The idea behind the sKan device is that after human skin has been cooled, cancerous lesions warm back up again more quickly than normal skin. Their higher temperature should be detectable with a heat scanner.
Canadian students have developed an early prototype of a cheap, handheld scanner that could one day help doctors diagnose skin cancer painlessly in their offices.
The team from McMaster University beat out more than 1,000 other ideas from around the world to win this year’s James Dyson Award for design engineering, worth $40,000 US ($51,000 Cdn), with a device called The sKan.
“It’s a very clever device with the potential to save lives around the world,” said inventor James Dyson in a statement. He was one of the three judges who chose the entry from 20 finalists. He’s also the founder of the James Dyson Foundation, the charitable trust that runs the award.
It’s the second time a Canadian team has won in the award’s 13-year history.
The device is still in an early stage of development — the current prototype isn’t actually sensitive enough to detect cancer, according to team member Rotimi Fadiya.
But he’s confident that with his team’s planned improvements to the design, future models will have the potential to save lives.
The sKan team members, left to right, Prateek Mathur, Shivad Bhavsa, Rotimi Fadiya, and, far right, Michael Takla meet with inventor James Dyson, who is second from right, after winning this year’s James Dyson Award.
The idea behind the device is that after human skin has been cooled, cancerous lesions warm back up again more quickly than normal skin or moles.
That’s because cancerous cells grow and divide faster than normal cells, giving them a higher metabolic rate, says Dr. Raimond Wong, chairman of the Gastrointestinal Oncology Site group at the Juravinski Cancer Centre in Hamilton, Ont., and the sKan team’s mentor. Melanoma skin cancer also attracts new blood vessels to grow towards and inside it to supply it with extra energy, and those new blood vessels don’t respond the same way normal blood vessels do, Wong added in an interview with the foundation.
Some researchers have already tested infrared cameras, which can cost thousands to tens of thousands of dollars, to detect the higher temperature of cancerous lesions as they warm up, with some success.
‘$1 apiece’
But the sKan device aims to do that more cheaply using thermistors — tiny electronic components that change their resistance with temperature. Sixteen are arranged in a grid pattern, creating a map of different temperatures in different areas of the sensor.
“The pieces that we’re using you can get for like $1 apiece,” said Fadiya, who is 22. Even smaller, more sensitive thermistors don’t cost more than $10 or $20, he added.
Right now, skin cancer is typically diagnosed first with a visual inspection by a doctor. If a mole looks suspicious, cancer is confirmed or ruled out with a painful biopsy, which involves cutting out a piece of the skin. Because there are a lot of false positives with a visual inspection, one study found that in the U.S. between 1986 and 2001, there were more than 60 biopsies done for every melanoma detected.
Right now, skin cancer is typically diagnosed first with a visual inspection by a doctor. If a mole looks suspicious, cancer is confirmed or ruled out with a painful biopsy, which involves cutting out a piece of the skin.
Wong said the problem is that even trained doctors are “not really that accurate most of the time” at determining which moles are cancerous.
On the other hand, doctors want to be safe — the Canadian Cancer Society estimates that in 2017, 7,200 Canadians will be diagnosed with melanoma skin cancer and 1,250 will die. The survival rate is high for those who are diagnosed early — more than 92 per cent for Stage 1, compared to just 15 to 20 per cent for Stage 4.
That’s what got the sKan team interested in the disease and ways to diagnose it when they were trying to decide on a final year project for their electrical and biomedical engineering program at McMaster, said Fadiya.
Fewer biopsies
Wong said a device that works the way sKan is supposed to would help patients and doctors monitor suspicious moles over time and send the right patients for a biopsy “rather than sending everyone.”
Developing sKan hasn’t been easy. Every thermistor responds a little bit differently to temperature, so getting the calibration right for 16 in a single device is tricky, Fadiya said.
That’s one of the reasons why the device can currently only detect a temperature difference of 0.6 C or more between two locations on the sensor. A recent study suggests that it would need to be sensitive enough to detect a temperature difference of 0.3 to 0.5 C to diagnose melanoma.
The device has also so far only been tested in a gel in the lab, not on real skin lesions.
With the award money, the team hopes to improve the next prototype’s sensitivity with better calibration and more expensive thermistors. They also hope to get it into doctor’s offices for preliminary tests on the skin of patients.
In the meantime, Fadiya said winning the award and flying to the U.K. to meet with Dyson has been a “crazy experience.”
The last Canadian team to win the international James Dyson Award was Waterloo-based Voltera, which created a custom circuit board printer, becoming the 2015 winner. That invention is one of two past Dyson award-winning designs that eventually launched commercially. The annual award is open to current and recent design engineering students around the world. National winners were announced earlier this year.