Acute appendicitis as a rare manifestation of gastric cancer metastasis

Acute appendicitis is one of the most common causes of abdominal emergencies worldwide with an annual incidence of 90-100 /100000 in developed countries. Gastric adenocarcinoma is the common gastrointestinal malignancy with a high frequency of metastasis. However the appendix as a site of tumoral dissemination is very rare. Appendiceal tumors are part of a very uncommon neoplasm with a prevalence of 0.7-2.5% which usually present with complicated appendicitis especially in patients with periappendicular abscess.Case presentation:A 65 years old woman was admitted to the emergency department with a two-day history of acute abdominal pain accompanied by nausea and vomiting. The clinical findings and biochemical markers were consistent with the acute appendicitis. Her medical history revealed a well differentiated intestinal type (T3 N1 M0) gastric adenocarcinoma of the antrum 20 months ago. The patient was commenced on three courses of neo-adjuvant chemotherapy regimen followed by partial gastrectomy with free margin and Billroth type 2reconstrcution. Subsequently, three additional courses of adjuvant chemotherapy continued. Taking into all the considerations, the patient underwent abdominal computed topography (CT) which disclosed inflamed appendix with pre-cecal fat stranding and small well-demarcated collection at appendiceal tip without the evidence of other visceral abnormality.the patient underwent open appendectomy. Pathologic report of the appendix veriformis showed tumor cell infiltration from serosa to the muscularis propria of the appendix veriformis consistent with metastatic gastric adenocarcinoma with positive proximal margin (appendiceal stump). Discussion:The appendiceal tumors are very rare with a frequency of less than <0.5% among all the gastrointestinal neoplasm. It should be noted that, there are a few case reports of metastatic tumors of the appendix in the literature compromising less than 0.02 % in which the breast cancer accounts the most commonly known metastasis source and gastric adenocarcinoma accounts the most common cause among the gastrointestinal tumors, respectively. Clinically, appendiceal metastasis presents with symptoms of acute appendicitis which is usually complicated. It is hypothesized to be due to metastatic tumor cells attachment to theserosa and their infiltration through all of the layers of the appendiceal wall leading to luminal obstruction and consequent inflammation.Patients with metastatic appendiceal tumors almost always have a poor prognosis. Currently, the treatment of choice of appendiceal metastasis is appendectomy with supplementary chemotherapy.Here in we aim to highlight the diverse clinical presentation of gastric carcinoma and awareness of the probability rare metastasis involvement.

کلیدواژه ها:

acute appendicitis ، gastric cancer ، metastasis