S Ribero1, G Argenziano2, A Lallas3, E Moscarella4, E Benati4, M Raucci4, S Piana5, C Longo4. 1. Dermatology Department, University of Turin, Turin, Italy. Electronic address: simone.ribero@unito.it. 2. Dermatology Unit, Second University of Naples, Italy; Skin Cancer Unit, Arcispedale S. Maria Nuova-IRCCS, Reggio Emilia, Italy. 3. First Department of Dermatology, Aristotle University, Thessaloniki, Greece. 4. Skin Cancer Unit, Arcispedale S. Maria Nuova-IRCCS, Reggio Emilia, Italy. 5. Pathology Unit, Arcispedale S. Maria Nuova-IRCCS, Reggio Emilia, Italy.
Abstract
BACKGROUND: The latest AJCC classification has included the number of mitoses as a factor for upstaging thin melanomas. Meanwhile, while dermoscopy has often been used to predict melanoma thickness, its value in predicting number of mitoses remains unknown. OBJECTIVE: Our aim is to evaluate the correlation between dermoscopic features and the presence of mitoses in a consecutive cohort of thin melanomas. METHODS: A case control study has been performed to identify specific dermoscopic parameters that could differentiate thin melanomas with 1 or more mitoses per mm2 from those without mitoses. RESULTS: Of 177 melanomas equal to or thinner than 1mm, 131 (74%) lesions had no mitoses and 46 (36%) lesions had at least 1 mitosis×mm2. Dermoscopic features associated with the presence of 1 or more mitoses were the following: peripheral streaks (OR 4.11; 95% CI 1.94-8.71) and black colour (OR 4.70; 95% CI; 2.28-9.68). In contrast, atypical pigment network (OR (0.30; 95% CI 0.15-0.61)) and brown colour (OR 0.36; 95% CI 0.18-0.75) were associated to melanomas without mitoses. The same variables were also associated to the increasing number of mitoses at linear regression. CONCLUSION: Black colour and peripheral streaks can predict the presence of mitoses in thin melanoma, while atypical pigment network and brown colour are associated to thin melanoma without mitoses.
BACKGROUND: The latest AJCC classification has included the number of mitoses as a factor for upstaging thin melanomas. Meanwhile, while dermoscopy has often been used to predict melanoma thickness, its value in predicting number of mitoses remains unknown. OBJECTIVE: Our aim is to evaluate the correlation between dermoscopic features and the presence of mitoses in a consecutive cohort of thin melanomas. METHODS: A case control study has been performed to identify specific dermoscopic parameters that could differentiate thin melanomas with 1 or more mitoses per mm2 from those without mitoses. RESULTS: Of 177 melanomas equal to or thinner than 1mm, 131 (74%) lesions had no mitoses and 46 (36%) lesions had at least 1 mitosis×mm2. Dermoscopic features associated with the presence of 1 or more mitoses were the following: peripheral streaks (OR 4.11; 95% CI 1.94-8.71) and black colour (OR 4.70; 95% CI; 2.28-9.68). In contrast, atypical pigment network (OR (0.30; 95% CI 0.15-0.61)) and brown colour (OR 0.36; 95% CI 0.18-0.75) were associated to melanomas without mitoses. The same variables were also associated to the increasing number of mitoses at linear regression. CONCLUSION: Black colour and peripheral streaks can predict the presence of mitoses in thin melanoma, while atypical pigment network and brown colour are associated to thin melanoma without mitoses.