Table 1

Proposed interpretations of each combination of different free-floating mucin subtypes according to the route of EUS-FNAB

Route of FNAB with mucin subtypeReported interpretation*
Transgastric with neutral mucinCould support origin from an MCL but cannot exclude contamination from gastric mucosa
Transgastric with acidic or mixed mucinSupports origin from an MCL
Transduodenal with neutral or mixed mucinSupports origin from an MCL provided neutral mucin is not contamination from Brunner’s glands
Transduodenal with acidic mucinCould support origin from an MCL but cannot exclude contamination from duodenal mucosa
  • *Presence of unequivocal dysplasia or ‘mismatched epithelial mucin’ (see main text) overrides these interpretations and is regarded to indicate origin from an MCL.

  • EUS-FNAB, endoscopic ultrasound-guided fine-needle aspiration biopsy; MCL, mucinous cystic lesion.