Aim: Primary adenocarcinoma of the appendix is a rare malignancy. This study assessed prognostic factors affecting the clinical outcome in patients with appendiceal neoplasms.
Methods: We performed a retrospective analysis of patients who had appendectomies between 1991 and 2007 at five centers in South Korea.
Results: Overall 55 patients (19 men, 36 women, median age 61 years) were identified. Of these, 37 (67.3%) were mucinous adenocarcinomas, 14 (25.5%) were intestinal-type adenocarcinomas, and four (7.3%) were signet ring cell carcinomas. The distribution of stages was: 26 (47.3%) with localized disease, five (9.1%) with regional disease, and 24 (43.6%) with distant metastatic disease. The overall 3- and 5-year survival rates among all patients were 72.2% and 64.0%, respectively, with 20 deaths during the follow-up period. In a multivariate analysis, high histological grade (hazard ratio [HR]vs low grade 15.7; P = 0.001) and pathological stage (distant vs loco-regional, HR 6.2; P = 0.021) were independent predictors of overall survival. Of the 34 patients who underwent curative resections of primary appendiceal carcinomas, the 3- and 5-year disease-free survival rates were 66.4% and 53.3%, respectively. The recurrence rate was higher in patients with regional lymph node metastasis (HR vs node negative disease 23.4; P = 0.005) and high-grade tumors (HR vs low grade 6.3; P = 0.029). Additionally, a right hemicolectomy reduced the risk of recurrence (HR vs lesser procedures 0.05; P = 0.005).
Conclusion: High tumor grade and advanced stage were significantly predictive of poor survival outcome in patients with primary appendiceal carcinomas.