Initial Treatment Approach for Signet Ring Cell Gastric Adenocarcinoma

Treatment Strategy Based on Stage

The American College of Surgeons recommends surgery alone with D2 lymphadenectomy as the initial treatment for localized signet ring cell gastric adenocarcinoma, as perioperative chemotherapy provides no survival benefit and is associated with worse outcomes in this histologic subtype 1
For pT1apN0 tumors after complete R0 resection, observation without additional adjuvant treatment is recommended by the National Comprehensive Cancer Network 2
Endoscopic submucosal dissection (ESD) is NOT recommended for signet ring cell carcinoma because these lesions are multifocal and occur throughout the stomach, making endoscopic or limited resection inappropriate, as stated by the Gut journal 3, 1

Complete R0 resection with D2 lymphadenectomy is essential, as negative margins are a critical prognostic factor, according to the Praxis Medical Insights 2
Subtotal gastrectomy is appropriate for distal tumors, while total gastrectomy is required for proximal lesions, as recommended by the National Comprehensive Cancer Network 4

For patients with CDH1 germline pathogenic variants, prophylactic total gastrectomy between ages 20-30 years is the only effective prevention strategy, as stated by the Praxis Medical Insights 1
D1 lymphadenectomy is recommended as a pragmatic compromise for prophylactic procedures by the Praxis Medical Insights 1
Baseline endoscopy is mandatory before prophylactic surgery to exclude established cancer requiring neoadjuvant treatment, according to the Praxis Medical Insights 1

For unresectable or metastatic disease, systemic chemotherapy based on fluoropyrimidine-platinum combinations is recommended, though response rates are poor in signet ring cell histology, as stated by the National Comprehensive Cancer Network and Annals of Oncology 5, 6, 7
HER2 testing should be performed, as trastuzumab plus chemotherapy is indicated for HER2-positive disease, according to the National Comprehensive Cancer Network and Cancer Communications 5, 7
Best supportive care alone is appropriate for patients with poor performance status, as recommended by the National Comprehensive Cancer Network 4

Do not attempt endoscopic resection even for small lesions, as multifocal disease is characteristic, as stated by the Gut journal and Praxis Medical Insights 3, 1

A minimum of 14 lymph nodes, optimally at least 25, should be examined pathologically for accurate staging, according to the European Society for Medical Oncology guidelines 8, 9
Laparoscopy with or without peritoneal washings should be performed preoperatively in all potentially resectable cases to exclude occult peritoneal metastases, as recommended by the European Society for Medical Oncology 8, 9

For unresectable or metastatic signet ring cell carcinoma, systemic chemotherapy is recommended, with options including fluoropyrimidine-platinum combinations, although response rates remain poor in this histology, as noted by the European Society for Medical Oncology 10, 11
Palliative chemotherapy should only be offered to patients with adequate performance status, according to the European Society for Medical Oncology guidelines 10, 11

Do not proceed to surgery without staging laparoscopy in potentially resectable cases, as imaging frequently misses peritoneal metastases that would change management, as recommended by the European Society for Medical Oncology 8, 9
Do not accept inadequate lymph node evaluation (fewer than 14 nodes examined), as this leads to understaging and suboptimal treatment planning, according to the European Society for Medical Oncology guidelines 8, 9