Treatment will depend on the location, extent of recurrent or residual disease, previous management and the patient’s preferences.

The management for people with locally recurrent keratinocyte cancer is more urgent because patients have an increased risk of further regional recurrence and/or distant metastases. Treatment may include the following options.

In managing people with locally recurrent BCCs, treatment may include:

• surgical excision – excision of the lesion with the scar and any previously treated area is usually necessary
• radiation therapy – as primary treatment to a locally recurrent BCC or as adjuvant treatment after re-excision
• margin control surgery – for example, Mohs micrographic surgery (Cancer Council Australia Keratinocyte Cancers Guideline Working Party 2019).

In managing people with locally recurrent SCCs, treatment may include:

• surgical excision – excision of the lesion with the scar and any previously treated area is usually necessary
• radiation therapy – adjuvant radiation therapy following surgery should be considered for incompletely excised (residual) and locally recurrent SCCs, especially high-risk SCCs (e.g. rapidly growing tumours, recurrent disease, close margins [< 5 mm], perineural or lymphovascular invasion, in-transit metastases, and regional nodal involvement) (Cancer Council Australia Keratinocyte Cancers Guideline Working Party 2019).

In the management for people with nodal recurrent SCCs, treatment may include:

• surgery – this is the primary treatment for an SCC that has metastasised to the lymph nodes
• adjuvant radiation therapy – adjuvant radiation therapy following nodal surgery should be considered given high-risk disease following a complete excision (e.g. rapidly growing tumours, recurrent disease) (Cancer Council Australia Keratinocyte Cancers Guideline Working Party 2019)
• systemic therapy is available for a locally advanced or metastatic SCC and BCC that is not surgically resectable or suitable for radiation therapy – for metastatic SCCs, immunotherapy (e.g. checkpoint inhibitors), targeted therapy (e.g. epidermal growth factor inhibitors) and chemotherapy (as part of multimodal therapy or standalone therapy) are options that have demonstrated efficacy; for locally advanced or metastatic BCCs, targeted hedgehog inhibitor therapy (vismodegib and sonidegib) may be used for tumour suppression.

Some medications can predispose to keratinocyte cancer including immunosuppressives and photosensitizers such as voriconazole.

The potential goals of treatment should be discussed, respecting the patient’s cultural values. Wherever possible, written information should be provided.

Encourage early referral to clinical trials or accepting an invitation to participate in research.