New Melanoma Identification Device Narrowly Apporoved by FDA Panel
Posted Nov 19 2010 12:00am
MelaFind, a device designed for use by dermatologists for in-vivo detection of suspicious pigmented skin lesions, has been narrowly approved by an FDA advisory panel. Here is an excerpt from the article (see: Panel Splits over Skin Cancer Detection Device )
An FDA advisory panel has voted 8-7, with one member abstaining, to recommend approval for an experimental skin cancer detection system called MelaFind. A vote so close generally is not considered an endorsement in the eyes of FDA officials, who have the final say in whether to approve the device. The FDA does not have to follow the advice of its advisory committees, but it often does. Some panelists on the [committee] were concerned that relying on a device to detect melanoma could lead to unnecessary biopsies, or worse: missed skin cancers. Those who voted against the device also were concerned that non-dermatologist physicians might start using it. "I have a problem with this," said panelist Lynn Drake, MD, a dermatologist at Massachusetts General Hospital and a lecturer at Harvard, who voted against approval. "This disease kills people. I think we need to be very careful about approving something that might replace a human's judgment." But other panelists felt that even though the device proved only slightly superior at detecting melanoma in suspicious lesions than a physician alone, having another tool to aid in skin cancer detection would ultimately benefit patients....The noninvasive device uses a dermascope with near-infrared light to image the skin through a thin layer of alcohol or oil while a digital camera captures images of the lesion. A computer connected to the dermascope displays the image on a screen in the physician's office. Software sorts out various patterns and analyzes lesion color, shape, and consistency to assign a risk that a lesion is a melanoma.MELA Sciences , the device's manufacturer, says MelaFind can visualize lesion structures under the skin.
This news item interested me for a few reasons. First of all, MetaFind is an example of in-vivo imaging technology that, at some time in the future, may replace the pathologist and histopathology in the diagnosis of various types of lesions. Other examples of such technology include molecular imaging (see: The Role of Molecular Imaging Versus Histopathology in Diagnosis ) and in-vivo endoscopic imaging. Neither of these two technologies will replace the pathologist soon but it's not hard to see a trend here.
Two of the objections to the product by the panel members, quoted in the article, also caught my attention. One is the "guild defense" argument cited by a dermatologist that non-dermatologists might start using the device and thus take away work from specialists. In my opinion, this can't happen fast enough. I believe that much of the initial triage of patients during office visits should be managed by specially trained nurses. It would be an advantage for all of us if initial skin-checks could be accomplished by such nurses using a product like MelaFind. A dermatologist can be brought into the room, when necessary, at the end of the visit to confirm the clinical findings. This would be a very efficient way to address the current epidemic of melanomas.
Secondly, I was struck by the objection of one of the panel members that a downside of the device was that technology will "replace human judgement." In my opinion, only poorly-designed technology poses such a risk. Well-designed technology should always improve human performance but will provide an option to override the technology if and when human judgement is superior. This is the case when using computer algorithms to quantify tissue biomarkers in digital pathology. However and in such instances, the human operator needs to have a strong rationale for the override. After all, human expertise is used to develop the computer algorithms and the intelligence of the current operator may be superior to that which was used to develop the algorithms (see: In-Vitro Biomarkers vs. In-Situ Biomarkers ). Moreover, the algorithms may also not be working properly or inadequately designed.