Adenocarcinoma of the Appendix and a Meckel’s Diverticulum in a Case of Acute Appendicitis

Accessible online at: www.karger.com/onk Fax +49 761 4 52 07 14 E-mail Information@Karger.de www.karger.com Primary malignant tumours of the appendix are found in 0.9–1.4% of all appendectomy specimens. They are classified by most authors into 5 groups: mucinous adenocarcinoma, colonic type adenocarcinoma, signet ring cell carcinoma, malignant carcinoid, and adenocarcinoid (goblet cell carcinoid). The incidence of appendiceal adenocarcinoma is 0.08% [6]. The peak incidence is in the 6th decade, similar to colorectal carcinoma, and there is a slight male predominance. Adenocarcinoma with signet ring cells – which is the most aggressive of all appendiceal adenocarcinomas and has the worst prognosis – represents 4–11% [1, 4, 5]. It is mostly diagnosed intraoperatively, or postoperatively based on histological examination. More than 50% of patients present with acute appendicitis, but periappendiceal infiltration, palpable abdominal mass, intestinal obstruction, or some other intra-abdominal pathology can also be present. Imaging investigations (plain X-ray of the abdomen or abdominal ultrasonography) are usually of little use for diagnosing the condition. The treatment of choice is right hemicolectomy. In specific cases, a simple appendectomy may be performed. However, according to most recent guidelines, right hemicolectomy should be performed with all non-carcinoid tumours as well as carcinoids measuring > 2 cm [4]. The overall 5-year survival rate, depending on tumour grade and stage, speaks for hemicolectomy (45 and 63%, respectively, compared to 20% with simple appendectomy) [7, 8]. Simple appendectomy can be performed only in the case of a well differentiated adenocarcinoma invading the submucosa or a poorly differentiated adenocarcinoma invading the mucosa, provided the appendiceal stump is not involved. This includes tumours of TNM stage T1 and T2, or stage Dukes A. These stages do not occur very often due to the tendency to metastasize lymphatically and hematogenously at an early stage [9]. Lymph node metastases are present in 45% of patients at the time of diagnosis [5]. Dear Editor,