Dark Empire Sourcebook

A month later, Fett came out of his coma. Dengar didn't want to think about it when he could hear him discussing escape plans with guys ten years dead. Or ten years-should-be-dead. When Fett was on solid food again, they talked.

"I thought nobody had ever gotten out of that thing..."

"They all tried the obvious way out. I didn't. They all went for the opening; I *made* an exit."

...

Oddly, Fett's seizures were because of exposure of thirst. Fett was apparently well fed, since there were all sorts of food proteins in his blood. The trouble was an allergic reaction to the foreign blood types in his system combined with an industrial-grade neurotoxin. He asked the droid about the blood shifting. The only theory it had was the Sarlacc couldn't digest its own food without help, so it fed its blood into the victims, and the blood fed the victims enough nutrients to keep them alive, so the Sarlacc had a constant food source. Meanwhile, the poor victims rolled around and got slowly dissolved.

Dengar shivered as the droid droned on, thinking about the genetic samples in Boba's blood. Some of it matched guys Jabba had iced years ago. All that "digested in the belly of the Sarlacc for a thousand years" yakkity yak was true, and Boba had been in the middle of it. It gave him the chills.