2, and if the requirement of lymph node clearance at station 1 is not met, it is regarded as D0 surgery.
Laparoscopy is a recently developed minimally invasive surgical technique, and its application in gastric cancer should be suitable for stage I patients at present.
2.Operative style and indications.
(1) Reduction surgery.
The scope of resection is smaller than that of standard radical surgery.
(1) Endoscopic mucosa resection (EMR) and endoscopic submucosa dissection (ESD) indications: highly or moderately differentiated, non-ulcerated, less than 2 cm in diameter, no lymph node metastasis intra-mucosal cancer.
Gastric D1 resection indications: intramucosal carcinoma with a diameter of more than 2 cm, and gastric carcinoma invading the submucosa. Once lymph node metastasis appears, D2 resection should be performed.
(2) Standard surgery.
D2 radical surgery is the standard surgery for gastric cancer. If the depth of tumor infiltration exceeds the submucosa layer (muscle layer or above), or if there is lymph node metastasis but it has not yet invaded the adjacent organs, the standard surgery (D2 radical surgery) should be performed.
(3) Standard surgery + combined visceral resection: if the tumor infiltrates the adjacent organs.
(4) Palliative surgery: Only for those with distant metastasis or tumor invading important organs that cannot be removed and combined with bleeding, perforation, obstruction, etc. The purpose of palliative surgery is to relieve the symptoms and improve the quality of life.
3. Contraindications to radical surgery.
(1) Systemic conditions that cannot tolerate surgery.
(2) Local infiltration is too extensive for complete resection.
(3) Definite evidence of distant metastasis, including distant lymph node metastasis, extensive peritoneal dissemination, more than 3 metastases in the liver, etc.
(4) The presence of significant defects in the function of the heart, lungs, liver, kidneys and other important organs, severe hypoproteinemia, anemia, malnutrition and other conditions that cannot tolerate surgery.