Melanocytic or Not? Dermoscopy and Reflectance Confocal Microscopy for Lesions Difficult to Diagnose: A Cross-Sectional Diagnostic Accuracy Study

Background: Different techniques for non-invasive skin examination and early diagnosis of skin lesions are available nowadays, being dermoscopy and reflectance confocal microscopy (RCM) the most diffused ones. Several studies supported the complementary use of dermoscopy and RCM that improves diagnostic accuracy when dealing with melanocytic lesions. Objectives: To analyze RCM diagnostic accuracy in the differential diagnosis between melanocytic and non-melanocytic lesions. Methods: This is a cohort selected cross-sectional study conducted at the Dermatology Unit of the University of Campania L. Vanvitelli, Naples, Italy, from 2012 to 2020. We searched the image database for all excised lesions for which the clinical and dermatoscopic differential diagnosis was between melanocytic and non-melanocytic and for which an RCM examination was performed. Sensitivity, specificity, and diagnostic accuracy values ​​were estimated. Results: The study included 53 cases that were found to have disagreement between clinical, histological and RCM diagnosis, of which, in 31 cases the differential diagnosis was melanocytic vs non-melanocytic lesion. The RCM reached a specificity of 87% (95% CI: 0.73-1) and a sensitivity of 62.5% (95% CI: 0.29-0.96) in the present sample. Diagnostic accuracy was 80.6% (95% CI: 0.67-0.94). Conclusion: RCM has a high specificity in differentiating between difficult-to-diagnose melanocytic and non-melanocytic lesions.

Segmentation of Melanocytic Lesion Images Using Gamma Correction with Clustering of Keypoint Descriptors

The early detection of skin cancer, especially through the examination of lesions with malignant characteristics, has been reported to significantly decrease the potential fatalities. Segmentation of the regions that contain the actual lesions is one of the most widely used steps for achieving an automated diagnostic process of skin lesions. However, accurate segmentation of skin lesions has proven to be a challenging task in medical imaging because of the intrinsic factors such as the existence of undesirable artifacts and the complexity surrounding the seamless acquisition of lesion images. In this paper, we have introduced a novel algorithm based on gamma correction with clustering of keypoint descriptors for accurate segmentation of lesion areas in dermoscopy images. The algorithm was tested on dermoscopy images acquired from the publicly available dataset of Pedro Hispano hospital to achieve compelling equidistant sensitivity, specificity, and accuracy scores of 87.29%, 99.54%, and 96.02%, respectively. Moreover, the validation of the algorithm on a subset of heavily noised skin lesion images collected from the public dataset of International Skin Imaging Collaboration has yielded the equidistant sensitivity, specificity, and accuracy scores of 80.59%, 100.00%, and 94.98%, respectively. The performance results are propitious when compared to those obtained with existing modern algorithms using the same standard benchmark datasets and performance evaluation indices.

Three Years Retrospective Study of Melanocytic Lesion in Tertiary Hospital: Comparing Benign & Malignant Data

