Squamous Cell Carcinoma In Situ (Bowen Disease)

Squamous Cell Carcinoma In Situ (Bowen Disease)

David Cassarino, MD, PhD

Bowen disease (SCCis) is characterized by a proliferation of atypical intraepidermal keratinocytes filling the entire epidermis, including the granular layer image. Many of the cells show cytoplasmic clearing image.

High magnification of Bowen disease shows prominent cytologic atypia, an atypical mitotic figure image in the mid-epidermis, and apoptotic cells image.



  • Squamous cell carcinoma in situ (SCCis)


  • Bowen disease

  • Squamous intraepithelial neoplasia (SIN)


  • Full thickness intraepidermal atypia of squamous keratinocytes often with numerous mitotic figures and apoptotic cells


Sun Exposure

  • Chronic UV radiation strongly implicated in SCCis


  • Increased risk of developing SCCis in immunosuppressed patients, especially organ transplant recipients

HPV Infection

  • Some cases of SCCis are related to HPV infection, particularly in anogenital sites

    • SCCis also may arise in verrucae and condylomata



  • Most common on head and neck region, other sun-exposed sites


  • Scaly patch or plaque lesion

  • Ulceration and hemorrhage may be present


  • Surgical approaches

    • Complete surgical excision is standard and definitive therapy

    • Mohs surgery often performed for facial lesions to minimize amount of tissue taken

    • Electrodessication and curettage (ED&C) may also be used

  • Drugs

    • Topical therapy with immunomodulators, including imiquimod or 5-fluorouracil, may be used

      • Patients with extensive lesions or poor surgical candidates


  • Excellent in most cases

  • Small risk for invasive squamous cell carcinoma

    • Greater risk in patients with immunosuppression or numerous lesions


General Features

  • Broad, superficial lesion with epidermal thickening and overlying scale


Histologic Features

  • Atypical intraepidermal proliferation of squamous cells extending into upper levels of the epidermis

    • Basilar keratinocytes are often spared, leading to so-called “eyeliner” sign

  • Overlying parakeratosis often diffusely present, without skip areas over adnexal structures

  • Follicular epithelial involvement is typically seen

  • Cells are usually markedly enlarged and atypical appearing, with nuclear hyperchromasia and enlarged nucleoli

  • Numerous intraepidermal mitotic figures and apoptotic figures typically present

Cytologic Features

Jul 8, 2016 | Posted by in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Squamous Cell Carcinoma In Situ (Bowen Disease)

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