Epidemology of Neuroendocrine Tumors in Ontario: A 15-year Population-Based Study.

Introduction: A recent study of the SEER database in the United States showed a 5-fold increase in neuroendocrine tumors (NETs) over the last 30 years. Conflicting reports of incidence trends have been reported worldwide. Aim(s): To describe the incidence and anatomical distribution of NETs in Ontario, Canada. Materials and methods: A population-based study was initiated using the Ontario Cancer Registry, cross-linked with the Registered Persons Database and the Canadian Institute of Health Information Discharge Abstract Database. All cases of NETs were identified in Ontario (> 13 million persons) from 1994 to 2009. Baseline demographic, clinical and outcomes data were abstracted. Results: A total of N=5,619 cases were identified. The incidence rate increased from 2.46/100,000 (95% CI, 2.13-2.83) in 1994 to 5.86/100,000 (95% CI, 5.40 - 6.35) in 2009. The median age was 62 with 50.5% female cases. Bronchopulmonary NETs were the most common (22%), then jejunum/ileum (17%) and rectal (16%). The absolute increase was most pronounced for pNETs (6-fold), rectal (5-fold) and gastric (5-fold) NETs. Metastatic disease was documented in 45% of cases. Conclusion: There appears to be a significant increase of reported cases of NETs in Ontario, Canada, particularly pancreas, rectum and gastric NETs. This supports much of the population-based reports worldwide. Further research is required to understand the impact of this cancer previously perceived to be rare but clearly increasing. [ABSTRACT FROM AUTHOR]