Laser to Diagnose Melanoma?
The recent death of acclaimed author and neurologist Oliver Sacks (author of best-selling book “The Man who mistook His Wife for a Hat”) came as a great shock for many. His death was caused by melanoma of the eye, which then prolifically spread to his liver, becoming terminal cancer.
How is Melanoma Diagnosed?
Melanoma skin cancer is rare and dangerous, can also begin in the eyes and mouth - although it predominantly affects the skin (including under the nails). Early detection of melanoma plays a pivotal role in treatment, as this skin cancer type is known to metastasize (spread) to other parts of the body.
Currently, the only form of accurately diagnosing melanoma is by a specialist performing a biopsy. This involves the excision of the suspicious mole or lesion in order to fully evaluate the removed tissue in a laboratory. This technique is invasive and as the only defined diagnostic tool for skin cancer, which can result in many unnecessary biopsies being carried out.
Laser: A Potential Non-Invasive Test
Scientists from Lancaster (UK) and Pisa (Italy) Universities may have an alternative non-invasive test – or at the very least, an additional method to detect melanoma: Published in Nature Scientific Reports, using a laser Doppler system, to detect subtle differential blood flow dynamics between malignant (cancerous) and non-malignant moles.
In the study, the laser test required half an hour of recordings of the blood vessels beneath suspicious moles of 55 people. The test combines follow-up biopsies to confirm (100% accuracy) the lasers ability to detect patients with melanoma. Melanoma is associated with rapid blood vessel growth.
One of the head researchers explained: "We used our knowledge of blood flow dynamics to pick up on markers which were consistently different in the blood vessels supplying malignant moles and those beneath normal skin," Stefanovska said in a university news release. The new test "has 100% sensitivity and 90.9% specificity." – meaning the test can confirm negative for melanoma (rule out) in 90.9% of cases, and identify melanoma in 100% of cases it is present!
Doctors welcome this new, promising study but believe further study is required, with a larger population. In addition, recording patient data for half an hour seemed unrealistic for some doctors. However, in time, further development of this technology, as well as larger-scale clinical studies will develop a faster and highly accurate non-invasive technique that could be applied in not only diagnostics, but also screening surveys of the general population.
Once again, HMC stress that people check their skin regularly for any unusual changes or suspicious-looking moles; the acronym ABCDE rule highlights the main features of melanoma to look out for when examining the skin. Any concerns should be reported to a dermatologist – Herzliya Medical Center’s oncology department provides the latest screening, diagnostic tools and treatment of skin cancer, including melanoma.