Doctors successfully removed a 47-pound tumor from a woman in Tucson, who thought she had just gained weight.

KTVK reported that Marcey DiCaro actually had a 47-pound sarcoma, which doctors were able to remove in a complex 10-hour surgery.

In April, Dr. Tun Jie and his team at the University of Arizona Medical Center performed the operation. The procedure required the surgeons to remove DiCaro’s kidney and gall bladder because of the massive growth.

The New York Daily News noted the tumor was initially discovered growing in her vena cava, the body's largest vein that transports blood to the heart.

After the surgery, she was elated to see the loss of what she thought was belly fat.

"The first time I woke up, I looked down and I thought, 'Oh my God, I don't have that huge belly anymore," she said.

DiCaro was in the hospital for a couple of weeks post-operation, but has since returned to her home and recovered nicely.

CBS 5 - KPHO