A woman checking her breast for the presence of concerning lumps.
Nancy Cappello was proactive. When she turned 36, she had a baseline mammogram, a standard medical recommendation in the late 1980s and early 1990s as a comparison tool for future screenings. At 40, Cappello started getting them annually.
Her breast surgeon estimated the cancer had been festering for four to five years under the radar of her annual mammograms.
Six weeks after her 11th-consecutive normal mammogram, she was diagnosed with Stage IIIc breast cancer.
A doctor felt a lump while doing a breast exam during her annual physical and a subsequent ultrasound detected cancer that had spread to 13 lymph nodes. That's when Cappello, then 51, learned she had dense breast tissue, making mammography less likely to detect tumors in her breasts.
She also discovered through her own research that she was among the 40 to 50 percent of women with dense breast tissue — almost half the female population — but medical protocol did not require physicians to inform women of their dense tissue status. If she had known, she said, she would have gotten an ultrasound every year in addition to a mammogram that could have detected the cancer much earlier. Cappello said her breast surgeon estimated the cancer had been festering for four to five years under the radar of her annual mammograms.
Although ultrasound as a cancer screening tool has been available for decades, technological advances are helping doctors find more invasive cancers in women with dense breasts, in turn giving women who know their tissue status the opportunity for earlier detection and treatment.
"We know that the gold standard for breast cancer screening is mammography, but in women with dense breast tissue, up to one third of breast cancers can be missed with this modality alone."
Dr. Georgia Giakoumis Spear, chief of the department of breast imaging at NorthShore University HealthSystem in suburban Chicago and assistant professor of radiology at the University of Chicago, has been a leader in developing standards for the use of new ultrasound technology. She is leading a study to develop more specific national guidelines around the use of Automated Whole Breast Tissue Ultrasound (ABUS), a non-invasive procedure in which sound waves are used to scan breast tissue while a patient lies on her back with her arm over her head.
Approved by the Food and Drug Administration in 2012, ABUS provides higher quality 3D images and faster delivery to provide more accurate results than past ultrasound technology. The scan does not involve radiation, and a practitioner can complete the process in 15 to 20 minutes, from patient preparation to image creation. NorthShore has been using ABUS since 2015, Dr. Spear said, and the technology can improve breast cancer detection in women with dense breasts by up to 55 percent.
"We know that the gold standard for breast cancer screening is mammography, but in women with dense breast tissue, up to one third of breast cancers can be missed with this modality alone," Spear says. "And when we supplement screening with ultrasound in this population of women, we have found a large number of cancers by ultrasound that are not visible on the mammogram."
Mammography should still be used as the first step for breast cancer detection, but if an initial mammogram shows that a patient has dense breast tissue, studies encourage discussion of additional screening with ultrasound.
On a mammogram, dense tissue appears white. So do cancerous masses, making them easy to miss.
A radiologist determines tissue density, according to the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). "A" and "B" breast density categories designate ratios of mostly fatty, or non-dense tissues, while the "C" and "D" categories designate heterogeneously dense and extremely dense tissue, respectively. Such patients would be classified as having dense tissue. Younger women, women with lower levels of body fat and women undergoing hormone therapy are more likely to have C and D breast density.
On a mammogram, dense tissue appears white. So do cancerous masses, making them easy to miss. Fatty tissue, in comparison, appears black, making tumors easier to spot.
The FDA stated among its policy goals for 2018 that it's placing an improved focus on recognizing technological advances to help "ensure women get the most relevant, up-to-date information about their breast density, which is now recognized as a risk factor for breast cancer." An article in the March 2018 Journal of the American College of Radiology recommended supplemental screening for women with higher-than-average breast cancer risk, placing women with dense breast tissue in that category.
To be sure, some in the medical community are reluctant to push for ultrasounds, saying that a mammogram might be enough even if the woman has dense breast tissue. A patient is advised to discuss the option of ultrasound with her physician and they can decide from there.
Access to such information became political for Cappello after her diagnosis in 2004. She said that as she underwent six surgeries, a mastectomy, chemotherapy, radiation and hormone therapy, she asked doctors why they weren't required to inform women of their dense breast tissue status. Her dissatisfaction with their responses led to the formation of Are You Dense, Inc., an advocacy group aimed to inform women of their medical options while working to pass legislation mandating that women know their tissue status. Other legislation has focused on mandating insurance coverage for breast ultrasounds.
Nancy Cappello.
(Courtesy)
Cappello's work led Connecticut to become the first state to pass an information law in 2009, and 35 states now have similar requirements. Depending on the state, the law could mandate that certain language or information about breast density be included in the patient's mammogram results, or require physicians to tell women about dense tissue if their breast density falls in the BI-RADS categories C and D. Other states might require that patients be given general information about breast density and advice to discuss their options with a physician. (Note: There is a chart on Cappello's website that shows what laws exist – or don't – in each state.)
