Systemic treatments for thymic tumors: a narrative review

: Thymic epithelial tumours (TETs) are rare tumours originating from the thymus. Considering the rarity of this disease, the management of TETs is still challenging and difficult. In fact, all the worldwide clinical practice guidelines are based on data from retrospective analyses, prospective single arm trials or experts' opinions. The results of combined modality therapy (chemotherapy, surgery, radiotherapy) in thymic malignancies are reasonably good in less advanced cases whereas in case of advanced (unsuitable for surgery) or metastatic disease, a platinum-based chemotherapy is considered standard of care. Unfortunately, chemotherapy in the palliative setting has modest efficacy. Moreover, due to the lack of known oncogenic molecular alterations, no targeted therapy has been shown to be efficient for these tumours. In order to offer the best diagnostic and therapeutic tools, patients with TETs should be managed with a continuous and specific multidisciplinary expertise at any step of the disease, especially in the era of a novel coronavirus disease (COVID-19). Current evidences show that cancer patients might have more severe symptoms and poorer outcomes from COVID-19 infection than general population. With the exception of the patients carrying a Good's syndrome, there is no evidence that patients with TETs present a higher risk of infection compared with other cancer patients and their management should be the same. The aim of this review is to summarize the existing literature about systemic treatments for TETs in all clinical setting (local and locally advanced/metastatic disease) exploring how these therapeutic strategies have been managed in the COVID-19 era.