Statistical evaluation of dermoscopic features in basal cell carcinomas.

BACKGROUND

Early detection of basal cell carcinoma (BCC) is of crucial importance, as serious morbidity may result from undiagnosed tumor.

OBJECTIVE

To evaluate diagnostic significance (specificity, sensitivity, positive and negative predictive value) of dermoscopic features in BCCs.

METHODS

A prospective observational study was conducted using contact polarized dermoscopy to evaluate the presence of various dermoscopic features. Images were evaluated for a range of dermoscopic colors, structures, and vessels.

SETTING

Specialized University Clinic.

PATIENTS: A sample of 151 histopathologically verified BCCs was collected from 116 patients (64 males and 52 females). The populations included predominantly Caucasian individuals.

MAIN OUTCOME MEASURES: The sensitivity, specificity, positive and negative predictive values of the various dermoscopic features seen in BCCs were calculated according to standard formulas.

RESULTS

The highest diagnostic value (specificity [Sp] = 100%, positive predictive value [PPV] = 100%) for BCC had spoke-wheel areas, short fine telangiectasias, white rosette, annular hypopigmentation, multiple erosions, and ulceration. Arborizing vessels (Sp = 96%, PPV = 98%) and microvessels (Sp = 93%, PPV = 97%) had significant diagnostic value for BCC. Annular distribution of telangiectatic vessels (Sp = 96%), translucency (Sp = 93%), and multiple blue-gray globules (Sp = 89%) had the same PPV of 95% for BCCs. Other dermoscopic features of this study are not strongly associated with the diagnosis of BCC.

CONCLUSION

Dermoscopic features relevant for diagnosis of BCC have different diagnostic "weight." Clinicians should have known the sensitivity and specificity of each relevant feature before they can make an accurate dermoscopic diagnosis of BCC.