Actinic Keratosis in Japan

• Actinic Keratosis (AK) in Japan:
  • tend to be multiple
  • 20% evolve into Squamous Cell Carcinoma (SCC)
  • clinical types: macular, horn, papular, actinic cheilitis. All types can be pigmented: atypical keratinocytes containing melanin granules in the cytoplasm
• Aging of AK and histological caracteristics:
  • early AKs:
    • no parakeratosis
    • atypical keratinocytes limited to the basal layer
    • no budding
  • developed AKs:
    • thick parakeratosis
    • budding in the papillary dermis
  • together with this, histological features of solar damage are also present: solar elastosis

Contributors

Dr Christophe Hsu – dermatologist. Geneva, Switzerland

Kimura T. Sundamaged Skin and Skin Cancer. Photodermatosis and Ethnicity in Asian Skin. 2014 (4) – 21st Regional Conference of Dermatology; Danang (Vietnam)