For most people, the "beer belly" is caused by being overweight. In the case of Hector Hernandez, it was because of a 77-pound tumor found in the back of his abdomen.

Hernandez said that he was still considered a great guy. Before consulting a doctor, he followed a plant-based diet in the hope of losing weight.

There was a problem: he lost weight everywhere except his belly.

"I was basically like a thin person who has a huge belly," said Hernandez in an interview with USA TODAY.

In 2006, he visited a doctor and noted the unusual size of his stomach. Hernandez said the doctor had told him that it was because people were gaining weight differently. In his case, according to the doctor, he went straight to the stomach. "I left it like this."

Earlier this year, the 47-year-old Californian resident saw a new doctor after switching insurance. Since he had been diagnosed with hypertension and diabetes, he wanted a checkup.

By the time the doctor entered for the first visit, it was clear how urgent Hernandez's case had become. "He did not show up, or anything, he just said" oh my God, how long have you been like this, "and he hit my stomach," said Hernandez.

After consulting several specialists, a liposarcoma, a rare type of cancer beginning in fat cells, was diagnosed in Hernandez.

Dr. William Tseng, a sarcoma specialist at the Keck School of Medicine at the University of Southern California and Hernandez surgeon, said that sarcomas typically accounted for about 1% of all cancers, with liposarcoma representing subset of these tumors.

"It's essentially a cancer of the fat," Tseng said in an interview.

Tseng said that one of the complications of treating sarcomas is that the symptoms do not appear as severe. Hernandez said he was suffering from heartburn, but assumed that it was nothing unusual. He also noted a shortness of breath.

Another complication: the connection between sarcoma and the rest of the body. "Over time, the organs are spread apart or the tumor surrounds them, but does not necessarily invade them," said Tseng.

After a six-hour surgery in July, a 27-kg tumor – about the size of a 10-year-old child – was safely removed from the abdomen of Hernandez.

Since then, Hernandez has stated that he was "much healthier now". He must undergo a scan every four months to make sure that the tumor does not reappear and continue these for a few years. His stomach burns have now disappeared, as have his high blood pressure.

"There are so many things I can do now that I could not do before," he said. "I feel like a different person."

A The GoFundMe page has since been created to help Hernandez pay his medical bills.

Follow Brett Molina on Twitter: @ brettmolina23.

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