A mysterious finding in the sputum pot

A middle aged patient suddenly felt as he was choking and retched up this lesion to the horror of a nearby doctor.
WHAT HAS THE PATIENT BROUGHT UP?

Explanation

This beautiful, translucent polyp was sent for analysis and our pathologists rather drily reported: 'Nasal polyp'.   With hindsight, I guess that any sort of fibrovascular polyp, dislodged from the oesophagus would have appeared more 'solid' than this semi-see-through polyp.  However, you would have thought that the patient could have volunteered something like;  " - I can breath better through my nose now", giving the hastily summoned doctor a clue !  ​