Introduction Small bowel neuroendocrine tumours (SBNETs) are regarded as relatively indolent cancers. A TNM staging system designed by European NET Society (ENETS) was designed to help stage these tumours to enable ease in classification of these tumours.1 This study aims to demonstrate whether the TNM stage and grade of tumour predicts survival in this cohort of patients. The cause of death is also analysed.
Aim To retrospectively stage patients with known small bowel primary NETs and see whether survival is dependent on stage and grade of disease. The cause of death in patients with small bowel NETs was also analysed.
Methods A total of 138 patients with SBNETs were identified. Primary site: Duodenal 2.1% (3), Jejunal 2.9% (4), ileal 95% (131). Patients with radiologically, endoscopically or surgically proven SBNETs were included in this study, patients with unknown primary were excluded. A total of 623 patient year's follow-up, with a mean duration of follow-up of 5 years. The median age 61 years (range 24–84). Statistical analysis was performed using GraphPad Prism 5.1.
Results TNM staging and follow-up data were available in 118 cases. Due to low numbers of Stage 2 and 3 tumours these were group together for comparison. There were four cases with stage 2, 23 cases with Stage 3 and 91 cases with stage 4 small bowel NETs. Kaplan–Meier plots were constructed these demonstrated a significant difference in survival between patients with different stage of disease (p=0.03). There was no significant difference in survival between stage 2 and stage 3 diseases. There was a significant survival difference between G1 (Ki67 ≤2) vs G2 (Ki67 3–20) p=0.049. The overall 5-year and 10-year survival was 79.5% and 48.5% respectively for all patients independent of stage of disease. Of the patients that died the median time to death from diagnosis was 3 years (range 0–14). The cause of death was related to tumour burden in 50% (22 patients), carcinoid heart disease in 11.3% (five patients), post intervention (one case surgery, one case post-embolisation) 4.5%, small bowel obstruction or perforation 13.6% (six patients) and non-tumour related deaths in 24.5% (9) patients.
Conclusion This study demonstrates the overall 5-year and 10-year survival is higher than that published in the SEER data.2 The cause of death demonstrates the non-tumour or disease related deaths account for 24.5% of cases. There is significant survival difference between Stage IV disease and Stage II and III. There was no significant difference in survival between stage II or III. Low grade tumours Ki67 ≤2% was associated with better survival than Ki67 3–20. No patients had a Ki67 >20; therefore no analysis could be performed.
Competing interests None declared.
References 1. Rindi G, Klöppel G, Couvelard A, et al. TNM staging of midgut and hindgut (neuro) endocrine tumors: a consensus proposal including a grading system. Virchows Arch 2007;451:757–62.
2. Yao JC, Hassan M, Phan A, et al. One hundred years after “carcinoid”: epidemiology of and prognostic factors for neuroendocrine tumors in 35,825 cases in the United States. J Clin Oncol 2008;26:3063–72.