BACKGROUND: An increased incidence of neuroendocrine tumors (NETs) has been reported worldwide, but the reasons underlying this rise have not been identified. By assessing patterns of metastatic presentation, this study sought to examine the epidemiologic characteristics of NETs and the contribution of early-stage detection to the rising incidence. METHODS: A population-based retrospective cohort study was conducted with prospectively maintained databases linked at the Institute for Clinical Evaluative Sciences. Adult patients with a NET diagnosis from 1994 to 2009 in Ontario, Canada were included. The main outcomes included the overall and site-specific incidence, proportion of metastatic disease, overall survival (OS), and recurrence-free survival (RFS). RESULTS: Five thousand six hundred nineteen NET cases were identified. The incidence of NETs increased from 2.48 to 5.86 per 100,000 per year. Metastases were found in 20.8% at presentation and in another 38% after the initial diagnosis. The proportion of metastases at presentation decreased from 1994 to 2009 (from 29% to 13%). Therefore, although the incidence of all NETs increased, the overall incidence of metastases did not change (0.63-0.69 per 100,000 per year). The 10-year OS rate was 46.5%, and the RFS rate was 64.6%. In addition to the primary tumor site, independent predictors of worse OS included an advanced age (P <.0001), male sex (P <.0001), a low socioeconomic status (P <.0001), and rural living (P 5 0.049). CONCLUSIONS: The incidence of NETs has markedly increased over the course of 15 years. This is the first study to provide evidence suggesting that the increase in the incidence of NETs may be due to increased detection. In addition to tumor characteristics, low income and rural residency portend worse survival for patients with NETs. Cancer 2015;121:589-97.

Pancreas cancer (PC), a highly aggressive tumour type with uniformly poor prognosis, is an exemplar of the classical view of cancer development based on stepwise progression1. The current progression model, based on analyses of precursor lesions termed pancreatic intraepithelial neoplasm (PanINs) lesions, makes two predictions: 1) PC develops through a particular sequence of genetic alterations2–5 (KRAS > CDKN2A > TP53/SMAD4); and 2) the evolutionary trajectory of PC progression is gradual because each alteration is acquired independently. One shortcoming of this nearly two decade old contention is that clonally expanded precursor lesions have been identified that do not always belong to the tumour lineage2,5–9, indicating that the evolutionary trajectory of the tumour lineage and precursor lesions can be divergent. This prevailing view of tumourigenesis has contributed to the clinical notion that PC evolves slowly and presents at a late stage10. However, the propensity for this disease to rapidly metastasize and the inability to improve patient outcomes despite efforts aimed at early detection11, argue that PC progression is anything but gradual. By tracking DNA copy number changes and their associated rearrangements from tumour-enriched genomes using novel informatics tools, we found that PC tumourigenesis neither is gradual nor follows the accepted mutation order. Two-thirds of tumours harbour complex rearrangement patterns associated with mitotic errors, consistent with punctuated equilibrium as the principal evolutionary trajectory12. In a subset of cases, the consequence of such errors was the simultaneous, rather than sequential, knockout of canonical preneoplastic genetic drivers that likely set-off invasive cancer growth. These findings challenge the current model of PC tumourigenesis and provide novel insights into the mutational processes giving rise to these aggressive tumours.

The hospital admission rates for complications following transrectal ultrasound guided prostate biopsy have increased dramatically during the last 10 years primarily due to an increasing rate of infection related complications.