VALENCIA ( — A grieving Valencia family spoke out Friday about a rare cancer they said killed their father and was spreading among Vietnam War veterans.

They believed the disease was linked to a parasite that some veterans may have unknowingly picked up during deployment overseas.

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Mike Brown, 68, a retired marine and Los Angeles police officer, died of bile-duct cancer in October, three years after the father of two and grandfather to five was diagnosed with the disease.

His family believed his illness was caused by a parasite he picked up while serving in Vietnam almost 50 years ago.

“It’s easy to swallow it. Not being aware of it and eating it, eating the food there. Never knowing that it was going to kill him,” said his widow, Roxanne Brown.

As his family searched for answers, his son discovered his dad was one of hundreds of Vietnam veterans with the same diagnosis that had possible links to a parasite commonly found in uncooked river fish in Asia.

“It made a lot of sense. I mean, the data coming from Asia and those parts of the world. You’re just more likely to develop this type of cancer in those areas,” said the veteran’s son, Sean Brown.

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“The worms infect an estimated 25 million people in Asia and can be easily erased with a few pills. But untreated, cancer can develop even decades later. The U.S. government acknowledges that liver-parasite flukes, endemic in … Vietnam, are likely killing some former soldiers,” the Associated Press reported in November.

Brown said when her husband first filed a claim with the Veteran’s Administration, it rejected his claim.

“It’s similar to what happened before Agent Orange became a presumptive illness. They were saying it’s not possible. It could be. But more than likely, it isn’t,” she said.

The Browns eventually won a settlement recognizing the cancer was service-related — a week before Mike Brown died.

Now the family has an urgent plea: “If they’re presenting with symptoms like jaundice or fatigue, and they served in Vietnam, it’s important to get in as soon as possible,” Sean Brown said.

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The Vietnam Veteran Memorial Fund will honor Mike Brown in Washington, D.C., this summer along with other veterans who died from service-related illnesses.