Clinical selection of melanocytic lesions for dermoscopy decreases the identification of suspicious lesions in comparison with dermoscopy without clinical preselection

Background: In most cases dermoscopy is performed only on lesions selected by clinical inspection which present worrying clinical features or appear to deviate from the patient's average type of naevus. Thus, possible early malignant melanomas (MMs) or MM precursors, lacking typical clinical characteristics, may elude the dermoscopic examination. Objectives: To perform a comparison between two different approaches to the patient's examination, one based on a clinical preselection of lesions to be examined by dermoscopy, and the other consisting of the dermoscopic scrutiny of all melanocytic lesions with a diameter ≥2 mm (total dermoscopy). Methods: Sixty-three consecutive patients with MM, undergoing periodic dermoscopic examinations of their naevi, were enrolled in the study. The patients first underwent an assessment of the entire skin with the unaided eye for the identification of lesions for dermoscopy. Subsequently, the patients underwent dermoscopic examination of all melanocytic lesions. Images of naevi identified by clinical examination or by total dermoscopy as having dermoscopic aspects characteristic of a suspicious lesion, i.e. necessitating either surgical excision or follow-up examinations, were separately recorded, classified and described employing the ABCD rule of dermoscopy and the seven-point checklist. Results: Five hundred and fifty-one lesions were chosen by clinical inspection for subsequent dermoscopic examination; among these, 117 were considered for excision or follow-up. Ninety-two further lesions were identified for excision or follow-up by employing only total dermoscopy. Dermoscopy scores of lesions selected by clinical inspection plus dermoscopy were similar to those identified by dermoscopy alone. In the former group, 13 lesions showed either an ABCD or a seven-point score corresponding to a suspicious lesion, whereas eight such lesions were identified only by total dermoscopy. Thus, by clinical selection plus dermoscopy we were able to identify only 62% of dermoscopically suspicious lesions. Conclusions: Clinical selection of melanocytic lesions for dermoscopic examination is associated with the 'loss' of a conspicuous number of lesions which deserve surgical excision or follow-up examinations. Total dermoscopy, enabling the detection of suspicious lesions, together with storage, retrieval and sequential comparison of their images, could enhance MM diagnosis by follow-up, in comparison with clinical preselection for dermoscopy. © 2006 British Association of Dermatologists.