Case report: neuroendocrine tumour causing torsion of the appendix in an adolescent—a rare and unexpected twist

Introduction

Neuroendocrine tumours of the appendix are rare in the paediatric population, with an incidence of 1 in 10,000. They tend to be diagnosed incidentally following appendicectomy for suspected or confirmed appendicitis. The rarity of appendiceal neuroendocrine tumours in children and adolescents has led to an over-reliance of adult-based guidelines, which have been criticised as being too surgically aggressive as these tumours have excellent prognosis in the paediatric population. We report a case of a torted appendix caused by a neuroendocrine tumour lead point resulting in appendicitis. This case report highlights the challenges of managing appendiceal neuroendocrine tumours in children and the need for the development of paediatric-specific guidelines for their management. We present this article in accordance with the CARE reporting checklist (available at https://ls.amegroups.com/article/view/10.21037/ls-24-1/rc).

Case presentation

A 14-year-old female presented to the emergency department with a 2-day history of migratory right lower quadrant pain. Her pain was associated with nausea but no vomiting. She described subjective fevers with chills. The patient had previously presented to another emergency department 24 hours prior to her current presentation and was discharged with a presumptive diagnosis of gastroenteritis. Besides intermittent constipation, the patient’s past medical history was unremarkable. Her immunisation status was up to date. She had no prior surgeries or endoscopy. She denied ever been sexually active and had a negative serum beta-human chorionic gonadotropin (bHCG).

On examination, the patient’s abdomen was soft but tender in the right lower quadrant. She did not have any signs of peritonism. Her blood test demonstrated a normal white cell count (4.4×10⁹/L) and a mildly elevated C-reactive protein (CRP) (12.3 mg/L). She underwent an inpatient ultrasound examination of the abdomen, which failed to visualise the appendix and demonstrated no secondary signs of appendicitis this is despite an outpatient abdominal ultrasound from the previous day that was later reported as showing a convoluted and dilated (9 mm) appendix.

Given the patient’s ongoing pain and recurrent presentation, a decision to proceed with a diagnostic laparoscopy and appendicectomy was made. Intraoperatively, the appendix was found to be torted around the mid-body with some associated mild injection (Figure 1). An appendicectomy (appendectomy) was performed with excision of mesoappendix along the entire length of the appendix. The appendiceal artery was controlled with electrocautery. The patient made an uneventful recovery and was discharged the following day.

Figure 1 Laparoscopic appearance.

The removed appendix specimen is shown in Figure 2. On histopathology (Figure 3A-3C), a well differentiated, grade 2 neuroendocrine tumour identified by nests of monotonous cells with speckled chromatin, diffuse strong staining for synaptotrophysin (Figure 3C) and chromogranin A (Figure 3B) was demonstrated with a mitotic count <1 per 10 high power field (HPF) and mildly elevated Ki-67 index of 4%. The proximal margin was clear of tumour by at least 4 mm. There was extension of tumour through to the serosal surface (pT4) and evidence of perineural invasion. No vascular invasion was identified. The patient was discussed at the institutional colorectal Tumour Board meeting. Whilst further surgery (right hemicolectomy) was considered, a conservative approach of regular surveillance was favoured due to a lack of evidence of a benefit to further surgical resection in this case. The patient’s adolescent age was also taken into consideration. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from patient’s parent/guardian for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Figure 2 Macroscopic specimen.

Figure 3 Histopathology (A: H&E staining, B: chromogranin A staining, C: synaptotrophysin staining; magnification: ×10 for A and B; ×20 for C). H&E, hematoxylin and eosin.

Discussion

We report a rare case of appendicitis caused by torsion of the appendix from a neuroendocrine tumour lead point. While torsion of the appendix is not uncommon, there is currently no reported cases of one caused by a neuroendocrine tumour. Neuroendocrine tumours of the appendix are typically diagnosed on histopathology following appendicectomy for appendicitis. They are rare, with an incidence of 1 in 10,000. They represent approximately 80% of neuroendocrine neoplasm (NEN) diagnosed in children. NEN’s have had a 7-fold increase in incidence since 1973 (1).

Given the rarity of neuroendocrine tumours of the appendix in children and adolescents, there is currently a lack of definitive guidelines on how to manage these patients. This has led to an over-reliance of adult-based guidelines. A retrospective review of two centres in the United Kingdom over a 5-year period demonstrated varied management strategies for appendiceal neuroendocrine tumours, largely based on adult guidelines (2). The prognosis of the paediatric population in this study was excellent with no deaths recorded. The authors felt that many patients were undergoing unnecessary surgery, highlighting the need to develop a paediatric-specific guideline for neuroendocrine tumour of the appendix outlining clearer indications for surgery.

The decision not to proceed with a right hemicolectomy for our patient was based on published evidence suggesting that the importance of surgery in paediatric patients is overstated. Multiple studies have confirmed the excellent prognosis of appendiceal neuroendocrine tumours in children with no survival benefit from right hemicolectomy described (2,3).

Conclusions

We report the first case of a torted appendix caused by a neuroendocrine tumour lead point. Neuroendocrine tumours of the appendix in the paediatric population are rare. Management is primarily based on adult guidelines, but this has been criticised as being too surgically aggressive. The prognosis of appendiceal neuroendocrine tumours in children and adolescents is excellent. There is a need to develop paediatric-specific guidelines for the management of appendiceal neuroendocrine tumours to reduce unnecessary surgery.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the CARE reporting checklist. Available at https://ls.amegroups.com/article/view/10.21037/ls-24-1/rc

Peer Review File: Available at https://ls.amegroups.com/article/view/10.21037/ls-24-1/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://ls.amegroups.com/article/view/10.21037/ls-24-1/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from patient’s parent/guardian for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Dasari A, Shen C, Halperin D, et al. Trends in the Incidence, Prevalence, and Survival Outcomes in Patients With Neuroendocrine Tumors in the United States. JAMA Oncol 2017;3:1335-42. [Crossref] [PubMed]
2. Henderson L, Fehily C, Folaranmi S, et al. Management and outcome of neuroendocrine tumours of the appendix-a two centre UK experience. J Pediatr Surg 2014;49:1513-7. [Crossref] [PubMed]
3. de Lambert G, Lardy H, Martelli H, et al. Surgical Management of Neuroendocrine Tumors of the Appendix in Children and Adolescents: A Retrospective French Multicenter Study of 114 Cases. Pediatr Blood Cancer 2016;63:598-603. [Crossref] [PubMed]