Male, 10 years. Papule, skin of back.
Balloon cell naevus
BALLOON CELL NAEVI:
- Dermal or compound naevus of usual type
- Presence of groups or sheets of 'balloon' naevus cells with copious fine vacuolated cytoplasm
- Balloon cells stand out from surrounding population of unremarkable naevus cells
- No 'maturation' of balloon cell component
- A few ascending balloon cells within the epidermis may be present. Because of the ballooning phenomenon, stey stand out more more distinctly in H&E sections than small asecnding naevus cells seen in other naevi. This can be a source of overdiagnosis
- No nuclear atypia
- No, or hardy any, mitotic activity
Schrader WA, Helwig EB. Cancer. 1967; 20: 1502-14.