Three-dimensional conformal radiotherapy (3D-CRT) versus intensity modulated radiation therapy (IMRT) in squamous cell carcinoma of the head and neck: A randomized controlled trial

Abstract Purpose To compare three-dimensional conformal radiotherapy (3D-CRT) with intensity modulated radiation therapy (IMRT) in curative-intent irradiation of head-neck squamous cell carcinoma (HNSCC). Methods Previously untreated patients with biopsy-proven squamous carcinoma of oropharynx, larynx, or hypopharynx (T1-3, N0-2b) were randomly assigned using computer-generated permuted-block design to either 3D-CRT or IMRT, with incidence of physician-rated Radiation Therapy Oncology Group (RTOG) grade 2 or worse acute salivary gland toxicity as primary end-point. Results Between 2005 and 2008, 60 patients randomly allocated to either 3D-CRT ( n = 28 patients) or IMRT ( n = 32) were included and analyzed on an intention-to-treat basis. The proportion [95% confidence intervals (CI)] of patients with RTOG grade 2 or worse acute salivary gland toxicity was significantly lesser in the IMRT arm [19 of 32 patients (59%, 95% CI: 42–75%)] as compared to 3D-CRT [25 of 28 patients (89%, 95% CI: 72–97%; p = 0.009)]. Late xerostomia and subcutaneous fibrosis were also significantly lesser with IMRT. There was significant recovery of salivary function over time in patients treated with IMRT ( p -value for trend = 0.0036). At 3-years, there were no significant differences in loco-regional control or survival between the two arms. Conclusion IMRT significantly reduces the incidence and severity of xerostomia compared to 3D-CRT in curative-intent irradiation of HNSCC.