Acute appendicitis caused by metastatic gastric adenocarcinoma: a case report and literature review.

It is rare that Acute appendicitis (AA) caused by metastatic gastric adenocarcinoma is seen in the clinic. The underling mechanism is not clear, and the prognoses of these patients have been discrepant. Herein, we have presented a case of this disease seen in our clinic and summarized 7 similar previously reported cases. We reported the case of a 33-year-old female patient who presented with gastric cancer (GC) metastasis to the appendix that was found incidentally in the emergency surgery for AA with evidence of multi-site metastases. The final pathology of endoscopic biopsy and positron emission tomography-computed tomography (PET-CT) confirmed late-stage GC with multi-site metastases. Chemotherapy and radiotherapy were taken after diagnosed, and the patient died about 7 months after appendicectomy. We also reviewed 7 case-reports on GC metastasis to the appendix. The metastasis was symptomatic in 4 cases, and appendectomy was performed in all cases. The prognosis of the cases varied considerably. There was a total of 8 cases included in this paper. We discussed the diagnosis and the potential route of appendiceal metastasis from GC. Of the 8 cases, 6 had a history of GC. We also examined the prognosis of the cases and the benefit of performing appendectomy in every gastrectomy.