56 year old patient, treated for cancer of the left lingual border by left glossectomy and left cervical lymphadenectomy, pT4N2bM0 positive surgical border, receiving concurrent adjuvant radiochemotherapy (cisplatin, three-dimensional conformal radiotherapy) (66Gy tumour bed, 54Gy cervical chains) which ended in March 2006. In November 2007 (18 months) we observed a right laterocervical mass, level II, 4cm and 29mm in CT. Negative extension study. Pathological anatomy: carcinoma. Considered unresectable by the Head and Neck Tumour Committee (CTCC) due to doubts about infiltration of the sternocleidomastoid muscle, we decided on chemotherapy (cisplatin six cycles) and re-evaluation. In May 2008 cervical MRI showed partial remission (24mm). After CTCC assessment, we decided to perform a right modified functional cervical lymphadenectomy with resection of the jugular vein and spinal nerve encompassed by the tumour mass, followed by interstitial HDRBT (June 2008), placing the vectors in the surgical procedure. After total excision, the tumour bed and organs at risk (carotid artery, brachial plexus) were identified by the surgeon and oncologist. We used a single-plane implant with five plastic tubes (separated by 1cm to minimise the risk of vascular toxicity) and Nucletron® comfort buttons (catheter-skin fixation). We used helical CT slices (5mm) for therapeutic simulation. Pathology showed metastasis of poorly differentiated squamous cell carcinoma in 4 of 7 resected nodes, all with extranodal infiltration. The HDRBT planning volume was defined as 5mm from the centre of the catheter. The total dose of 34Gy (10 fractions of 3.4Gy, 2 per day [6 hours apart], five consecutive days), was started five days after surgery.

As a multidisciplinary follow-up we evaluated: functional status, physical examination, toxicity, TSH value, and cervical CT scan. In February 2011, the patient is free of disease, in good general condition, without pain, as chronic toxicity: grade I soft tissue fibrosis (National Cancer Institute criteria [version 3.0]).