What is the most common tumor of the appendix?
Carcinoid is the most common tumor of the appendix, and the appendix is the most common site of carcinoid tumors.
Most large series report an incidence of 0.2 to 0.3 in appendectomy specimens.
Simple appendectomy is appropriate for distal tumors that are less than 1 cm in size.
If the tumor is greater than 2 cm or has extension into the mesoappendix or base of the cecum, formal right hemicolectomy is indicated.
For tumors between 1 and 2 cm that do not involve the base of the appendix, factors such as lymphovascular invasion and mitotic activity influence management decisions and should be referred to a tertiary care center.
It is important to note that not all carcinoid tumors are malignant.
The most common malignant tumor is mucinous adenocarcinoma, composing more than 60% of all appendiceal malignancies.
A mucocele is the second most commonly encountered tumor of the appendix, in which a distended appendix is secondary to obstruction of the appendiceal orifice by mucoid material. Cysts smaller than 2 cm are almost always benign, whereas larger tumors may harbor malignancy.
Rupture of these cysts may spread epithelial cells in mucoid fluid throughout the peritoneum, or pseudomyxoma peritonei of appendiceal origin.