A Case of Gastric Neuroendocrine Carcinoma with Disseminated Recurrence 14 Years after Initial Surgery

Gastric neuroendocrine carcinoma (NEC) is a rare disease among gastric cancers, accounting for only 0.1%-0.6% of all cases. This disease is known to have a poor prognosis and a higher risk of recurrence compared to conventional gastric adenocarcinoma. At the age of 44, a 60-year-old female underwent a laparoscopic-assisted proximal gastrectomy for gastric cancer at a previous hospital. Neuroendocrine carcinoma was diagnosed following a postoperative pathological examination based on histological findings and immunostaining results. The patient was followed up without any recurrences. After 14 years, a follow-up contrast-enhanced CT revealed a 9-mm mass on the greater curvature side of the gastric antrum, which was suspected to be lymph node swelling at the previous hospital. After 8 months, she came to our hospital with abdominal discomfort and distention. The CT scan revealed a 55-mm mass, indicating an increase in the previously mentioned mass. At our hospital, the patient underwent open tumor resection. The pathological findings revealed a recurrence of gastric NEC. The patient has been recurrence-free for 6 months following surgery. We present a case of gastric NEC with disseminated recurrence. To our knowledge, this is the first report of a disseminated case in which a recurrent lesion caused by omental dissemination grew in size and infiltrated a portion of the gastric serosa approximately 14 years after the initial surgery.