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An Interview with a Comfort Comp Developer

Using Technology to Alleviate the Pain of Mammography Screenings

This webpage content is intended for Healthcare Professionals only, not for general public.

  • * This article is based on an October 2022 interview with Mr. Takahisa Arai, who worked on development of Comfort Comp from 2016 to 2017

Comfort Comp’s Origins: Talks with Doctors in the Field

I’ve been involved in developing mammography imaging at Fujifilm since 2008. Imaging has a direct impact on the diagnoses that doctors make, so I always base my development on conversations with doctors who treat breast-cancer patients. That gives me a better idea of the issues they deal with in their clinical practice.

The doctors I’ve spoken with almost always voice their concerns about how low Japan’s breast cancer–screening rates are. Breast cancer is a condition that doctors can treat successfully if they can diagnosis the disease early through regular screenings—but in Japan, the screening rates are low. The rate was just 44.9%*1 in 2016, far below the 70–90% levels you see in Europe, the U.S. and other developed countries. The numbers of patients suffering and dying from breast cancer in Japan continue to climb year after year.

  • *1 The information herein includes personal opinions and results from specific facilities. It does not guarantee functionality, performance, or other characteristics of the item concerned.

Why are Screening Rates So Low?: Zeroing in on the Pain Element

What explains the low screening rates? What could we, as a company that manufactures mammography solutions, do to boost them?

According to a 2017 survey of around 1,500 women, the third-most common reason that respondents decided not to go in for a mammogram was that the procedures had been “painful” or seemed that they “would be painful.” With those results indicating that pain could be a significant factor behind Japan’s low screening rates for breast cancer, I started to wonder if we could find a way to alleviate that pain.

How Discovering the Involvement of Hysteresis Sparked Development on Comfort Comp

Hysteresis phenomenon

Getting from there to the development stage wasn’t easy. Firstly, the Comfort Comp development team started reading countless papers on pain, hoping to get a grasp of why pain occurs. I must’ve read 100 or so myself; between the whole team, the number reached into the hundreds. No matter what we were working on at any given moment, it seemed like we always thought about pain somewhere in the back of our minds.

One day, I had a technologist invite me into our lab and position me for a mammogram —it was a chance to learn as much as I could about the procedures involved. To get a good mammogram image, she needs to compress the breast and make it as flat as possible. As a man, I’d only been able to understand mammography indirectly, as a concept; I’d learned about positioning methods from technologists and watched videos, but I’d never actually gone through the process. The technologist just went straight to work, quickly putting my body and face in the right orientation. In almost no time, my chest was being pulled out to the limit, held firmly in place by the technologist’s hand, and then pushed down by a compression paddle. It was a pain like nothing I’d ever experienced before. It was definitely unsettling, even scary, not knowing how bad it was going to get.

Something interesting happened when the technologist's hand pulled away; even though there was nothing pushing on my breast area for a moment, I could still feel the compression like it never left.

That sensation got me thinking, and I headed back to the literature on pain. I went through the relevant discussions and eventually found that breasts show signs of “hysteresis,” a phenomenon in soft substances where the state of the material depends not only on the force currently acting on it but also forces applied previously. Take a shape-memory pillow, for example. If you press the pillow with your hand and then release it, the pillow doesn’t go back to its original state right away. The compression during a mammography examination flattens the breast, so I thought that hysteresis might hold the key to what we were working on; if we could take advantage of the hysteresis phenomenon, we might be able to alleviate the amount of compression in screening procedures. When I came to that realization, the path forward for Comfort Comp got much clearer.

Turning the Concept into a Product

Checking the workflow in the lab

There were plenty of challenges to navigate, however. Two requirements were obvious: the product couldn’t have a negative impact on diagnostic imaging or sacrifice any image quality. Operating within that scope, we had to find a way to reduce pressure as much as possible. But there were other conditions. We also couldn’t change the radiation dose resulting from X-ray exposure, which can have a detrimental effect on patients, nor could we modify the basic shape of the mammography device. Since busy facilities sometimes do imaging on as many as six patients per hour, we knew that our product couldn’t affect the workflow. Everyone feels pain differently, too, which meant that we also had to figure out how to measure pain effectively.

For our evaluations of pain, we sought out hospitals that would help with the effort and talked with doctors there about viable evaluation approaches. The doctors then did assessments for us, providing every cooperating patient with thorough guidance and explanations. Evaluating the imaging results was another important step, which we did by adding calcification mimicking and fiber to a tumor-mimicking phantom for biopsy use, and capturing images before and after using the Comfort Comp to gauge the differences in imaging performance.

Everybody on the Comfort Comp development team leveraged their individual expertise in tackling all the issues at hand, sometimes collaborating across the traditional boundaries separating specializations. Together, we finally put Comfort Comp on track for commercialization.

Since the Product Launch

When the product finally hit the market, we got so much positive feedback from patients: people said that it cut the pain level of a mammogram “in half” and was “completely different” from what the pain they’d experienced in the past. Pain varies from person to person, of course, so some people didn’t notice much of a difference. Some offered their gratitude, thanking Fujifilm for “understanding that mammograms hurt and having the compassion to try to do something about it,” while others commented that the product could get people who “avoid screenings because of the pain” to start coming in for tests. 

Technologists using Comfort Comp were enthusiastic about the product as well. They said: “Comfort Comp promoted their communication with people before actual screenings and made it easier to encourage them to follow through with screenings.” It was so gratifying to know that Comfort Comp was making a real difference in clinical practice.

In Closing

Comfort Comp can help mitigate the pain, anxiety, and discomfort that people associate with breast-cancer screenings—all with hardly any impact on the mammography imaging that doctors depend on or the workflow that technologists follow in completing the necessary procedures. Working together with medical professionals who devote themselves to women’s health, we’re excited to do whatever we can do to give women around the world more reasons to smile.


Japan Society of Breast Health, “Survey on breast cancer screening 2013: Survey report.”

OECD (2017), Health at a Glance 2017: OECD Indicators, OECD Publishing, Paris.

Source: Center for Cancer Control and Information Services , National Cancer Center, Japan