Research suggests the heat, conditions and carcinogens they are exposed to elevate their risk.
Departments across the country have struggled with how to treat the officers when applying for workers' compensation, the health insurance for on-the-job injuries.
In Houston, the firefighters union says 100 percent of cancer workers' compensation claims have been denied by the City of Houston.
The union says the statewide denial rate is 90 percent.
Mark Herring has been a Houston firefighter for 26 years.
A few years ago, he was diagnosed with multiple myeloma and kidney cancer.
His workers' compensation claim was denied.
Today, Herring's cancer is in remission, but he's fighting for workers' comp benefits, blaming the cancer on his job.
"My job gave me cancer and the city just flat out don't care," he said.
The city denied his cancer claim, and initially denied Margaret Roberts' claim too.
Daniel Roberts, Margaret's widower, told ABC13 Eyewitness News last summer, "I had to sit there for almost five years and watch her die daily."
Margaret Roberts spent many of her last days fighting for benefits.
Daniel had to fight the city for years after his wife died. He finally beat the city on appeal.
The cancers that struck Margaret Roberts and Herring have been linked across the country to risks from fire fighting, but up until now, were not recognized that way in Texas.
Texas' list of fire fighting related cancers was one of the shortest, but if Governor Abbott signs a bi-partisan bill that recently passed the state legislature, that's about to change.
Houston Fire Fighters Union President Marty Lancton told reporters Wednesday, "This effort is intended to help fix the broken worker's compensation system, which denies for example, 90 percent of firefighters' cancer claims."
The bill would add eight cancers to the list of fire fighting related cancers in Texas, and force cities to prove fire fighting was not a cause of their cancer.
Under current law, firefighters have to prove it was related to their job.
That change in so-called presumption is one firefighters have pushed for.
The list now links the following cancers to fire fighting in Texas: stomach, colon, rectum, skin, prostate, testis, brain, non-Hodgkin's lymphoma, multiple myeloma, malignant melanoma and renal cell carcinoma.
Governor Abbott has not yet signed the bill.
The new law is not a guarantee of benefits, but fighters fighting to save themselves after years of helping Houstonians, say the move by lawmakers is step in the right direction.
Herring told lawmakers who worked to pass the bill, "This is the beginning and I thank you all very much for what you've done."
Last summer, ABC13 Eyewitness News Investigates examined the way the city mourned a Houston firefighter.
When Margaret Roberts died, the city called her cancer death in the line of duty.
When she fought for Workers Compensation, the city fought her for years.
Read more about our coverage on the struggles injured police officers and firefighters face fighting for workers' compensation benefit.
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