SkinCancerNet Article
Melanoma Diagnosis Requires Biopsy

There seems to be some confusion about how dermatologists can diagnose melanoma, the most serious form of skin cancer. To set the record straight, studies are looking at how to diagnose melanoma without a biopsy and researchers are making progress. It is, however, not yet possible to tell if a patient has melanoma or any type of skin cancer without a biopsy.

What New Tools Can Do
Part of this confusion may come from the technological advances that have given dermatologists new tools and methods for examining the skin. Designed to give dermatologists a better view, these tools can help dermatologists decide whether a lesion should be biopsied. None of these tools can tell the dermatologist if a suspicious lesion is skin cancer. At least, not yet.

The dermatoscope is the most widely used of these devices. Dermatologists use this handheld device to magnify and illuminate lesions that could be melanoma. A magnified view helps dermatologists determine if a lesion suspected of being a melanoma should be biopsied. This, in turn, improves detection of melanoma and reduces the need for unnecessary biopsies. It does not eliminate the need for a biopsy

One device that has been making headlines is called the confocal scanning laser microscope. It may be referred to as CSLM (and sometimes CLSM or LSCM). This device directs a low-power laser beam onto the skin. As the beam hits the skin, a series of views are collected, assembled, and evaluated using specialized software. The resulting information gives the dermatologist a better view of what is happening.

Collecting this information can help dermatologists detect lesions that could be skin cancer. This tool cannot tell if a suspicious lesion is skin cancer. Only a biopsy can do that, but the tool can help the dermatologist evaluate suspicious lesions and decide if the lesion should be biopsied. This device is not yet widely available.

One type of confocal microscopy that you may have heard about is reflectance confocal microscopy (RCM). This novel imaging technique uses a low-power laser beam to scan the skin and produce a highly detailed image of a suspicious lesion, giving the dermatologists an almost cellular view. In studies, dermatologists have been able to find actinic keratoses (AKs), basal cell carcinomas, and melanomas before the biopsy confirmed the finding. RCM holds much promise as a non-invasive technique, but more research is needed.

Two other imaging techniques that are being investigated are optical coherence tomography (OCT) and reflex transmission imaging (RTI). OCT is routinely used to examine lesions on the eye. Its helpfulness in looking at lesions on the skin has not been fully studied. RTI is a type of ultrasound. Its future as a useful tool for detecting melanoma is not clear. More studies are needed.

While these devices and techniques cannot diagnose skin cancer, they give dermatologists a closer look at suspicious skin lesions. This, in turn, can help dermatologists find suspicious lesions earlier than before and better determine whether a biopsy is needed. None of these devices can confirm that a suspicious lesion is skin cancer. Only a biopsy can tell us for sure. At least for now.

References:
Casagrande Tavoloni Braga J, Scope A, Klaz I et al. “The significance of reflectance confocal microscopy in the assessment of solitary pink skin lesions.” Journal of the American Academy of Dermatology 2009. [article in press]

Goodson AG, Grossman D. “Strategies for early melanoma detection: Approaches to the patient with nevi.” Journal of the American Academy of Dermatology 2009; 60: 719-35; quiz 36-8.

Segura S, Puig S, Carrera C et al. “Development of a two-step method for the diagnosis of melanoma by reflectance confocal microscopy.” Journal of the American Academy of Dermatology 2009. [article in press]

All content solely developed by the American Academy of Dermatology