New Technologies Detect Deadly Melanoma In Early Stages
The incidence of melanoma, the deadliest form of skin cancer, has been increasing at alarming rates, leading cancer experts to wonder if this represents an actual epidemic or is the result of more widespread screenings, which lead to more and earlier diagnoses. A new study implies that it is the former — melanoma rates may indeed be escalating. The good news is that easier, more effective new screening technologies are not far behind.
For the study, a research team led by Eleni Linos, MD, DrPH, at Stanford University Medical Center analyzed more than 70,000 invasive melanoma cases diagnosed between 1992 and 2004 from the Surveillance, Epidemiology and End Results (SEER) program. The researchers explored incidence and mortality rates three ways — by histological types, thickness of tumors and socioeconomic group. If rising incidence was linked to screenings, they reasoned, there would be a smaller increase for lower socioeconomic groups who have less access to such medical care. The researchers found that melanomas increased at a rate of 3.1% per year for all histological subtypes and thicknesses and that the incidence rates of melanoma doubled in all socioeconomic groups over a 10-year period. This suggests that the rising rates of melanoma are very real. The study was published in the January 8, 2009, online issue of the Journal of Investigative Dermatology.
According to the American Cancer Society, more than one million new cases of skin cancer occur annually. Melanoma is the most virulent form of skin cancer, resulting in 75% of all skin cancer deaths, but it’s curable if detected early. The five-year survival rate for people whose melanomas are detected and treated before they spread to the lymph nodes and other parts of the body is 99%.
NEW TECHNOLOGICAL ADVANCES IN EARLY DETECTION METHODS
Until recently, dermatologists had few tools beyond clinical examination to detect suspicious lesions — which often caused missed diagnoses as well as painful biopsies that proved unnecessary. Now there are new, non-invasive diagnostic tools that help dermatologists find melanoma and other skin cancers earlier, when they are most treatable. “Detecting skin cancer in its earliest stages ultimately saves lives,” said Ellen Marmur, MD, chief, Division of Dermatologic and Cosmetic Surgery and assistant clinical professor at The Mount Sinai Medical Center in New York City. “These new devices lead us to do a biopsy when we may not have thought one was necessary — and also allow us to see benign features which stop us from doing unnecessary biopsies, too.”
The hand-held dermascope magnifies polarized light, enabling dermatologists to see the depth and pattern of skin pigmentation (such as red or brown background colors) so they can detect lesions that may be cancerous. “The dermascope is a fantastic tool,” said Dr. Marmur. “If someone walks into my office with 100 scary spots on his skin, I don’t want to biopsy all of them, so I use the dermascope to evaluate which ones are most likely to be dangerous and should be biopsied.”
The VivaScope (Lucid, Inc.) is a confocal microscope with which physicians can visualize the actual cells of a skin lesion to determine whether it is cancerous. The newest version, the VivaScope 3000, is a lightweight, hand-held device that can be used in hard-to-access places on the body such as the corner of the nose, tips of ears or between toes and fingers. Doctors can also share images with pathologists via a manufacturer-sponsored secure Internet site. The VivaScope is expensive and is mostly found at university medical centers.
Hand-Held Imaging Devices and Computer Software
The MelaFind (Electro-Optical Sciences, Inc.) is a type of dermascope that employs light wavelengths to capture thousands of characteristics of a skin lesion, then uses a computer algorithm to determine the degree of risk. “The computer grades the lesion according to certain features, and if the score is high enough on the risk scale, it will recommend a biopsy,” explained Dr. Marmur. Also very expensive, the MelaFind is still undergoing clinical trials, so is not yet widely available.
Total-Body Photography to Map Moles
Total-body photography is used for mole mapping, which uses digital photography to monitor the size and shape of moles, comparing past and present images to find changes that warrant further evaluation. It is valuable as an objective tool to compare changes in moles, notes Dr. Marmur, adding that new digital technology is bringing continued improvement.
Epidermal Genetic Information Retrieval (Tape Stripping)
Epidermal Genetic Information Retrieval (EGIR), otherwise known as tape stripping, uses adhesive tape to pick up genetic material from the top layer of the skin so it can be analyzed for the presence of key markers that indicate early-stage melanoma. As with other technologies, lesions are then analyzed and classified by computer to determine whether a biopsy is needed. Dr. Marmur calls it an “unbelievably exciting innovation.” EGIR (from DermTech) is currently in clinical studies.
Diagnosis by Scent
Skin cancers may one day be detected by scent. Researchers at the Monell Chemical Senses Center in Philadelphia have measured compounds in the air above a skin lesion that can identify basal cell carcinoma. These promising results may lead to the ability to detect other forms of skin cancer, such as squamous cell carcinoma and melanoma, and the development of mechanical sensors that can identify these compounds, possibly in very early stages.
THE ART OF MEDICINE
While these innovative new tools are quite promising, dermatologists must still call upon their experience in the art of medicine, otherwise known as doctor’s intuition. “Ultimately, we will still listen to the patient, rely on the physical examination, and go with our own judgment,” said Dr. Marmur. “We see these spots on the skin of patients every day and we’re constantly comparing them to other spots, so if we sense that a mole is dangerous even if the tape strip says it’s normal, we must still have the courage to go ahead and biopsy it.”
TIPS FOR REDUCING SKIN CANCER RISK
To reduce your risk for skin cancer, Dr. Marmur advises “healthy habits from a young age: good nutrition, good sun protection, good athletic fitness and no smoking, because smoking increases your risk of skin cancer.”
Remember to go for annual dermatology checkups, and keep in mind the ABCDs — and now Es — that characterize suspicious moles:
- Asymmetry — one half unlike the other half;
- Border — irregular, ragged, notched or poorly defined;
- Color — varies from one area to another… shades of tan and brown, black, sometimes white, pink, red or blue;
- Diameter — the size of a pencil eraser or larger; and
- Elevation — a mole or skin lesion raised above the skin and/or has an uneven surface. If a mole exhibits any of these characteristics, it should be brought to a dermatologist’s attention.