{
  "abstract": "Introduction Duodenal neuroendocrine neoplasms (dNEN) are reported to be increasing in incidence. However, population-based data comparing their incidence and survival are scarce. This study aimed to compare the incidence trends and overall survival (OS) in dNEN in the United States of America (USA) and England.Methods A total of 4,908 patients with dNEN (2011-2022) were extracted from the SEER database (USA), and 1,094 patients (2012-2021) were extracted from the NCRAS database (England). Average Annual Percent Change (AAPC) was calculated to compare incidence between both cohorts. Kaplan-Meier plots and Cox regression analyses were conducted to identify the factors associated with OS in both cohorts.Results In SEER, median age was 64.5 years, and there was a slight predominance of females (50.3%). Most patients were White (52.6%) and lived in metropolitan areas (87.1%). Neuroendocrine carcinoma (NEC) represented 12.6%. Median size was 8 mm. The most common stage was stage 1 (44.3%). Crude AAPC was 4.92%/year. OS of tumour sizes <10, 10-20, and >20 mm were 59%, 58%, and 49% at 10 years, respectively. Multivariable Cox regression showed that advanced age, male sex, tumour size >20 mm, low income, Black race, stage 4 and high grade were associated with poor OS.In NCRAS, the median age was 68 years, and there was a slight predominance of males (55.8%). Most patients were White (75.1%) and lived in urban areas (82.4%). NEC represented 11%. Median size was 11 mm. Crude AAPC was 5.17%/year. The OS of tumour sizes <10 mm, 10-20 mm, and >20 mm were 74%, 52%, and 35% at 10 years, respectively. Size > 20 mm and advanced stage were associated with worse OS in the univariable Cox regression. Moreover, multivariable Cox regression showed that advanced age and high grade were associated with poor OS.Conclusion The incidence of dNEN is increasing over the past decade in the USA and England with similar clinicopathological profiles and outcomes. Advanced age, advanced stage, tumour size >20 mm, and high grade are associated with poor survival of dNEN. Despite some publications suggesting small dNEN have good survival, there is no clear lower size cut-off below which the tumours follow a benign course.",
  "authors": [
    {
      "affiliations": [
        "Hampshire Hospital NHS Trust, Basingstoke, United Kingdom"
      ],
      "name": "Ker Shiong Tan"
    },
    {
      "affiliations": [
        "Hampshire Hospital NHS Trust, Basingstoke, United Kingdom"
      ],
      "name": "Mohamed Mortagy"
    },
    {
      "affiliations": [
        "Hampshire Hospital NHS Trust, Basingstoke, United Kingdom"
      ],
      "name": "Aya Abdelhameed"
    },
    {
      "affiliations": [
        "Hampshire Hospital NHS Trust, Basingstoke, United Kingdom"
      ],
      "name": "Benjamin E White"
    },
    {
      "affiliations": [
        "Hampshire Hospital NHS Trust, Basingstoke, United Kingdom"
      ],
      "name": "John Ramage"
    }
  ],
  "title": "P167 Incidence trends and prognostic determinants of duodenal neuroendocrine neoplasms: comparative analysis of 6,002 patients from SEER (USA) and NCRAS (England)",
  "uid": "4d297335-2197-51d1-8708-87ce3587d434"
}