Before surgery                                 After surgery

A Denver woman who had a massive tumor removed from her body is vowing to work at staying healthy after living through years of embarrassment.

Carolina Sifuentes, 19, weighed more than 550 pounds and her stomach was enormous when she first went to a gym to try to do something about her body.

Sifuentes decided to join Curves, a gym that's exclusively for women, because she says she'd had enough with being vastly overweight. As a student at Metropolitan State College of Denver, some people thought she was pregnant.

"Most of the time I just let them think it because it would be worse to tell them I wasn't pregnant," Sifuentes said tearfully.

She also had difficulty simply moving around and walking to classes.

"I couldn't really see my feet, if I was taking the right step. I didn't want to trip and fall," she said.

Curves manager Rachael Baxter said she immediately thought there was something more going on than just being obese when she met Sifuentes.

"I thought 'I've never seen anything like this before,' so I knew that with her being 19 years old, there must something wrong with her," Baxter said.

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