Cutaneous lymphadenoma with ductal differentiation

Area of Science:

• Dermatopathology
• Surgical Pathology
• Oncology

Background:

• Cutaneous lymphadenoma (CL) is a recently identified neoplasm with an unclear origin.
• Histological features include well-circumscribed nodules, basaloid cells in lobules, peripheral palisading, and a dense lymphoid infiltrate.
• Previous descriptions noted limited adnexal differentiation, with only occasional sebaceous or follicular differentiation.

Observation:

• Two cases of cutaneous lymphadenoma were examined using histological and immunohistochemical methods.
• Tumor lobules in these cases exhibited foci of ductal differentiation.
• Luminal positivity for CEA (carcinoembryonic antigen) and EMA (epithelial membrane antigen) was observed in these ductal foci.

Findings:

• The study identified ductal differentiation within cutaneous lymphadenoma lobules.
• Immunohistochemistry confirmed luminal expression of CEA and EMA, indicative of ductal structures.
• These findings provide new insights into the potential histogenesis of CL.

Implications:

• The presence of ductal differentiation suggests that some cutaneous lymphadenomas may originate from immature sweat gland precursors.
• This finding could refine the classification and understanding of cutaneous lymphadenoma.
• Further research is warranted to confirm the sweat gland origin and explore therapeutic strategies for CL.