OBJECTIVES: The aim of the present study was to estimate the current number of patients with cutaneous squamous cell carcinoma (CSCC), with metastatic or recurrent disease and eligible for systemic therapies.

METHODS: A literature review was carried out to collect incidence and prevalence data about metastatic or recurrent CSCC. To complement it, the national diagnostic-related-group (DRG) database for the year of 2017 was used to identify and characterize CSCC patients. Additionally, an expert panel with five physicians was implemented to gather supplementary epidemiological data via individual electronic questionnaires.

RESULTS: In the DRG database, 12,064 Portuguese patients with non-melanoma skin cancer and 2,727 patients with CSCC were identified. Among CSCC patients, metastatic and recurrence rates of 3.5% and 5.0%, respectively, were estimated; therefore, there are 231 patients with advanced CSCC (95 metastatic and 136 recurrent). According to the expert panel, metastatic CSCC are potentially eligible for systemic therapy, and recurrent CSCC are expected to be treated with surgery or radiotherapy (95%, 129 patients) being only 5% (7 patients) treated with systemic treatment. Subsequently, 25% (32 patients) of those treated with surgery or radiotherapy will require systemic treatment. Thus, a total of 135 CSCC patients are expected to be eligible for systemic therapy. However, due to various possible restriction factors, like advanced age, high performance status or immunosuppression, only 95% of potentially eligible patients will actually receive systemic therapy (128 patients). Finally, considering that about 30% of the overall patients in Portugal are treated outside the Portuguese National Health Service, the number of metastatic or recurrent CSCC patients to be treated with systemic therapies in Portugal is 183.

CONCLUSIONS: Given the limited published epidemiological data about CSCC, this study uses complementary sources to characterize CSCC treatment in Portugal, allowing to estimate a total number of 183 patients on systemic therapies.