Skin: Role of radiotherapy in non-melanoma skin cancer

Why C is correct

The European interdisciplinary cSCC guideline states that adjuvant radiotherapy should be considered in cSCC of the head and neck with regional nodal metastases and extracapsular extension. This patient has parotid nodal disease with extensive extracapsular extension after surgery, so adjuvant nodal radiotherapy is the appropriate recommendation.

And why the others are not

• AIncorrect: clear primary margins do not negate the high regional relapse risk from nodal disease with extracapsular extension, where adjuvant radiotherapy is advised.
• BIncorrect: Hedgehog pathway inhibitors such as vismodegib are used for advanced basal cell carcinoma, not for cutaneous squamous cell carcinoma.
• DIncorrect: adjuvant chemotherapy alone is not the recommended approach; adjuvant radiotherapy is the guideline-supported option in this high-risk nodal setting.
• EIncorrect: cemiplimab (anti-PD-1) is first-line systemic therapy for locally advanced or metastatic cSCC not amenable to curative surgery or radiation, not for resectable nodal disease that has been operated on.

Source European interdisciplinary guideline on invasive cutaneous squamous cell carcinoma: Part 2 Treatment — Stratigos AJ, Garbe C, Dessinioti C, et al. European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 2. Treatment. Eur J Cancer. 2020;128:83-102.