Accuracy of dermatoscopy for the diagnosis of nonpigmented cancers of the skin

Christoph Sinz, Philipp Tschandl, Cliff Rosendahl, Bengu Nisa Akay, Giuseppe Argenziano, Andreas Blum, Ralph P. Braun, Horacio Cabo, Jean-Yves Gourhant, Juergen Kreusch, Aimilios Lallas, Jan Lapins, Ashfaq A. Marghoob, Scott W. Menzies, John Paoli, Harold S. Rabinovitz, Christoph Rinner, Alon Scope, H. Peter Soyer, Luc Thomas, Iris Zalaudek, Harald Kittler

Nonpigmented skin cancer is common, and diagnosis with the unaided eye is error prone. To investigate whether dermatoscopy improves the diagnostic accuracy for nonpigmented (amelanotic) cutaneous neoplasms. We collected a sample of 2072 benign and malignant neoplastic lesions and inflammatory conditions and presented close-up images taken with and without dermatoscopy to 95 examiners with different levels of experience. The area under the curve was significantly higher with than without dermatoscopy (0.68 vs 0.64, P < .001). Among 51 possible diagnoses, the correct diagnosis was selected in 33.1% of cases with and 26.4% of cases without dermatoscopy (P < .001). For experts, the frequencies of correct specific diagnoses of a malignant lesion improved from 40.2% without to 51.3% with dermatoscopy. For all malignant neoplasms combined, the frequencies of appropriate management strategies increased from 78.1% without to 82.5% with dermatoscopy. The study deviated from a real-life clinical setting and was potentially affected by verification and selection bias. Dermatoscopy improves the diagnosis and management of nonpigmented skin cancer and should be used as an adjunct to examination with the unaided eye.