Paediatric desmoid tumour of the head and neck: a complete response to chemotherapy and the paradigm shift towards non-surgical management.

Desmoid tumours are rare locally aggressive mesenchymal tumours with a high local recurrence rate, particularly in the head and neck locations. We present the case of a 5-year-old child with a locally invasive inoperable desmoid tumour of the masticator space who underwent a low-dose chemotherapy regimen for 17 months, obtaining a long-term complete response. Definitive evidenced-based treatment guidelines are lacking. Therefore, paediatric patients should be managed by specialised multidisciplinary teams to try to achieve the best tumour control while minimising treatment associated morbidity and mortality. Available treatment options include surgery, radiotherapy and different systemic medical therapies. Whereas traditionally, surgery was the mainstay of treatment, more conservative options have increasingly shown adequate tumour control with little associated morbidity. In this decision making it is mandatory to take into account the patient's age, tumour location and extension, and potential short-term and long-term treatment-related sequelae to minimise functional and cosmetic compromise.