The radiotherapy protocol will include two dose-escalation regimens. The dose in hypoxic tumor volume will be escalated either by conventional RT or stereotactic radiotherapy technique. Concurrent chemotherapy cisplatin will be administered weekly 35-40 mg/m2 or every three weeks 80-100 mg/m2. The parameter of cumulative cisplatin dose of 200 mg/m2 during the whole course of radiotherapy will be also taken into account. Patients will be examined and monitored at least every two weeks.~Target volumes and dose and fractionation:~Definition of gross tumor volumes (GTV), clinical target volumes (CTV) and planning target volumes (PTV) will follow recommendations of DAHANCA, EORTC and RTOG guidelines.~The conventional radiotherapy protocol:~Standard fractionation regimen: 70 Gy/54 Gy in 33 fractions GTV primary - CTV - PTV (5+5mm): for dose 70 Gy in 33 fractions GTV LN bulky (> 3cm) - PTV (5mm): for dose 70 Gy in 33 fractions LN low risk (for elective irradiation) - CTV - PTV (3mm-5mm): for dose 54 Gy in 33 fractions~Dose escalated radiotherapy protocol:~Dose escalated radiotherapy protocol: 75,9 - 79,2 Gy in 33 fractions GTV hypoxic or any hypoxic LN > 2cm - PTV (0mm): dose 75,9 - 79,2 Gy in 33 fractions (Contours must be subtracted and reduce by 3mm in case of close relation to the skin, bones or large blood vessels) GTV primary - CTV - PTV (5+5mm): for dose 70 Gy in 33 fractions LN low risk (for elective irradiation) - CTV - PTV (3mm-5mm): for dose 54 Gy in 33 fractions
Hypoxia occurs in about 80% of head and neck tumors. Based on experimental and clinical data, hypoxia is a useful parameter for pretherapeutic stratification. These radioresistant regions can be detected with FMISO PET/CT. Moreover, hypoxic subvolumes of tumors can be evolving as target volumes for radiotherapy (dose painting) in hypoxia imaging-based dose escalation.