Kunal Mitra (right), who is trying to develop laser-based diagnosis of skin cancer that could avoid the need for biopsies in some patients, in his laboratory
New Delhi, Jan. 30: In 23 years, Jadavpur-educated American engineer Kunal Mitra has moved from monitoring a blast furnace in a Jamshedpur steel plant to promising the world a novel way to spot skin cancer — within minutes, without biopsies.
Mitra, a professor of mechanical engineering at the Florida Institute of Technology, has developed a technique that uses fleetingly short pulses of laser light to distinguish between normal and cancerous skin cells.
He has demonstrated its potential for diagnosing melanoma — a deadly form of skin cancer — in mice and believes that the laser pulses may eventually be used to detect breast cancer too.
The laser-based cancer detection technology is intended to reduce the number of expensive and time-consuming biopsies by allowing doctors to detect the cancer in their own offices within minutes.
“It won’t replace biopsies, but it could help thousands of people avoid unnecessary biopsies,” said Mitra, who studied mechanical engineering at Jadavpur University before moving to the US for his MS and PhD studies, both at New York University.
“Dermatologists typically do four to 50 biopsies before they detect a single case of melanoma. So, many people have to undergo biopsies without good reason,” said Mitra, who is also the chair of the biomedical engineering programme at FIT.
After three years of studying engineering, just ahead of his fourth year at Jadavpur, Mitra had spent several weeks at summer training watching a blast furnace in operation at a steel plant in Jamshedpur.
The switch from the insides of a steel factory to cancer diagnostics might seem like a dramatic twist in an engineer’s career path, but Mitra believes his passion for heat transfer nudged him into the field of biomedical engineering.
“I always loved heat transfer in mechanical engineering,” Mitra told The Telegraph. “When I began MS in 1991 and PhD in 1993, heat transfer in biological tissues was considered an innovative area, and that led to studies of how laser light interacts with biological tissues.”
Mitra plunged into this line of research about ten years ago, hoping to use laser light pulses to detect breast cancer. But skin cancer being a major problem in Florida and elsewhere in the US, Mitra said: “It was easier to convince funding agencies to support a programme to detect skin cancer.”
The technology uses reflected laser pulses to spot differences between the way normal cells and cancer cells reflect the optical signals. Each laser pulse lasts about 100 picoseconds or ten-billionth of a second. Cancer cells are more absorbing and thus have different optical signatures.
Cancer specialists say any diagnostic technique will have to prove itself to be highly specific and sensitive — in other words, it will have to generate very low rates of false positive or false negative results.
“An optical screening system could help separate the highly suspicious cases from the not-so-suspicious cases,” said Rupinder Sekhon, a senior consultant oncologist at the Rajiv Gandhi Cancer Institute and Research Centre, New Delhi.
“But nothing can replace tissue-based diagnosis (biopsy). When we treat cancers, we just have to understand what we are dealing with, so the tissues have to be examined,” Sekhon, who is not associated with the work at FIT, told this newspaper.
Mitra said a few engineering challenges needed to be overcome before the technology could be tested in humans. “What we have is a table-top set-up: we’ll need to make the system smaller and more compact before we can start studies in humans.”
He is also hoping to refine the technology to detect breast cancer.
“In the US, mammograms (which involve exposure to X-rays) are routinely done in women above 40 years of age,” said Mitra. “This technology may help spot cancer without exposure to ionising radiation.”
The US patents office granted Mitra a patent last year for a laser-based skin cancer detection system. FIT has entered into an exclusive licensing agreement with a company named Hart Rank Investments, which has set up MedPulse, a company to further develop the technology, in Orlando, Florida.