Dermoscopy, the use of a handheld instrument to magnify the skin 10-fold while providing a light source, is a quick, useful, cost-effective tool for detecting melanoma in family medicine.1-4 The device, which allows the physician to visualize structures below the stratum corneum that are not routinely discernible with the naked eye, can be attached to a smartphone so that photos can be taken and reviewed with the patient. The photo can also be reviewed after a biopsy result is obtained.
Its use among non-dermatologist US physicians appears to be relatively low, but rising. One small study of physicians working in family medicine, internal medicine, and plastic surgery found that only 15% had ever used a dermatoscope and 6% were currently using one.5
As a family physician, you can expand your diagnostic abilities in dermatology with the acquisition of a dermatoscope (FIGURE 1) and some time invested in learning to interpret visible patterns. With that in mind, this review focuses on the diagnosis of skin cancers and benign growths using dermoscopy. We begin with a brief look at the research on dermoscopy and how it is performed. From there, we’ll detail an algorithm to guide dermoscopic analysis. And to round things out, we provide guidance that will help you to get started. (See “Choosing a dermatoscope—and making the most of it,” and “To learn more about dermoscopy …”.)
Choosing a dermatoscope—and making the most of it
1. Consider acquiring a hybrid dermatoscope.
Nonpolarized dermatoscopes (NPDs) and polarized dermatoscopes (PDs) provide different but complementary information. PDs enable users to identify features such as vessels and shiny white structures that are highly indicative of skin cancer. Because PDs are highly sensitive for detecting skin cancer and do not require a liquid interface or direct skin contact, they are the ideal dermatoscopes to use for skin cancer screening.
However, maintaining the highest specificity requires the complementary use of NPDs, which are better at identifying surface structures seen in seborrheic keratoses and other benign lesions. Thus, if the aim is to maintain the highest diagnostic accuracy for all types of lesions, then the preferred dermatoscope is a hybrid that permits the user to toggle between polarized and nonpolarized features in one device.
2. Choose a dermatoscope that attaches to your smartphone and/or camera.
This helps you capture digital dermoscopic images that can be analyzed on a larger screen, which permits:
- enlarging certain areas for in-depth analysis of structures and patterns
- sharing the image with the patient to explain why a biopsy is, or isn’t, needed
- sharing the image with a colleague for the purpose of a consult or a referral, or using the images for teaching purposes
- saving the images in order to follow lesions over time when monitoring is indicated
- ongoing learning. After each biopsy result comes back, we recommend correlating the dermoscopic images with the biopsy report. If your suspected diagnosis was correct, this reinforces your knowledge. If the pathology diagnosis is unexpected, you can learn by revisiting the original images to look for structures or patterns you may have missed upon first examination. You may even question the pathology report based on the dermoscopy, prompting a call to the pathologist.
- keeping a safe distance from the patient when looking for scabies mites.
To learn more about dermoscopy…
Dermoscopy 2-Step Algorithm. Available for free on iTunes, Google Play, and at www.usatinemedia.com, this free app (developed by 3 of the 4 authors) is intended to help you interpret the dermoscopic patterns seen with your dermatoscope. It asks a series of questions that lead you to the most probable diagnosis. The app also contains more than 80 photos and charts to help you with your diagnosis. No Internet connection is needed to view the full app. There are 50 interactive cases to solve.
YOUdermoscopy Training (Available for free on iTunes, Google Play, and at https://www.youdermoscopytraining.org/) offers a fun game interface to test and expand your dermoscopy skills.
OTHER INTERNET RESOURCES:
- Dermoscopedia provides state-of-the-art information on dermoscopy. It’s available at: https://dermoscopedia.org.
- A free dermoscopy tutorial is available at: http://www.dermoscopy.org/
- The International Dermoscopy Society’s Web site, which offers various tutorials and other information, can be found at: http://www.dermoscopy-ids.org/.
Dermoscopy courses are a great way to get started and/or to advance your skills. The following courses are taught by the authors of this article:
- The American Dermoscopy Meeting is held yearly in the summer in a national park. See http://www.americandermoscopy.com/.
- Memorial Sloan Kettering Cancer Center holds a yearly dermoscopy workshop each fall in New York City. See http://www.mskcc.org/events/.
- The yearly American Academy of Family Physicians' FMX meeting offers dermoscopy workshops. See https://www.aafp.org/events/fmx.html.
Continue to: What the research says