When is adjuvant radiotherapy recommended for a high risk squamous cell carcinoma of the skin (non-H&N) if the tumor is resected with widely negative margins and there is no perineural invasion?

There is limited high quality evidence to guide management of "widely" excised cutaneous squamous cell carcinomas. There is an excellent prospective study reporting the outcomes of margin-negative excisions using techniques similar to Mohs surgery suggesting that there are several risk factors for l...