Abstract Background Basal cell carcinoma (BCC) dermoscopy is key to lower the biopsy threshold of suspicious lesions. There is a scarcity of published data on the dermoscopy of very small BCC (≤3 mm) and its differences from larger BCCs. Objective To describe and compare dermoscopic features of BCCs measuring ≤3 mm, with those from 3 to 10 mm. Methods An analytical cross-sectional study, included biopsy-proven BCCs that had dermoscopic photographic images, between January 2017 and December 2022 in a Skin Cancer Center in Medellín, Colombia. Demographic, clinic-pathological and dermoscopic features were compared between very small BCCs (vsBCCs) and a reference group. Results A total of 326 BCCs in 196 patients were included, of whom 60% were male. The most common Fitzpatrick phototype was III. vsBCCs accounted for 25% of the lesions (81/326). Face and neck were the most frequent locations (53%), especially in very small tumors. The nodular type was more common in very small tumors than in larger lesions, the superficial type was less frequent, and aggressive types were equally prevalent in both groups. On dermoscopy, very small tumors were statistically more likely to present pigmented structures than reference lesions, especially blue-gray dots (67% vs. 54%), vessels were less frequent, particularly short-fine telangiectasias (SFT) (52% vs. 66%), as were other structures such as shiny white structures (SWS), ulceration, micro-erosions, and scales. Study limitations Latin-American sample, lacks information on dark phototypes Conclusions Pigmented structures, especially blue-gray dots, were most common in vsBCCs when compared to larger lesions; SFT, SWS and other findings were less prevalent.

Resumen El exantema intertriginoso y flexural simétrico por fármacos (SDRIFE) es una toxicodermia que se presenta con exantema limitado a pliegues, sobretodo en región glútea y genital, y representa una reacción a la exposición sistémica a un medicamento sin sensibilización previa. Presentamos el caso de una paciente mujer adulta previamente sana, que consulta por este tipo de reacción medicamentosa asociada al uso de piroxicam intramuscular, manejada de forma exitosa con antihistamínicos, esteroides tópicos y sistémicos.

Abstract Symmetrical drug related intertriginous and flexural exanthema is a cutaneous drug eruption that is characterized by exanthema limited to creases, buttocks and the upper inner thighs. It represents a reaction to systemic exposure to a drug, without previous sensitization. We present the case of a woman, previously healthy, who consulted due to this drug reaction after being injected with piroxicam, who was successfully treated with antihistamines, topical and systemic corticosteroids.