The superior mediastinum contains a considerable number of lymph nodes. Although occasionally involved in head and neck cancer, there are not many reports of mediastinal dissection in the practice of head and neck surgery. We present a group of seven patients with head and neck tumours that underwent mediastinal dissection in our department. Three patients are alive and free of disease six months to three years after the operation, two are alive with disease four and five years after the procedure, and two patients died peri-operatively. According to reviewed current literature, direct invasion of cancer of the head and neck to the mediastinum or mediastinal lymph node involvement is uncommon. Yet, mediastinal dissection provides the only chance for cure in selected cases.