Appendiceal tumors: retrospective clinicopathologic analysis of appendiceal tumors from 7,970 appendectomies.

BACKGROUND: Appendiceal tumors are rare and often unexpectedly discovered in an acute situation, in which decision-making is difficult. To help define the most appropriate management, a retrospective analysis was undertaken to describe the clinicopathologic behavior of appendiceal tumors, and the literature was reviewed of the management of the different types of appendiceal tumors.
METHOD: From a single center, a histopathologic database of 7,970 appendectomies, all appendiceal tumors, were identified and case notes reviewed. Analysis of clinical presentation, histopathology, operation, and outcome is presented.
RESULTS: During a 16-year period (7,970 appendectomies), 74 patients (0.9 percent) with appendiceal tumors were identified: 42 carcinoid, 12 benign, and 20 malignant. Acute appendicitis was the most common presentation (49 percent), and 9.5 percent were incidental findings. Primary malignant tumors of the appendix were found in 0.1 percent of all appendectomies. Secondary malignant disease was identified in the appendix of 11 patients, most commonly (55 percent) from patients with primary colorectal disease. There was a high incidence of synchronous and metachronous colorectal cancer in all appendiceal tumors: carcinoids, 10 percent; benign tumors, 33 percent; secondary malignancies, 55 percent; primary malignancies, 89 percent.
CONCLUSION: Appendiceal tumors are uncommon and most often present as appendicitis. Most are benign and can be managed by appendectomy, except adenocarcinomas and carcinoids larger than 2 cm, which are most appropriately managed by right hemicolectomy. A suggested management algorithm is provided. Controversy exists over the management of carcinoids 1 to 2 cm in size and adenocarcinoids. All types of appendiceal tumors have a high incidence of synchronous and metachronous colorectal cancer.