Photo/IllutrationThe Asahi Shimbun

  • Photo/Illustraion

Using calculations from a math whiz, a Japanese team developed “microwave mammography” that offers painless breast cancer screenings that are more accurate and take only 10 minutes to complete.

The method involves sliding a device that emits microwaves on the surface of a patient’s breast to determine possible cancerous tumors and provide a 3-D image in an instant.

Mammograms are essential to detect breast cancer at an early stage, but the current method can fill women with dread.

Conventional mammography involves squeezing a breast between two plates and using X-rays that expose the patients to radiation.

It can be an excruciatingly painful experience.

In addition, the X-ray scans may miss cancer in patients with dense breast tissue, common among young women, because both mammary glands and cancer appear as white areas in images on a mammogram, according to experts.

The new method was spearheaded by Kenjiro Kimura, professor of chemical and condensed matter physics at Kobe University.

According to the team, microwave mammography allows technicians to find even a 0.5-millimeter cancerous tumor, a size that has been difficult to detect using conventional methods.

Breast cancer is the most common cancer among women in Japan, and more than 14,000 women die from the disease every year.

Microwaves, which are used in microwave ovens and cellular phones, can pass through fat and mammary glands in the breast and reflect possible cancer tumors after colliding with them.

Taking advantage of such properties, the team said it could determine the location and the shape of cancers by transmitting a microwave of one-thousandth the power of the ones used in cellular phones.

Previously, no screening device using microwaves had been made because a tough question of an applied math theory had to first be solved.

Kimura, a specialist in applied physics, came up with a solution by tackling the conundrum in applied math: the inverse scattering problem.

When radio waves and acoustic waves are transmitted to an object, the waves scatter in every direction.

Leveraging such scattered waves, Kimura could determine the shape of specific objects. In 2012, he found the world’s first formula for solving such shape identification problems.

Through this formula, he developed a method to survey cracks and scratches of a tunnel using microwaves that bounce off the damaged parts.

The study was triggered by a 2012 accident in which concrete slabs fell from the ceiling of the Sasago tunnel on the Chuo Expressway in Yamanashi Prefecture. Nine people were killed after their cars were crushed by the slabs.

Kimura then turned his attention to screening for breast cancer.

Clinical studies with microwave mammography are currently under way at four medical institutions in Hyogo Prefecture.

“This technology can be used only for breasts, but nothing is better for cancer screening than this technology using microwaves,” Kimura said. An outside-the-box idea beyond common sense in medical treatment may make a difference in future breast cancer screening.