And dermoscopy for all: Three-point checklist helps non-derms identify, diagnose suspicious lesions

July 1, 2008

A three-point checklist applied in dermoscopy could significantly assist non-experts of dermoscopy to accurately diagnose suspicious skin lesions, according to a recent study.

Key Points

International report - Non-experts in the field of dermoscopy are able to accurately identify and diagnose suspicious lesions, applying a three-point checklist with a dermoscope, according to a recent study.

Researchers demonstrated that the three-point checklist is a valid and reproducible algorithm, with a high sensitivity for the diagnosis of melanoma and pigmented basal cell carcinoma in the hands of non-experts.

Iris Zalaudek, M.D., of the department of dermatology at the Medical University of Graz, Austria, and colleagues came up with a three-point checklist for dermoscopic evaluation, including asymmetry in colors and structures, atypical network and blue-white structures.

Results showed that when making the overall diagnosis based on pattern analysis, experts in dermoscopy had 89.6 percent sensitivity for malignant lesions compared to 69.7 percent sensitivity achieved by the non-experts.

However, when the three non-experts applied the three-point checklist, the sensitivity reached 96.3 percent.

The specificity of the experts using overall diagnosis based on pattern analysis was 94.2 percent compared to 82.8 and 32.8 percent achieved by the non-experts when using overall diagnosis based on pattern analysis and the three-point checklist, respectively.

"In my opinion, the impact of the three-point checklist is rather significant. It is a very simple method that can be used by clinicians from diverse fields of medicine. One does not have to possess a deep, profound knowledge about the workings of the skin or the technique of using a dermoscope, making the three-point checklist method very user-friendly and, at the same time, very effective," Dr. Zalaudek tells Dermatology Times.

Primary care

According to Dr. Zalaudek, the purpose of the three-point checklist as a skin cancer screening test in a primary care setting is simply to help the doctor determine whether a lesion needs to be referred for a more detailed evaluation carried out by a dermatologist.

In other words, "non-dermatologists" will be able to identify skin cancer in the unwary patient and then refer them to a dermatologist or dermatologic surgeon for further management.

Skin cancer is an ever-increasing healthcare problem, and the waiting lists at dermatology offices and screening centers are long.

Dr. Zalaudek says that if general practitioners or family doctors learn to apply this three-point checklist using the dermoscope, they can accurately perform a triage in patients who will need a second expert evaluation.

This naturally helps to reduce the burden of unnecessary consultations for banal lesions in the very busy dermatologic skin screening centers around the world.

"When applying this three-point checklist, the study showed that the non-dermatologists do not misdiagnose suspicious lesions and that they have a very low negative predictive value.

"This means if they diagnose a given lesion as a benign lesion, the chance that the lesion is suspicious or malignant is very low. The misdiagnosis of suspicious lesions occurs in less than 2 percent when the three-point checklist is applied," Dr. Zalaudek says.

Practical applications

She says that this method can educate all non-dermatologists to catch suspicious lesions early, providing a more complete medical care/check-up for their patients.

According to Dr. Zalaudek, research has shown that most patients with the diagnosis of melanoma visited their family doctor, cardiologist or gynecologist at least once in the year before they were diagnosed with this skin cancer.

"This statistic is more than alarming, as skin cancer is clearly visible on the skin and it simply takes a trained eye and a bit of experience to simply see it.

"In most cases, melanoma is usually not a quickly growing tumor, especially superficial spreading melanoma, and one can assume that these patients already had their melanoma since the previous year. Their physician simply did not identify it properly," Dr. Zalaudek says.

She says that in a way, the dermoscope forces the physician to go closer to the patient and not look at the skin from a distance of 2 to 3 meters.

This clearly aids in the detection of suspicious lesions, and at the same time is also appreciated by the patient, who feels that the physician takes serious care of his or her problem.

Generally, it will take one to two minutes longer to screen all the moles of a patient with dermoscopy, and with this three-point checklist, non-dermatologist physicians can now screen their patients much more effectively, Dr. Zalaudek says.