Warning: this story contains a graphic image of a 35 kg tumor.
It seemed that every pound went directly to his stomach.
Héctor Hernández said that he has always been "a big guy", so he did not notice a problem until a couple of years ago, when his arms and legs began to decrease, while his stomach grew.
The 47-year-old man from Downey, California, said he also started struggling with heartburn and constipation and noticed that sometimes it was hard to catch his breath.
At 300 pounds (136kgs), he said, strangers had begun to look, and friends were telling jokes about his "beer belly," even though he said he rarely drank things.
When he first mentioned the problem to a doctor, he said, the doctor ignored him and told him that some people only weigh differently than others.
"I thought I was fat," Hernandez said in a telephone interview Tuesday with The Washington Post.
But Hernandez said his stomach still felt "heavy" and "hard" to the touch, so he got a second opinion.
Ultimately, he said, he was diagnosed with a retroperitoneal liposarcoma, a rare but cancerous tumor that forms in fat cells, according to the Mayo Clinic.
Doctors do not know when the tumor started to grow.
But he weighed 35kgs, according to his surgeon.
Hernandez said he did not know how to feel about the tumor or the surgery needed to remove it.
At first, he said, he was "surprised" and "confused", but also relieved that he finally knew what was wrong.
"I received a lot of support and prayers from family and friends," he said, noting that they are raising funds to help him recover. "I finally left it in the hands of God."
Hernandez's surgeon, William Tseng, an oncologist and assistant professor at the Keck School of Medicine at the University of Southern California, said that liposarcomas develop over time and can grow to massive sizes, although they do not tend to extend to cause big problems. Tseng, who specializes in sarcomas, said that throughout his career, he has surgically removed dozens of them, which is usually between 20 and 30 pounds.
"This is probably the biggest one I eliminated," he told The Post, speaking about Hernández's tumor.
During a one-hour surgery during the summer, Tseng removed the tumor, which he said avoided the main blood vessels of Hernandez and most of the organs, although he had to cut a kidney that had been damaged. Tseng said that bleeding is the greatest risk associated with surgery and that patients may die at the operating table, but there were no complications in Hernandez's case.
The surgeon said Hernandez will not need to undergo chemotherapy or radiation, but because the liposarcomas often come back, Hernández must undergo follow-up examinations periodically to monitor the situation.
"I was very lucky," Hernandez said.
Now, Hernandez said he feels "totally different," more energetic and much lighter.