Through her site and social media, she's connected with other women who've lobbied for laws in their states, including Dr. Spear, who recently testified before legislative committees in Illinois as they considered companion bills. The Illinois legislation is expected to be signed into law this summer.
"There should be no excuses," Cappello says. "Women should have this information. There should be no concealing or hiding of her status."
Residents of Fountain Hills, a small town near Phoenix, Arizona, fought against the night sky pollution to restore their Milky Way skies.
Light pollution is defined as the excessive or wasteful use of artificial light.
Light-emitting diodes (LEDs) -- which became commercially available in 2002 and rapidly gained popularity in offices, schools, and hospitals when their price dropped six years later — inadvertently fueled the surge in light pollution. As traditional light sources like halogen, fluorescent, mercury, and sodium vapor lamps have been phased out or banned, LEDs became the main source of lighting globally in 2019. Switching to LEDs has been lauded as a win-win decision. Not only are they cheap but they also consume a fraction of electricity compared to their traditional counterparts.
But as cheap LED installations became omnipresent, they increased light pollution. “People have been installing LEDs thinking they are making a positive change for the environment. But LEDs are a lot brighter than traditional light sources,” explains Ashley Wilson, director of conservation at the International Dark-Sky Association (IDA). “Despite being energy-efficient, they are increasing our energy consumption. No one expected this kind of backlash from switching to LEDs.”
Light pollution impacts the circadian rhythms of all living beings — the natural internal process that regulates the sleep–wake cycle.
Currently, more than 80 percent of the world lives under light-polluted skies. In the U.S. and Europe, that figure is above 99 percent.
According to the IDA, $3 billion worth of electricity is lost to skyglow every year in the U.S. alone — thanks to unnecessary and poorly designed outdoor lighting installations. Worse, the resulting light pollution has insidious impacts on humans and wildlife — in more ways than one.
Disrupting the brain’s clock
Light pollution impacts the circadian rhythms of all living beings—the natural internal process that regulates the sleep–wake cycle. Humans and other mammals have neurons in their retina called intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells collect information about the visual world and directly influence the brain’s biological clock in the hypothalamus.
The ipRGCs are particularly sensitive to the blue light that LEDs emit at high levels, resulting in suppression of melatonin, a hormone that helps us sleep. A 2020 JAMA Psychiatry study detailed how teenagers who lived in areas with bright outdoor lighting at night went to bed late and slept less, which made them more prone to mood disorders and anxiety.
“Many people are skeptical when they are told something as ubiquitous as lights could have such profound impacts on public health,” says Gena Glickman, director of the Chronobiology, Light and Sleep Lab at Uniformed Services University. “But when the clock in our brains gets exposed to blue light at nighttime, it could result in a lot of negative consequences like impaired cognitive function and neuro-endocrine disturbances.”
In the last 12 years, several studies indicated that light pollution exposure is associated with obesity and diabetes in humans and animals alike. While researchers are still trying to understand the exact underlying mechanisms, they found that even one night of too much light exposure could negatively affect the metabolic system. Studies have linked light pollution to a higher risk of hormone-sensitive cancers like breast and prostate cancer. A 2017 study found that female nurses exposed to light pollution have a 14 percent higher risk of breast cancer. The World Health Organization (WHO) identified long-term night shiftwork as a probable cause of cancer.
“We ignore our biological need for a natural light and dark cycle. Our patterns of light exposure have consequently become different from what nature intended,” explains Glickman.
Circadian lighting systems, designed to match individuals’ circadian rhythms, might help. The Lighting Research Center at Rensselaer Polytechnic Institute developed LED light systems that mimic natural lighting fluxes, required for better sleep. In the morning the lights shine brightly as does the sun. After sunset, the system dims, once again mimicking nature, which boosts melatonin production. It can even be programmed to increase blue light indoors when clouds block sunlight’s path through windows. Studies have shown that such systems might help reduce sleep fragmentation and cognitive decline. People who spend most of their day indoors can benefit from such circadian mimics.
When Diane Turnshek moved to Pittsburgh, she found it almost impossible to see a clear night sky because the city’s countless lights created a bright dome of light called skyglow.
Diane Turnshek
Leading to better LEDs
Light pollution disrupts the travels of millions of migratory birds that begin their long-distance journeys after sunset but end up entrapped within the sky glow of cities, becoming disoriented. A 2017 study in Nature found that nocturnal pollinators like bees, moths, fireflies and bats visit 62 percent fewer plants in areas with artificial lights compared to dark areas.
