This benign lesion is grouped within the cutaneous cysts
Histology of pigmented follicular cyst
Scanning power view demonstrates a unilocular cystic structure within the dermis (Figure 1). Higher power reveals a thin epithelial lining with a retained granular layer (Figures 2 and 3). Within the cyst cavity are loose keratin fragments and numerous pigmented terminal hair shafts (Figures 2 and 3).
Pigmented follicular cyst pathology
Differential diagnosis of pigmented follicular cyst
Vellous hair cyst: In this lesion the cyst cavity contains small vellous hairs lacking pigmentation.
Epidermal inclusion cyst: Hair fragments are absent.