Background: Image-guided intensity-modulated radiotherapy (IG-IMRT) is increasingly being used to treat patients with soft-tissue sarcoma (STS) of the head and neck. Although there is no comparison between IMRT and conventional radiation therapy (CRT) concerning their efficacy. In this analysis, we compared CRT and IMRT outcomes for head and neck STS. Patients and Methods: Sixty-seven patients who underwent radiotherapy between 1994 and 2017 were identified. Results: The median follow-up was 31 months. Of the 67 patients, 34% were treated with CRT technique and 66% with IG-IMRT. The locoregional relapse rate following IMRT was 21% versus 70% with CRT (p<0.001) and the 5-year locoregional control was 69% versus 28%, respectively (p=0.01). IG-IMRT was associated with non-significant, less acute, and chronic adverse events. In the multivariate analysis, a significant influence of radiation technique on locoregional control was confirmed (p=0.04). Conclusion: IG-IMRT seems to be associated both with higher locoregional control as well as lower acute and chronic toxicities. Head and neck soft-tissue sarcoma (STS) is a rare tumor arising from soft tissue, and represents ~10% of all sarcomas (1, 2). Thus, patient groups presented in such studies are often small and non-homogeneous. STS in the head and neck, specifically, requires special management due to both its location and threat to numerous organs. Prognosis, as well as treatment, of head and neck sarcomas differs from that of other locations, owing to the limited scope for wide local excision due to the presence of important nearby structures and organs. Such localizations bear approximately 10% lower absolute difference in 5-year locoregional control (LRC) and overall survival (OS) as compared to sarcoma of the extremities (1-4). In addition to surgical resection, radiotherapy (RT) represents an important cornerstone of treatment. For instance, the most common RT indications are high tumor grade, large tumor, close resection margins, and locally advanced stage (2, 5). Recently, the TNM classification system has been revised to consider tumor size more heavily for better prognostic stratification (6). The role of adjuvant chemotherapy (CTX) is unclear and depends on many factors, such as histological subtype, grade. Therefore, treatment must be individualized and made on a case-by-case basis (5, 7). Emerging treatments, such as use of checkpoint inhibitors, is currently under investigation as an adjuvant therapy with the hope of reducing risk of relapse (8). Image-guided intensity-modulated radiotherapy (IMRT) aims to deliver a homogeneous dose distribution into the tumor bed with maximum protection or sparing of organs at risk (OAR), with optimal positioning of patients (9). In addition, interfractional imaging may allow further adaptive planning in order to escalate the radiation dose, suggesting an improvement of outcome in comparison with conventional radiotherapy (CRT) (10, 11).
