Dose and fractionation
Patients are treated with photons
. The dose rate should be between 0.5 and 5 Gy per minute. A homogeneous dose should always be striven for, possibly with use of a compensation dose.
It is important to maintain the planned treatment schedule.
Standard treatment
All fields are treated at each fractionation.
- Radically operated (R0) will have 50 Gy (T1-2) or 60 Gy (T3-4)
- Non-radically operated (R1/R2) and levels with extracapsular growth will have 66 Gy
- Elective lymph nodes will have 46-50 Gy
- 5 fractionations per week
- 1 fractionation daily, Monday-Friday.
The interval between surgery and radiation therapy should be as short as possible, preferably 3-4 weeks (<5 weeks).
Postoperative irradiation to at least 60 Gy after a neck lymphadenectomy done if there is:
- extranodal growth in one or more lymph nodes
- tumor infiltration in lymph nodes at multiple levels
- tumor tissue in soft tissue/skin
- involved resection margins/residual tumor
- mid-linear primary tumors (contralateral neck field)
Some of the above mentioned factors may require local boosts to higher doses.
Unforeseeable interruptions
Not more than one extra fractionation per week is the goal, and missed sessions should be given within one week. This is done by giving an extra fractionation on the weekend, or the same day as the planned fractionation with ≥ 6 hours interval.