Multidisciplinary diagnosis and treatment of undifferentiated gastric cancer with a specific morphology: a case report

BACKGROUND: Due to ongoing research on digestive endoscopy, early gastric cancer has become a popular topic. Based on macro-research on morphology using the Paris endoscopic classification system and micro-explorations of histopathology under endoscopy, several researchers have organically combined endoscopy with pathology and surgery. This multidisciplinary combination of digestive endoscopy could improve the diagnosis rate and cure rate of early gastric cancer. CASE DESCRIPTION: A 45-year-old female patient underwent gastroscopy for the treatment of intermittent upper abdominal pain, which she had been experiencing for a year. A diagnosis of a submucosal tumor (SMT) was made after several preoperative examinations. An endoscopic submucosal dissection (ESD) was performed to remove the lesion, and the specimens were then fixed to conduct the pathologic examination. The results led to the diagnosis of undifferentiated gastric adenocarcinoma with the following general classification: type 0–IIa, a lesion of 2.7 cm × 2.0 cm × 0.5 cm, and no vascular tumor thrombus or nerve invasion. The surrounding mucosa showed mild chronic non-atrophic gastritis. The tumor tissue reached the vertical cutting edge, and no residual cancer tissue was found at the horizontal cutting edge. The immunohistochemistry results showed poorly differentiated adenocarcinoma. Based on the results, the patient underwent distal gastrectomy and abdominal lymph node dissection. Our combined multidisciplinary diagnostic processes and treatments can now be used as a reference for endoscopists. CONCLUSIONS: ESD plays an essential role in the diagnosis and treatment of undifferentiated gastric cancer, and provides a reference for endoscopists.