These varices are very fragile and could easily rupture, causing massive upper GI bleeding.

这些曲张的静脉非常脆弱，容易破裂，导致严重上消化道出血。

Thick blood vessels are problematic because as soon as you make an incision to cut out the tumor, you get massive bleeding.

- 粗血管会带来问题，因为一旦切开肿瘤，就会出现大量出血。