The risk for recurrence after surgery alone varies according to localization.
Radiation therapy targets the area of the tumor because there is often microscopic residual disease despite "free" resection margins evaluated by light microscopy. In addition, regional lymph nodes are irradiated either for manifest regional metastases or because of the primary tumor's localization, and/or the T stage suggests high probability for microscopic disease in regional lymph nodes.
The interval between surgery and radiation therapy should be as short as possible, preferably 3-4 weeks (<5 weeks).
The target volume and dose are adapted for each patient.
- Postoperative radiation therapy is intended to remove microscopic residual disease and prevent and/or eradicate spreading to cervical lymph nodes.