• 1% of all appendectomy specimens contain a neoplasm.
• Most common tumor is the carcinoid (0.3%).
• Rare tumors also include:
o benign and malignant mucoceles
o adenocarcinoids or goblet cell carcinoid.
• Carcinoids represent 2/3 of all appendiceal neoplasms.
• Of all those within the GI tract, ½ arise from the appendix.
• They appear yellow and have a surrounding desmoplastic reaction although usually found
• Most carcinoids present in ages 15-29.
• Goblet cell carcinoids typically present at mean age 52 years.
• Mucoceles of the appendix can be either cystadenomas or cystadenocarcinomas.
• They usually obstruct the appendiceal lumen with mucin.
• On CT, one sees a mucin filled lumen with a surrounding calcified wall.
• If a benign tumor causes appendiceal rupture and mucinous ascites, appendectomy is
• If malignant with mucinous ascitesÆ pseudomyxoma peritonei.
• The difference is that in malignant condition there is tumor implantation in peritoneum
with mucin producing cells.
• Appendiceal adenocarcinoma is rare and found unexpectedly at time of appendectomy.
• 50% of these patients have metastases at time of diagnosis.
• Dukes A (mucosa and submucosa) lesions can be treated by appendectomy.
• B and C lesions need right hemicolectomy.
• Usual presentation is that of appendicitis and tumor is found incidentally.
• Most of the time tumor (62%) is found at tip and is not the cause of the appendicitis.
• Can also be diagnosed at time of routine cholecystectomy or benign pelvic surgery.
• Goblet cells often found in diffusely inflamed appendix.
• carcinoids produce serotonin, histamine, kallikrein, bradykinin and prostaglandins.
• Confirmed by 24-hour urinary excretion of 5-HIAA.
o Vasomotor- flushing during stress, alcohol, sex, or large meal.
o Lasts 5-10 minutes begins on face and then goes to trunk.
o Cardiac-endocardial fibrosis of tricuspid and pulmonary valves.
• If have carcinoid syn