Management and Outcomes of Hospitalized Patients With Primary Neuroendocrine Tumor and Non-Neuroendocrine Tumor Appendiceal Cancers in the United States

BACKGROUND: The incidence of appendiceal cancers continues to rise at a very rapid pace. Although surgery has a central role in the management of appendiceal tumors, literature is lacking regarding the pattern and predictors of surgical treatment for patients with appendiceal cancers. We aimed to describe the surgical treatment for patients with appendiceal cancers, with emphasis on utilization based on histology. METHODS: Hospitalized patients with appendiceal cancer in the US between 2006 and 2010 were included in the study. The Nationwide Inpatient Sample database maintained by the Agency for Health Care Research and Quality was employed for univariate and multivariate testing to identify factors significantly associated with patient outcome. RESULTS: A total of 3,799 patient discharges were identified over the 5-year period covered by the study. Neuroendocrine tumor (NET) was the diagnosis in 291 (7.66%) patients and non-NET in 3,508 (92.34%) patients. The mean age was 56.8 years (± SD 14.6), with female predominance (54.73% vs. 45.27%). NET patients were younger than those with non-NET (50.7 vs. 57.4 years; P < 0.001). NET patients were more commonly treated with appendectomy compared to non-NET (OR: 1.59; 95% CI: 1.23 - 2.07; P < 0.001). Hyperthermic intraperitoneal chemotherapy (HIPEC) was used in 8.5% of all the cases, mostly in non-NET histology (91% vs. 8%). Majority of the patients treated with HIPEC had no co-morbid medical illness (60%), and received care at high volume hospitals located in urban areas. There was a very low incidence of in-hospital mortality (2.5%). CONCLUSIONS: The described surgical utilization pattern should prompt more research focusing on barriers to appropriate surgical debulking and HIPEC utilization in non-NET appendiceal cancers.