"I saw what chemo did to my Grandma," Cantu said. "I was scared and did not want to make her [Penny's] life not worth living, sick all the time. But chemo doesn't affect cats the same way."
At first, Penny did well with her chemotherapy pills, receiving one every three weeks.
"She was eating, playing with the other cat," Cantu said. "I thought, 'Oh my God, maybe she is going to be all right. It's fatal, but she could live another five to seven years."
But then Penny took a bad turn. An ultrasound in November showed the tumor had doubled in size, blocking her intestines.
"We had to make the decision," Cantu said. "It was horrible and we felt horrible. But it was time to help her because she had nothing left. She was just ready to go."
Penny died Nov. 30. Family, friends and even co-workers sympathized with Cantu.
"Nobody said, 'It's just a cat,'" Cantu said.