“On an evolutionary timescale, LEDs have triggered huge changes in the Earth’s environment within a relative blink of an eye,” says Wilson, the director of IDA. “Plants and animals cannot adapt so fast. They have to fight to survive with their existing traits and abilities.”
But not all types of LEDs are inherently bad -- it all comes down to how much blue light they emit. During the day, the sun emits blue light waves. By sunset, red and orange light waves become predominant, stimulating melatonin production. LED’s artificial blue light, when shining at night, disrupts that. For some unknown reason, there are more bluer color LEDs made and sold.
“Communities install blue color temperature LEDs rather than redder color temperature LEDs because more of the blue ones are made; they are the status quo on the market,” says Michelle Wooten, an assistant professor of astronomy at the University of Alabama at Birmingham.
Most artificial outdoor light produced is wasted as human eyes do not use them to navigate their surroundings.
While astronomers and the IDA have been educating LED manufacturers about these nuances, policymakers struggle to keep up with the growing industry. But there are things they can do—such as requiring LEDs to include dimmers. “Most LED installations can be dimmed down. We need to make the dimmable drivers a mandatory requirement while selling LED lighting,” says Nancy Clanton, a lighting engineer, designer, and dark sky advocate.
Some lighting companies have been developing more sophisticated LED lights that help support melatonin production. Lighting engineers at Crossroads LLC and Nichia Corporation have been working on creating LEDs that produce more light in the red range. “We live in a wonderful age of technology that has given us these new LED designs which cut out blue wavelengths entirely for dark-sky friendly lighting purposes,” says Wooten.
Dimming the lights to see better
The IDA and advocates like Turnshek propose that communities turn off unnecessary outdoor lights. According to the Department of Energy, 99 percent of artificial outdoor light produced is wasted as human eyes do not use them to navigate their surroundings.
In recent years, major cities like Chicago, Austin, and Philadelphia adopted the “Lights Out” initiative encouraging communities to turn off unnecessary lights during birds’ peak migration seasons for 10 days at a time. “This poses an important question: if people can live without some lights for 10 days, why can’t they keep them turned off all year round,” says Wilson.
Most communities globally believe that keeping bright outdoor lights on all night increases security and prevents crime. But in her studies of street lights’ brightness levels in different parts of the US — from Alaska to California to Washington — Clanton found that people felt safe and could see clearly even at low or dim lighting levels.
Clanton and colleagues installed LEDs in a Seattle suburb that provided only 25 percent of lighting levels compared to what they used previously. The residents reported far better visibility because the new LEDs did not produce glare. “Visual contrast matters a lot more than lighting levels,” Clanton says. Additionally, motion sensor LEDs for outdoor lighting can go a long way in reducing light pollution.
Flipping a switch to preserve starry nights
Clanton has helped draft laws to reduce light pollution in at least 17 U.S. states. However, poor awareness of light pollution led to inadequate enforcement of these laws. Also, getting thousands of counties and municipalities within any state to comply with these regulations is a Herculean task, Turnshek points out.
Fountain Hills, a small town near Phoenix, Arizona, has rid itself of light pollution since 2018, thanks to the community's efforts to preserve dark skies.
Until LEDs became mainstream, Fountain Hills enjoyed starry skies despite its proximity to Phoenix. A mountain surrounding the town blocks most of the skyglow from the city.
“Light pollution became an issue in Fountain Hills over the years because we were not taking new LED technologies into account. Our town’s lighting code was antiquated and out-of-date,” says Vicky Derksen, a resident who is also a part of the Fountain Hills Dark Sky Association founded in 2017. “To preserve dark skies, we had to work with the entire town to update the local lighting code and convince residents to follow responsible outdoor lighting practices.”
Derksen and her team first tackled light pollution in the town center which has a faux fountain in the middle of a lake. “The iconic centerpiece, from which Fountain Hills got its name, had the wrong types of lighting fixtures, which created a lot of glare,” adds Derksen. They then replaced several other municipal lighting fixtures with dark-sky-friendly LEDs.
The results were awe-inspiring. After a long time, residents could see the Milky Way with crystal clear clarity. Star-gazing activities made a strong comeback across the town. But keeping light pollution low requires constant work.
Derksen and other residents regularly measure artificial light levels in
Fountain Hills. Currently, the only major source of light pollution is from extremely bright, illuminated signs which local businesses had installed in different parts of the town. While Derksen says it is an uphill battle to educate local businesses about light pollution, Fountain Hills residents are determined to protect their dark skies.
“When a river gets polluted, it can take several years before clean-up efforts see any tangible results,” says Derksen. “But the effects are immediate when you work toward reducing light pollution. All it requires is flipping a switch.”