Primary appendiceal lymphoma: clinical characteristics and outcomes of 116 patients.

BACKGROUND: Primary appendiceal lymphoma (PAL) is extremely rare with limited data available in literature. In this study, we sought to describe clinical features and identify factors affecting survival in patients with PAL using a large population cohort.

METHODS: Surveillance, Epidemiology, and End Results database was queried for patients with PAL between 1973 and 2012. Patient demographics, tumor characteristics, and outcomes were assessed.

RESULTS: One hundred sixteen patients with PAL were included. The mean age (standard deviation) at diagnosis was 48 y (±22). PAL primarily afflicted males and white race. Diffuse large B-cell lymphoma was the most common histologic subtype (34.5%). Patients with Burkitt lymphoma presented at an earlier age compared with follicular lymphoma and diffuse large B-cell lymphoma (33 versus 59 and 53 y, respectively, [P < 0.001]). Mean overall survival (OS) for the whole cohort was 185 mo with a 5-y survival rate of 67%. No statistically significant survival difference was observed between gender, race and histologic subtypes. Right hemicolectomy conferred no survival benefit over appendectomy and/or partial colectomy (P = 0.501). In multivariate analysis, increasing age at diagnosis (P < 0.001) was associated with increased hazards of death while gender, race, tumor histology, disease stage, and nature of resection were not significantly associated with OS.

CONCLUSIONS: This is the largest series of PALs. Our results demonstrate that age at diagnosis is an independent predictor of poor survival. Gender, race, histologic subtypes have no effect on OS, and hemicolectomy provides no survival benefit over appendectomy and/or partial colectomy. Additional prospective, multicenter studies including details about chemotherapy and immunotherapy are needed to guide management.