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Radiation Therapy
Source: Oropharyngeal Cancer Treatment (PDQ®)–Health Professional Version, National Cancer Institute.
Source updated: May 14, 2025 · Captured 2026-09-09.
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Context: Treatment Option Overview for Oropharyngeal Cancer
A review of published clinical results of radiation therapy for head and neck cancer suggested a significant loss of local control when the administration of radiation therapy was prolonged. Therefore, extending standard treatment schedules is detrimental.[11,12]
Patients who are smokers appear to have lower response rates and shorter survival times than those who do not smoke while receiving radiation therapy.[13] Counseling patients to stop smoking before beginning radiation therapy may be beneficial.
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Intensity-modulated radiation therapy (IMRT) has become a standard technique for head and neck radiation therapy. IMRT allows a dose-painting technique, also known as a simultaneous-integrated-boost (SIB) technique, with a dose per fraction slightly higher than 2 Gy, which allows slight shortening of overall treatment time and increases the biologically equivalent dose to the tumor.
Evidence (definitive radiation therapy):
IMRT was studied in a phase II trial (RTOG-0022 [NCT00006360]) of 69 patients with stages T1 to T2, N0 to N1, M0 oropharyngeal carcinoma who were treated with primary radiation therapy without chemotherapy.[14] The median follow-up was 2.8 years. The prescribed planning target volume (PTV) dose to the primary tumor and involved nodes was 66 Gy at 2.2 Gy per fraction over 6 weeks. Subclinical PTVs received simultaneously 54 to 60 Gy at 1.8 to 2.0 Gy per fraction using an SIB technique. The following results were observed:The RTOG-0022 study showed high control rates and the feasibility of IMRT at a multi-institutional level; the study also showed high tumor control rates and reduced salivary toxicity compared with previous Radiation Therapy Oncology Group (RTOG) studies. However, major target underdose deviations were associated with a higher locoregional failure rate.
IMRT was studied in a phase II trial (RTOG-0022 [NCT00006360]) of 69 patients with stages T1 to T2, N0 to N1, M0 oropharyngeal carcinoma who were treated with primary radiation therapy without chemotherapy.[14] The median follow-up was 2.8 years. The prescribed planning target volume (PTV) dose to the primary tumor and involved nodes was 66 Gy at 2.2 Gy per fraction over 6 weeks. Subclinical PTVs received simultaneously 54 to 60 Gy at 1.8 to 2.0 Gy per fraction using an SIB technique. The following results were observed:The RTOG-0022 study showed high control rates and the feasibility of IMRT at a multi-institutional level; the study also showed high tumor control rates and reduced salivary toxicity compared with previous Radiation Therapy Oncology Group (RTOG) studies. However, major target underdose deviations were associated with a higher locoregional failure rate.
The 2-year estimated locoregional failure rate was 9%. Two of four patients (50%), who had major underdose deviations, had locoregional failure compared with 3 of 49 patients (6%) without such deviations (P = .04).
IMRT was studied in a phase II trial (RTOG-0022 [NCT00006360]) of 69 patients with stages T1 to T2, N0 to N1, M0 oropharyngeal carcinoma who were treated with primary radiation therapy without chemotherapy.[14] The median follow-up was 2.8 years. The prescribed planning target volume (PTV) dose to the primary tumor and involved nodes was 66 Gy at 2.2 Gy per fraction over 6 weeks. Subclinical PTVs received simultaneously 54 to 60 Gy at 1.8 to 2.0 Gy per fraction using an SIB technique. The following results were observed:The RTOG-0022 study showed high control rates and the feasibility of IMRT at a multi-institutional level; the study also showed high tumor control rates and reduced salivary toxicity compared with previous Radiation Therapy Oncology Group (RTOG) studies. However, major target underdose deviations were associated with a higher locoregional failure rate.
Maximal late toxicities with a grade of 2 or higher were skin (12%), mucosa (24%), salivary (67%), esophagus (19%), and osteoradionecrosis (6%).
IMRT was studied in a phase II trial (RTOG-0022 [NCT00006360]) of 69 patients with stages T1 to T2, N0 to N1, M0 oropharyngeal carcinoma who were treated with primary radiation therapy without chemotherapy.[14] The median follow-up was 2.8 years. The prescribed planning target volume (PTV) dose to the primary tumor and involved nodes was 66 Gy at 2.2 Gy per fraction over 6 weeks. Subclinical PTVs received simultaneously 54 to 60 Gy at 1.8 to 2.0 Gy per fraction using an SIB technique. The following results were observed:The RTOG-0022 study showed high control rates and the feasibility of IMRT at a multi-institutional level; the study also showed high tumor control rates and reduced salivary toxicity compared with previous Radiation Therapy Oncology Group (RTOG) studies. However, major target underdose deviations were associated with a higher locoregional failure rate.
Longer follow-up revealed reduced late toxicity in all categories. Xerostomia grade 2 or higher was observed in 55% of patients at 6 months but was reduced to 25% of patients at 12 months and 16% of patients at 24 months.
Similar nonrandomized multicenter studies used fractionally escalated doses, ranging from 2.3 to 2.5 Gy with IMRT. These doses have been safe when given without concurrent chemotherapy for pharyngolaryngeal T2N0, T2N1, or laryngeal T3N0 SCC.[15-19]
Similar nonrandomized multicenter studies used fractionally escalated doses, ranging from 2.3 to 2.5 Gy with IMRT. These doses have been safe when given without concurrent chemotherapy for pharyngolaryngeal T2N0, T2N1, or laryngeal T3N0 SCC.[15-19]
No toxicity difference was observed between the different dose-escalated groups.
A randomized trial (PARSPORT [NCT00081029]) conducted in the United Kingdom compared conventional 3-dimensional conformal radiation therapy with IMRT. The following results were observed:[20][Level of evidence A1]
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A randomized trial (PARSPORT [NCT00081029]) conducted in the United Kingdom compared conventional 3-dimensional conformal radiation therapy with IMRT. The following results were observed:[20][Level of evidence A1]
The rate of xerostomia was significantly lower in the IMRT group than in the conventional group.
A randomized trial (PARSPORT [NCT00081029]) conducted in the United Kingdom compared conventional 3-dimensional conformal radiation therapy with IMRT. The following results were observed:[20][Level of evidence A1]
Fatigue was more prevalent in the IMRT group.
A randomized trial (PARSPORT [NCT00081029]) conducted in the United Kingdom compared conventional 3-dimensional conformal radiation therapy with IMRT. The following results were observed:[20][Level of evidence A1]
No significant differences were seen in nonxerostomia late toxicities, locoregional control, or OS at 24 months.
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