Seborrheic keratosis with focal acantholysis

Area of Science:

• Dermatopathology
• Histopathology
• Oncology

Background:

• Seborrheic keratosis (SK) is a common benign skin neoplasm.
• Acantholysis, a feature of some epithelial neoplasms, is rarely observed in SK.
• Distinguishing SK variants from other intraepidermal neoplasms is crucial for accurate diagnosis.

Observation:

• A 70-year-old male presented with multiple dome-shaped, black-brownish cutaneous tumors on his back.
• Clinical examination revealed lesions consistent with pigmented nevi or seborrheic keratoses.
• Dermoscopic evaluation suggested a benign neoplastic process.

Findings:

• Histopathological examination of the tumors revealed features of seborrheic keratosis, characterized by basaloid and squamoid cells.
• Significant acantholysis was noted within the intraepidermal tumor nests.
• The observed histopathological findings represented a variant of seborrheic keratosis with acantholysis, distinct from previously documented intraepidermal epithelioma-like tumor nests.

Implications:

• This case expands the known histopathological spectrum of seborrheic keratosis.
• Accurate diagnosis of this SK variant is important to avoid misclassification as a malignant neoplasm.
• Further research may elucidate the specific mechanisms driving acantholysis in this subtype of seborrheic keratosis.