A multicentric study on dermoscopic patterns and clinical-dermoscopic-histological correlates of basal cell carcinoma in Indian skin.

Background: Literature on the dermoscopic patterns of basal cell carcinoma (BCC) in India is limited.

Aim: To describe the dermoscopic pattern and dermoscopic-histopathological correlation in a large cohort of patients with BCC from India, with a particular focus on skin of colour (SOC).

Methods: This retrospective study was conducted under the aegis of the Dermatoscopy Society of India. Clinical details were collected, and two lead authors independently analysed dermoscopic images of BCC for a predefined set of characteristics. Histopathological slides/blocks were reviewed, and dermoscopic-histological correlation attempted.

Results: In total, 143 patients with BCC and skin phototypes IV-VI were included. The mean largest BCC diameter was 3.10 ± 3.68 cm and there was a significant but weak association between duration and largest dimension of the lesion (Spearman ρ = 0.33, P < 0.01). Nearly half of the cases were diagnosed with pigmented BCC and the most common histological subtype was nodular BCC (37.9%). Dermoscopically, blue-grey dots and arborizing vessels were the most common features (60.0%). Pigmentary changes were found in the majority of cases, and included blue-white veil, blue-grey ovoid nests and maple leaf-like areas. A third of our patients had short linear telangiectasia, polymorphic vessels and regular dotted vessels, and another third exhibited a dermoscopic rainbow effect. Arborizing vessels were significantly more common with micronodular (78.9%) and nodular variants (74.1%, P = 0.05), whereas regular dotted vessels (68.4%, P = 0.04), blue-white veil (84.2%, P = 0.02) were significantly associated with micronodular variant.

Conclusion: The dermoscopic patterns of blue-white veil and regular dotted vessels are indicators towards micronodular BCC in SOC and can help in prioritizing treatment.