Melanocytic lesion is defined as skin symptom due to proliferation of melanocytes. It may be considered benign, commonly diagnosed as melanocytic nevus (MN), or may also be malignant as malignant melanoma (MM). Publication of epidemiologic data about melanocytic lesion in Indonesia is limited. The aim of this study was to evaluate the epidemiologic findings of melanocytic lesion based on histopathology and clinical data. This descriptive study was done by collecting retrospective pigmented lesion from histopathology database at Department of Anatomical Pathology dr. Cipto Mangunkusumo National Hospital from 2014 - 2017. Retrieved data were analyzed descriptively for MN and MM include clinical diagnosis, age, sex, location, size and clinical working diagnosis. There were 121 cases of melanocytic lesions consisting of 87.6% MN. Females were more frequent for benign lesions. MN cases were mostly seen at the age below the fourth decade, while from 12 cases of MM found above fourth decade. MN was located mostly on the head and neck, while MM mostly in the lower extremities and soles. There were 75 lesions size and 4 lesions location were unknown data missing. MM is still considered rare. Completing clinical finding in the histopathology request form by surgeons will aid in defining better characteristic of melanocytic lesion in our population. Keyword: epidemiology, melanocytic lesion, nevus melanocytic, malignant melanoma. Studi Retrospektif Lesi Melanositik dalam Tiga Tahun di RS Tersier: Perbandingan Data Jinak dan Ganas Abstrak Lesi melanositik didefinisikan sebagai lesi kulit akibat proliferasi melanosit. Lesi melanositik dapat dianggap jinak, umumnya didiagnosis sebagai nevus melanositik (NM), atau merupakan ganas yaitu melanoma maligna (MM). Publikasi data epidemiologi tentang lesi melanositik di Indonesia masih terbatas. Tujuan dari penelitian ini adalah untuk melakukan evaluasi gambaran epidemiologis lesi melanositik berdasarkan data histopatologi dan klinis. Penelitian deskriptif ini dilakukan dengan mengumpulkan data retrospektif lesi berpigmen dari basis data histopatologi di Departemen Patologi Anatomi Rumah Sakit Nasional dr. Cipto Mangunkusumo dari tahun 2014 - 2017. Data dianalisis secara deskriptif untuk NM dan MM termasuk diagnosis kerja, usia, jenis kelamin, lokasi, ukuran, dan diagnosis klinis. Terdapat 121 kasus lesi melanositik yang terdiri atas 87,6% NM. Lesi jinak lebih banyak ditemukan pada wanita. Terdapat 75 dan 4 kasus dengan data ukuran lesi dan lokasi tidak tercantum. MM masih dianggap jarang. Kasus NM sebagian besar terlihat pada usia di bawah dekade keempat, sedangkan dari 12 kasus MM di atas dekade keempat. NM sebagian besar terletak di kepala dan leher, sedangkan MM ditemukan di ekstremitas bawah dan telapak kaki. Melengkapi temuan klinis dalam formulir permintaan histopatologi oleh dokter bedah akan membantu dalam menentukan karakteristik lesi melanositik lebih baik pada populasi ini. Kata kunci: epidemiologi, lesi melanositik, nevus melanositik, melanoma maligna

Congenital Melanocytic Nevus and Fibroepithelioma of Pinkus: A Rare Type of Collision Tumor

Congenital melanocytic nevus is benign pigmented lesion of the skin usually present at birth. Here we report a case of 61-year-old male who presented with a pigmented lesion on the trunk, which on biopsy showed features of both congenital melanocytic nevus and fibroepithelioma of Pinkus. We reviewed literature for this combination and found only one case reported so far. Hence, it seems that it is very unusual to seefibroepithelioma of Pinkus in conjunction with a melanocytic lesion.

Discordance in Diagnosis of Melanocytic Lesions and Its Impact on Clinical Management

Context.— Accurate diagnosis of melanocytic lesions is fundamental for appropriate clinical management. Objective.— To evaluate the degree of discordance, if any, between histopathologic diagnoses of melanocytic lesions at referring institutions and at a tertiary referral cancer center and the potential impact of such discordance on clinical management. Design.— We retrospectively identified all patients referred to our comprehensive cancer center for evaluation of a melanocytic lesion from January 2010 to January 2011. For each patient, the histopathologic diagnosis from the referring institution was compared with the histopathologic diagnosis from a dermatopathologist at our center. Discordances were classified as major if they resulted in a change in clinical management and minor if they did not. Results.— A total of 1521 cases were included. The concordance rates were 72.2% (52 of 72) for dysplastic nevus, 75.0% (15 of 20) for all other types of nevi, 91.1% (143 of 157) for melanoma in situ, 96.1% (758 of 789) for invasive melanoma, and 99.6% (478 of 480) for metastatic melanoma. Major discordances were found in 20.2% of cases (307 of 1521), and minor discordances were found in 48.8% of cases (742 of 1521). Compared with the guideline-based treatment recommendation based on the referring-institution diagnosis, the guideline-based treatment recommendation based on the cancer center diagnosis was more extensive in 5.9% (89 of 1521) of patients and less extensive in 5.0% (76 of 1521) of patients. Conclusions.— Our findings underscore the importance of secondary histopathologic review of melanocytic lesions by expert dermatopathologists because significant changes in the diagnosis, tumor classification, and/or staging may be identified; thus, resulting in critical changes in recommendations for clinical management.