Police found the Boston terrier in a corner of the chapel at Hoag Hospital in Newport Beach, covered in tumors — about 300 of them.
A rubber band was twisted tightly around one tumor larger than a golf ball on her jaw and her eye was severely ulcerated, the Orange County district attorney's office said.
It's not clear how Pasha got to the chapel; she wasn't wearing a leash. Witnesses saw her wander in, alone, through the hospital's main entrance.
Now, Pasha's owner is facing animal cruelty charges.
Prosecutors charged Victorville resident Mary Sodaro, 52, with one felony count of cruelty to animals and one misdemeanor count each of failure to care for an animal and allowing an animal to roam free on a public street, officials said.
She has pleaded not guilty to the charges.
Authorities identified the owner when she called Newport Beach animal control officers looking for her dog.
Sodaro allegedly admitted to placing the rubber band on the tumor and "failing to humanely treat" the dog's issues, the district attorney's office said. She thought her remedy would cut off blood circulation, officials said, and cause the tumor to fall off.
In recent months, Sodaro had twice taken Pasha to a vet, but allegedly refused to allow her to be treated. During one visit days before Pasha was found at the hospital chapel, officials said, a vet offered to euthanize the dog for free because of the "irremediable pain and suffering" she faced.
It's unclear when the rubber band was applied, but it was there "long enough" that the tumor continued to grow over it, said Deputy Dist. Atty. Jennifer Malone.
Pasha was eventually euthanized, days after she was found.
During a necropsy, a vet found that the rubber band had become embedded in the tumor and caused a skin infection. The tumor had grown so large that it affected Pasha's nasal passages, Malone said.
If convicted of all the charges, Sodaro faces a maximum of three years and six months in state prison.