A descriptive observational study on clinical and dermoscopic features of benign melanocytic neoplasms.

BACKGROUND: Benign melanocytic neoplasms have nests of melanocytic cells and show characteristic dermoscopic features. Clinical and dermoscopic features have not been studied previously in the Indian population. AIMS: To study the clinical, epidemiological and dermoscopic patterns of benign melanocytic neoplasms. METHODS: This was a descriptive, observational, single centre study. In 107 patients with melanocytic neoplasms, 167 lesions were clinically examined and studied under the dermoscope and histopathological examination was done when indicated. The lesions were broadly divided as acquired and congenital. Five main dermoscopic patterns were seen-globular, homogenous, reticular, parallel and streaks. If there were two of these patterns in a particular lesion, it was termed 'mixed pattern'. The presence of three or more patterns was called 'multicomponent pattern'. Various other features were also observed. RESULTS: The majority of patients belonged to the third decade with a female preponderance. History of increased UV exposure and family history was significant in acquired nevi. The dermoscopic pattern progressed from predominantly reticular in junctional nevi to predominantly globular in compound nevi and lesser pigment in intradermal nevi, with more vascular structures. The congenital melanocytic nevi showed additional features of comedo- like lesions, milia- like cysts, perifollicular pigmentary changes and increased colour variation. Even though colour variation was observed in both acquired and congenital lesions, no signs of dysplasia were seen on histopathology. LIMITATIONS: A larger sample size is required, with follow up of lesions. No parallel studies in brown skinned population were found for exact comparison. CONCLUSION: Benign melanocytic proliferations are often neglected in our country. This study will help in understanding the course, clinical features and dermoscopic patterns of various benign melanocytic neoplasms, and will be a step forward towards research in our population. To the best of our knowledge, this is the first study of its kind in India.

Utility of high-frequency ultrasonography in the diagnosis of benign and malignant skin tumors.

Various benign and malignant tumors may arise from the skin. These may be of epidermal, dermal, subcutaneous or appendageal origin. Skin biopsy is the gold standard for diagnosis of skin tumors. There is paucity of published data on the role of imaging modalities in diagnosis of skin tumors. High-frequency ultrasonography (7-50 MHz) is a potential non-invasive, objective modality which can be utilized in the diagnosis and localization of skin tumors. It provides valuable information about the tumor characteristics such as size, shape, depth, consistency and vascularity before invasive skin biopsy or surgery is planned. Sentinel lymph nodes in malignant melanoma can be well visualized and studied by this technique. It is also a good modality to detect local recurrence of tumors during post-operative follow up, especially those with a high likelihood of local recurrence or lesions excised with inadequate margins. High-frequency ultrasonography is additive to clinical diagnosis and can be considered a useful non-invasive method to plan the management of various skin tumors and is of prognostic value in some cases.