Endosonographic and cyst fluid characteristics of cystic pancreatic neuroendocrine tumours: a multicentre case series

Dig Liver Dis. 2013 Sep;45(9):750-3. doi: 10.1016/j.dld.2013.02.021. Epub 2013 Apr 9.

Abstract

Background: Pancreatic neuroendocrine tumours are uncommon neoplasms which may rarely be cystic. Differentiation from other more common cystic neoplasms may be difficult.

Aims: To describe the morphologic, cytologic, and cyst fluid characteristics of cystic pancreatic neuroendocrine tumours.

Methods: Retrospective analysis of consecutive patients referred for endosonographic evaluation of pancreatic cysts at four centres.

Results: 27 patients (12 males) with cystic pancreatic neuroendocrine tumours were identified. Prior to endosonography, this tumour was suspected in only 2 patients based on presenting symptoms (7.4%). The median cyst size was 35 mm (range 8-80 mm). Wall thickening was identified in 13 cases. The median carcinoembryonic antigen level was 1.25 (range 0.6-500). Fine needle aspiration cytology in 17 of 24 patients confirmed neuroendocrine tumour (71%). In 8 of 9 patients who had needle targeting of the cyst wall, cytology was consistent with neuroendocrine tumour (88.9%). 18 patients underwent surgical resection.

Conclusions: Cystic pancreatic neuroendocrine tumour was rarely suspected, including by cross-sectional imaging. Wall thickening was identified in approximately half of cases on endosonography. Cyst fluid was typically non-viscous with very low carcinoembryonic antigen levels. Targeting the wall during fine needle aspiration had a high diagnostic yield and should be performed.

Keywords: Cyst fluid analysis; EUS; Fine needle aspiration; Neuroendocrine tumours; Pancreatic cysts.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoembryonic Antigen / analysis*
  • Cohort Studies
  • Cyst Fluid / chemistry*
  • Endoscopic Ultrasound-Guided Fine Needle Aspiration
  • Endosonography
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neuroendocrine Tumors / blood
  • Neuroendocrine Tumors / diagnostic imaging
  • Neuroendocrine Tumors / pathology*
  • Pancreatic Neoplasms / blood
  • Pancreatic Neoplasms / diagnostic imaging
  • Pancreatic Neoplasms / pathology*
  • Retrospective Studies

Substances

  • Carcinoembryonic Antigen