9th July 2023

Squamous Cell Carcinoma (SCC)

SCC risk factors are similar to BCCs, but also include a background of Bowen’s disease (SCC in-situ), chronic ulcers (leading to a Marjolin ulcer), smoking, HPV infections and immunosuppression. Presentation is often of a rough or scaly papule/plaque that may bleed and later ulcerate. SCCs are more aggressive than BCCs, with a greater potential to metastasise, requiring a 2WW referral. Lesion size informs the full-thickness biopsy margin:

• Low-risk lesion: ≤20mm: ≥4mm margins
• High-risk lesion: >20mm: ≥6mm margins

Biopsy confirms diagnosis, assesses histological margins and level of differentiation. This informs management and prognosis. Invasive SCCs penetrate beyond the basement membrane, for which further body imaging should be considered, e.g. CT, MRI.

Table 2: SCC types with potential treatment options

Bowen’s disease on the finger

Image Source: Wikimedia Commons (2009). Bowen11, Licensed under a creative commons licence. Available for free at: https://commons.wikimedia.org/wiki/File:Bowen11.jpg (Accessed on: 3 November 2021).