459P - Follow-up and recurrence in resected gastroenteropancreatic neuroendocrine tumours: A population-based study

Date 10 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Neuroendocrine Cancers
Endocrine Cancers
Presenter David Chan
Citation Annals of Oncology (2017) 28 (suppl_5): v142-v157. 10.1093/annonc/mdx368
Authors D. Chan1, E. Segelov2, L. Moody3, N. Liu4, H. Fischer4, P. Austin4, S. Singh1
  • 1Medical Oncology, Sunnybrook Odette Cancer Center, Sunnybrook HSC, M4N 3M5 - Toronto/CA
  • 2Medical Oncology, Monash University and Monash Health, Melbourne/AU
  • 3Ihpme, University of Toronto, Toronto/CA
  • 4Biostatistics, Institute of Clinical Evaluative Sciences, Toronto/CA



Neuroendocrine tumours (NETs) are uncommon. Little data exist to guide follow-up in resected disease, with no consensus regarding the optimal follow-up frequency or modality. Follow-up imaging regimens are extrapolated from other gastrointestinal tumours. As NETs are heterogeneous, this may result in both over-use and underuse of investigations in patients.


A population-based retrospective cohort study using linked data from the Institute for Clinical Evaluative Sciences and the Ontario Cancer Registry (capturing more than 99% of incident cases in Ontario) was conducted to evaluate patients diagnosed with gastroenteropancreatic NETs in Ontario, Canada from 1994 to 2012. Recurrence-free survival and the frequency of cross sectional imaging (abdominal computed tomography (aCT), magnetic resonance imaging (aMRI) and ultrasound (aUS)) were the main outcomes.


Nine hundred and thirty-six patients were identified with median follow-up 47 months. The mean age was 59, 51% were female, and distribution of primary cancers was: small intestine 47%, pancreas 20%, large intestine 21%, rectum 6.4%, stomach 6.0%. The median survival time to a composite outcome of recurrence or death was 7.2 years, and 9.5 years if censoring on death. The cumulative incidence of recurrence was 8.4% (95% CI 6.8% to 10.3%) within one year, 33.7% (95% CI 30.4% to 36.9%) within five years, and 48.5% (95% CI 44.4% to 52.4%) within 10 years. The rate of recurrence significantly increased with age (HR = 1.529 for age 50-70 compared to 


Unlike colon cancer, significant numbers of NETs recur between 5-10 years after curative surgical resection. These data support the lengthening of follow-up for resected NETs to a minimum of 10 years. Future research should focus on the impact of imaging on early detection of recurrence and survival outcomes.

Clinical trial identification

Legal entity responsible for the study

Sunnybrook Research Institute




D. Chan: Travel support from Novartis; honoraria from Ipsen. E. Segelov: Honoraria from Roche, Bayer, Ipsen and Pfizer; research funding from Merck Serono and Ipsen; travel support from Roche and Ipsen. S. Singh: Honoraria and travel funding from Ipsen, Pfizer and Novartis. All other authors have declared no conflicts of interest.