Stereotactic radiotherapy as planned boost after definitive radiotherapy for head and neck cancers: Systematic review

Abstract

Management of locoregionally advanced head and neck cancers (HNCs) remains a challenge. Some groups have attempted to use stereotactic radiotherapy (SBRT) to deliver “boost” treatment following conventional radiotherapy to improve local control (LC) and overall survival (OS), while aiming for acceptable toxicities. Medline, EMBASE, and Cochrane Library databases were queried for SBRT as curative‐intent planned boost in HNC after conventional radiotherapy. Individual studies were reviewed from inception until January 2021, extracting patient, treatment, and outcome data. Nine studies met inclusion criteria, representing 454 unique patients treated with curative intent across multiple head and neck sites with conventional radiotherapy. At 3 years, median LC was 92% (90%–98%), and median OS was 80% (75%–91%). Seven treatment‐related grade 5 toxicities (1.5%) were reported. Despite acceptable LC and OS rates, there were severe treatment‐related late toxicities. As such, SBRT boost should only be used in investigational settings until more data is available.

Dosimetric comparison of postoperative interstitial high-dose-rate brachytherapy and modern external beam radiotherapy modalities in tongue and floor of the mouth tumours in terms of doses to critical organs

“…32 Stereotactic contouring protocols are very heterogeneous, but generally 1-5 mm for GTV-CTV extension and 2-3 mm for CTV-PTV extension in head and neck cancers. 33 In our analysis 2 mm for CTV-PTV extension was used.…”

Stereotactic ablative radiotherapy for treating primary head and neck cancer and locoregional recurrence: A comprehensive review of the literature

“…While SABR offers reduced impact on QoL and may be particularly beneficial for patients unable to tolerate more aggressive therapies, its role as a primary treatment requires careful consideration, as the majority of existing evidence is of low level and/or applies to the palliative and re-irradiation setting [9] , [10] , [11] . Furthermore, the use of SABR as a boost in treatment for locally advanced disease presents a novel approach, albeit with limited supporting data [12] .…”

Expanding the role of combined immunochemotherapy and immunoradiotherapy in the management of head and neck cancer (Review)

“…Combinations of anti-CTLA-4 and anti-PD-1 antibodies show a synergistic effect in patients with melanoma and are currently being tested in patients with stage III HNSCC ( 156 ). The anti-CTLA-4 antibody tremelimumab in combination with the anti-PD-L1 antibody durvalumab in patients with metastatic HNSCC demonstrated an increased efficacy compared with either tremelimumab or durvalumab monotherapy ( 159 ). Numerous antibodies have additionally been scrutinized in stage I/II preliminary studies for patients with HNSCC ( 160 ).…”