EP283 - Incidental Appendiceal Neoplasms in Patients with Colorectal Endometriosis: A Cohort Analysis of Laparoscopic Specimens (2007–2025)

ePoster Presenter(s)

• 

  Maria Fernanda P. de Almeida (she/her/hers)

  Student
  UNICEPLAC
  UNICEPLAC
  Brasilia, Distrito Federal, Brazil

  Disclosure information not submitted.

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Author(s)

• MF

  Maria Eduarda Fernandes Pereira Dias, n/a

  Student
  HUMANITAS
  Taubaté, Sao Paulo, Brazil

  Disclosure information not submitted.
• GC

  Geovanna Calazans Correa, n/a

  Student
  CEUB
  Brasília, Distrito Federal, Brazil

  Disclosure information not submitted.
• JC

  João Victor Calazans Corrêa, n/a

  Medical Doctor
  Universidade de Brasília
  Brasília, Distrito Federal, Brazil

  Disclosure information not submitted.
• Jd

  João Pedro P. de Almeida, n/a

  Auditor doctor
  Hospital Militar de Área de Brasília
  Brasília, Distrito Federal, Brazil

  Disclosure information not submitted.
• 

  Oswaldo de Moraes Filho (he/him/his)

  Consultant Colorectal Surgeon
  University Hospital of Brasília
  University Hospital of Brasília
  Brasilia, Distrito Federal, Brazil

  All disclosed relationships have been reviewed and managed prior to the start of this activity. Any relevant relationships will be listed below. This individual has no financial relationships to disclose
• BA

  Bruno Augusto Alves Martins, n/a

  Colorectal surgeon
  Hospital Universitário de Brasília
  Brasília, Distrito Federal, Brazil

  Disclosure information not submitted.
• FC

  Frederico JS Correa, PhD

  Diretor Médico e Científico
  Clínica Endometriose Brasilia
  Brasília, Distrito Federal, Brazil

  Disclosure information not submitted.

Senior Author(s)

• Rd

  Romulo Medeiros de Almeida, MD, MSc

  Head of Minimally Invasive Surgery
  Hospital Universitartio de Brasilia
  Brasilia, Distrito Federal, Brazil

  Disclosure information not submitted.

Purpose/Background: When resected, appendices affected by endometriosis can harbor incidental neoplasms, yet data on their frequency and characteristics remain limited. This study aimed to describe the histopathological spectrum of appendiceal endometriosis and determine the incidence and type of incidental appendiceal neoplasms in patients undergoing laparoscopic surgery for colorectal endometriosis.

Methods/Interventions: A retrospective analysis of a prospective cohort was conducted at a tertiary multidisciplinary referral center. Consecutive patients who underwent laparoscopic surgery for endometriosis between January 2007 and September 2025 were included. The appendix was systematically inspected intraoperatively, and appendectomy was performed when deformity or suspected involvement was noted. All resected specimens were submitted for histopathological examination.

Results/Outcomes: A total of 1,319 patients underwent laparoscopy for deep endometriosis. Appendiceal deformities were identified in 194 cases (14.7%); the median age was 35 years (SD 6). All resected appendices showed histologic foci of endometriosis, either fibrotic or containing endometrial stroma and/or glands. Five incidental neoplasms were diagnosed (0.38% of the total cohort; 2.6% of appendices resected): three neuroendocrine tumors, one low-grade appendiceal mucinous neoplasm, and one neurofibromatous tumor. None were suspected preoperatively. All lesions were early stage and were adequately treated with appendectomy alone, with no additional oncologic intervention required.

Conclusion/Discussion: Appendiceal involvement in patients with colorectal endometriosis is infrequent, yet appendectomy should be considered when macroscopic abnormalities are detected. Incidental appendiceal neoplasms are rare, and most are early stage and cured with appendectomy alone.

Representative examples of appendiceal endometriosis lesion
Well-differentiated appendiceal neuroendocrine tumor