Lawmakers are considering legislation to require health insurers to pay for 3D mammography scans in hopes of improving breast cancer detection.

The 3D imaging, known as tomosynthesis, is the latest technology to detect early breast cancers but many patients must pay out of pocket. Proponents say the technology is better at detecting cancer compared to the two-dimension digital mammography currently covered by health plans.

The House Finance Committee passed Wednesday House Bill 481, which amends the existing health insurance law to include tomosynthesis coverage. The bill will move to the state Senate for consideration.

“I do believe this is a very big deal for women in Hawaii. I had to speak to two young women in their 30s that we diagnosed recently with advanced breast cancer. It brings home how important it is to make an early diagnosis,” said Dr. Scott Grosskreutz, a diagnostic radiologist in Hilo who said Hawaii has the lowest percentage of women with insurance coverage for tomosynthesis in the nation. “The sooner this technology becomes widely available for Hawaii women, the sooner we can reduce breast cancer mortality in our state.”

An estimated 1,180 Hawaii women will be diagnosed with breast cancer this year and 160 will die from the disease, according to the American Cancer Society. The federal government has been paying for tomosynthesis since 2015 for patients with Medicare and Medicaid, the government health insurance programs for seniors and low income, but only some private health plans cover it.

Hawaii’s large Asian population in particular — 57 percent of women — would benefit from the 3D technology, Grosskreutz said, because studies have shown that Asian women have the densest breast tissue of any ethnic group, which limits the sensitivity of mammography. The 3D technology would enable doctors to see tumors hidden in dense breast tissue, he said.

Hawaii Medical Service Association said it is already in the process of making 3D breast imaging a benefit, though it did not specify a time frame.

“Women’s health is important and HMSA has many preventive services for women in our plans. 3D breast tomosynthesis isn’t a universally recognized screening test,” said Dr. Mark M. Mugiishi, HMSA executive vice president and chief health officer. “Our medical directors began reviewing the evidence behind this particular service last year and have reached a conclusion, which results in a change in our policy that’s now going through our process of proper notification of all of our stakeholders.”

Lawmakers in 2004 passed a resolution calling for insurers to cover the latest mammography technology.

“In retrospect, that digital equipment has made a huge difference for many women who have had their breast cancers detected at a curable stage. Enabling access to ‘3D’ mammography with this bill will further improve early detection of breast cancer in our state,” Grosskreutz said. “Medicine’s expensive. There’s definitely a cost to screening but tomosynthesis will increase the cost of mammography exams by about a third, but studies show that tomosynthesis will (also) increase detection of early invasive breast cancer by 40 percent to 50 percent.”