Adnexal tumors belong to a heterogeneous group of mostly benign neoplasms with appendageal (eccrine, apocrine, follicular, and sebaceous)
differentiation. The lesions shown in Figures 1, 2, and 3 were located on the chest, neck, and abdomen of a 39-year-old woman, a 71-year-old man, and another 39-year old woman, respectively. In lesions 1 and 2, a clinical diagnosis of basal cell carcinoma (Figure 1A and Figure 2A) was strengthened by dermoscopy, which revealed leaflike areas (Figure 1B) and arborizing vessels (Figure 1B and Figure 2B). In lesion 3 a diagnosis of collision tumor (seborrheic keratosis with basal cell carcinoma) was made for the presence of multiple comedolike openings and arborizing vessels (Figure 3). Histopathologic examination revealed an angiohistiocytoma,
a hydradenoma, and an intraepidermal poroma (with features of acrosyringeal nevus) in lesions 1, 2 and 3, respectively. Clinically and dermoscopically,
adnexal tumors may often mimic basal cell carcinoma; thus, histopathologic evaluation remains the gold standard for diagnosis.