Eccrine poroma: correlation of reflectance confocal microscopy and histopathology of horizontal sections

Correlation Between In Vivo Reflectance Confocal Microscopy and Horizontal Histopathology in Skin Cancer: A Review

“…Although the definitive diagnosis of EP is still based on conventional histopathology, non-invasive techniques, including dermoscopy and RCM, allow ruling out malignant conditions, and to suspect a benign adnexal neoplasm ( 28 , 29 ). Dermoscopically, EP usually presents milky red areas at the periphery of the lesion and a polymorphous vascular pattern in the center, including glomerular, flower-like and dotted vessels ( 30 ). RCM shows a uniformly well-circumscribed neoplasm, consisting of hyper-reflective clusters surrounded by a darker stromal component ( 28 , 30 ).…”

“…Dermoscopically, EP usually presents milky red areas at the periphery of the lesion and a polymorphous vascular pattern in the center, including glomerular, flower-like and dotted vessels ( 30 ). RCM shows a uniformly well-circumscribed neoplasm, consisting of hyper-reflective clusters surrounded by a darker stromal component ( 28 , 30 ). Neoplastic cells are bright and homogeneous in size and shape, with round and dark nuclei, and may be arranged around non-reflective rounded areas ( 28 , 30 ).…”

“…RCM shows a uniformly well-circumscribed neoplasm, consisting of hyper-reflective clusters surrounded by a darker stromal component ( 28 , 30 ). Neoplastic cells are bright and homogeneous in size and shape, with round and dark nuclei, and may be arranged around non-reflective rounded areas ( 28 , 30 ). Deeper sections show a richly vascularized stroma intermingled with tumor nests ( 28 , 30 ).…”

“…Neoplastic cells are bright and homogeneous in size and shape, with round and dark nuclei, and may be arranged around non-reflective rounded areas ( 28 , 30 ). Deeper sections show a richly vascularized stroma intermingled with tumor nests ( 28 , 30 ). RCM images of EP correspond well with HHS ( 28 , 30 ): neoplastic cells are monomorphic, cuboid-shaped, arranged in basaloid nests and occasionally forming round/slit-like ducts with eosinophilic material inside; these ducts strongly match with the non-reflective round dark areas visible with RCM and represent foci of ductal differentiation of EP.…”

“…Deeper sections show a richly vascularized stroma intermingled with tumor nests ( 28 , 30 ). RCM images of EP correspond well with HHS ( 28 , 30 ): neoplastic cells are monomorphic, cuboid-shaped, arranged in basaloid nests and occasionally forming round/slit-like ducts with eosinophilic material inside; these ducts strongly match with the non-reflective round dark areas visible with RCM and represent foci of ductal differentiation of EP. Bright uniformly shaped and sized cells interspersed within the tumor island or scattered in the upper dermis are often present at RCM in the pigmented variant of EP ( 28 ); these cells histologically correspond to melanocytes and melanophages, respectively.…”