The Clinical Research Of Dermoscopy In The Diagnosis Of Acral Melanocytic Nevi And Acral Lentiginous Melanoma

Objective:Acral lentiginous melanoma(ALM)is the most common type of cutaneous melanoma in Chinese and the acral melanocytic nevi(AMN)also have a high incidence rate.The lesions of ALM are hard to be differentiated from AMN because of the lack of typical features of melanoma in early stage,leading to the misdiagnosis or missed diagnosis,resulting in the opportunity missing in ALM or overtreatment in AMN.Dermoscopy is a noninvasive tool that can improve the accuracy of diagnosing melanoma and other pigmented lesions.Our study aimed to evaluate the value of dermoscopy in diagnosing and differential diagnosing acral melanocytic lesions and to explore the sensitivity and specificity of dermoscopy in the diagnosis of ALM,and then analyze the specific dermoscopic features of ALM and AMN and compared them with foreign studies.Methods:84 patients who were diagnosed for acquired acral melanocytic skin lesions in our clinic from October 2015 to January 2018 were enrolled in this study,with all the lesions were located in palms,soles and the palm side of fingers and toes,and the patients' age,gender,occupation,medical history and the lesion area are unlimited.All the lesions were examined by dermoscopy and histopathology,and saved clinical and dermoscopic pictures of cases.Then the experienced clinical doctors made a diagnosis according to the pictures and described their dermoscopic features.Again with the histopathological diagnosis as the gold standard,we calculated the sensitivity,specificity,Youden index and Kappa value,and analyzed the consistence of dermoscopic and pathological diagnosis,at the same time,to calculate the incidence of each dermoscopic features of AMM and ALM and compared with the results of foreign studies.Results:1.In 84 patients,70 patients were diagnosed AMN and 14 cases were diagnosed ALM according to clinical and dermoscopic features.And 68 patients were diagnosed AMN(20 males ans 48 females,5 lesions on palms and 63 lesions on soles)and 16 cases were diagnosed ALM(9 males and 7 females,16 lesions on soles)according to pathological findings.2.The sensitivity,specificity,Youden index and Kappa value of dermoscopic diagnose for AMN were 91.2%,81.2%,72.4%and 0.676,which means dermoscopic and pathological diagnosis for AMN were consistent.3.The sensitivity,specificity,Youden index and Kappa value of dermosopic diagnose for ALM were 81.2%,91.2%,72.4%and 0.676,which means dermoscopic and pathological diagnosis for ALM were consistent.4.Among AMN,the most common pattern was the parallel furrow(38.2%),followed by fibrillar(26.5%)and globular(16.2%).While among ALM,the most common pattern was the parallel ridge(81.25%),followed by(68.75%)and multicomponent pattern(62.5%).Conclusions:1.AMN occurred in females mainly and there were no differences in gender in ALM.And the sole was the most frequent location both of AMN and ALM.2.The sensitivity and specificity of dermoscopy in the diagnosis of AMN and ALM were higher,and dermoscopic and pathological diagnosis for both AMN and ALM were consistent.3.There are special dermoscopic patterns both in AMN and ALM,which can distinguish them from other acral pigmented skin lesions.4.The dermoscopic patterns in AMN and ALM in our study are in accord with foreign research as a whole,but there are also some little difference that need another study with more cases and wider territories.