Head and neck sarcomas in adulthood: current trends and evolving management concepts.

Sarcomas are rare, malignant bone and soft-tissue tumours of mesenchymal origin, and their overall incidence accounts for 1% and 0.2%, respectively, of all malignancies. The aim of this article is to provide a reference on the evolving management concepts and trends of treatment of adult sarcomas of the head and neck in a major head and neck sarcoma centre. Early diagnosis remains a challenge due to non-specific symptomatology. Imaging such as ultrasound (US), magnetic resonance (MRI), computed tomography (CT), and positron emission tomography (PET) CT assist with diagnosis and staging, and biopsy is essential for diagnosis, tumour differentiation, and grading. Staging is dependent on histological grade, size of tumour, and metastasis. Sarcomas spread via the haematogenous route. Adequate clearance of locoregional disease and prevention of distant micrometastases are key to improved disease-free survival outcomes so multimodal treatment at a sarcoma reference centre is imperative. In the head and neck, the treatment for most bone sarcomas is neoadjuvant chemotherapy followed by compartmental resection. The interim tumour response to neoadjuvant chemotherapy is evaluated by PET CT and MRI. Heavy-particle therapy (proton beam) in combination with surgery is increasingly being used to treat otherwise unresectable disease, particularly in children. For soft tissue sarcomas of the head and neck, treatment is complex and depends on grade. Surgery is the principle mode of treatment in low-grade tumours that are amenable to resection. High-grade tumours can be treated with neoadjuvant chemotherapy followed by surgery and radiotherapy. In such cases, the response to the chemotherapy might be used as a guide of potential biological aggressiveness, and has an impact on the planning of the operation and the type and extent of radiotherapy. As a general rule, radiotherapy is reserved for high-grade, advanced soft-tissue sarcomas of the head and neck. Those of bone are radioresistant, and radiotherapy is only administered for palliative purposes when no surgical option exists, an exception being Ewing sarcoma. The role of proton beam therapy is promising, but to our knowledge no long-term data currently exist. The survival advantage of innate immune-modulation remains uncertain for disease in the head and neck.