Callahan & Blaine

The country’s largest health insurer is seeking to toss a federal lawsuit that alleges it wrongly denied coverage for a controversial radiation treatment to a Boston woman with cervical cancer.

Kate Weissman sued UnitedHealthcare earlier this year after it refused to pay for her $95,000 treatment at Massachusetts General Hospital. The treatment, called proton beam radiation therapy, is designed to precisely target a tumor while protecting the surrounding organs.

Now the insurer is asking a judge to dismiss Weissman’s suit, for which class-action status is sought. UnitedHealthcare is arguing that she has failed to make a claim under specific provisions of a federal law that governs employer-sponsored health plans.

“Plaintiff’s Complaint is deficient for multiple reasons,” the insurance company said in an August court filing submitted by Justin P. O’Brien, a partner at Hogan Lovells in Boston.

UnitedHealthcare declined to comment on the lawsuit but reiterated an earlier statement that its medical policies and coverage decisions are based on current scientific evidence.

“We continually review and update these policies and coverage decisions,” spokeswoman Maria Gordon Shydlo said in the statement.

Weissman, a public relations professional who lives in Charlestown with her husband, was diagnosed with cervical cancer in 2015. She received chemotherapy and radiation treatment, but several months later, the cancer had spread to two lymph nodes. Then her doctors recommended proton therapy.

When UnitedHealthcare refused to pay, Weissman appealed the decision several times, but the company stood firm. Weissman’s parents ended up footing the bill for her treatment.

Weissman, cancer-free for three years, said Monday that she’s “more committed than ever” to her lawsuit. “I was not surprised by the response. I was very disappointed with it,” she said.

Proton treatment is controversial because it typically costs at least twice as much as standard radiation — but studies have failed to show that it is superior to standard radiation for most patients.

Insurers routinely refuse to pay for the treatment, though some patients get covered after appealing. Still, health policy experts who have studied proton therapy say it is used more often than it should be, representing waste in the health care system.

Weissman wants her lawsuit to change how UnitedHealthcare makes coverage decisions for its members, said her lawyer, Richard T. Collins of Callahan & Blaine in Santa Ana, Calif.

“UnitedHealthcare argues these are just business decisions, and we can’t sue them over their business decisions,” Collins said in an e-mail. “We believe these are more than just business decisions. . . . UnitedHealthcare members should expect more from their health insurance company.”

Proton treatment has been the focus of previous lawsuits, as well as an ongoing case in Florida involving a patient who was denied coverage to treat his prostate cancer.

The cost of opening a proton treatment center easily can exceed $100 million, and most hospitals don’t offer the treatment. Mass. General has the only center in New England, which it opened in 2001.

If your insurer has denied you or a loved one vital, life-saving treatment, we urge you to join our fight. Contact Rich Collins at 714-241-4444 or rcollins@callahan-law.com for expert legal counsel.

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