Image guided high-dose-rate brachytherapy versus volumetric modulated arc therapy for head and neck cancer: A comparative analysis of dosimetry for target volume and organs at risk

Abstract

BackgroundThe aim of the study was to present dosimetric comparison of image guided high-dose-rate brachytherapy (IGBT) with volumetric modulated arc therapy (VMAT) for head and neck cancer regarding conformity of dose distribution to planning target volume (PTV) and doses to organs at risk (OARs).Patients and methodsThirty-eight consecutive patients with T1-4 mobile tongue, floor of mouth and base of tongue cancer treated with IGBT were selected. For these patients additional VMAT treatment plans were also prepared using identical computed tomography data. OARs and PTV related parameters (e.g. V98, D0.1cm3, Dmean, etc.) were compared.ResultsMean V98 of the PTV was 90.2% vs. 90.4% (p > 0.05) for IGBT and VMAT, respectively. Mean D0.1cm3 to the mandible was 77.0% vs. 85.4% (p < 0.05). Dmean to ipsilateral and contralateral parotid glands was 4.6% vs. 4.6% and 3.0% vs. 3.9% (p > 0.05). Dmean to ipsilateral and contralateral submandibular glands was 16.4% vs. 21.9% (p > 0.05) and 8.2% vs. 16.9% (p < 0.05), respectively.ConclusionsBoth techniques showed excellent target coverage. With IGBT dose to normal tissues was lower than with VMAT. The results prove the superiority of IGBT in the protection of OARs and the important role of this invasive method in the era of new external beam techniques.

The value of brachytherapy in the age of advanced external beam radiotherapy: a review of the literature in terms of dosimetry

“…A comparative dosimetric analysis of target volume and OARs between interstitial HDR-BT and VMAT for localised head and neck cancer was performed at our institute [ 41 ]. Thirty-eight patients with tongue, floor of mouth and base of tongue cancer treated with interstitial BT were selected for the analysis.…”

“…This margin varies between 2 and 10 mm. However, there are studies in which the same target volume was used for BT and EBRT techniques [ 27 , 29 , 30 , 32 , 41 , 42 ]. It follows that the benefits of BT were underestimated in these studies and that the dosimetric values would have been more favourable towards BT if a larger volume (CTV + margin) had been used for EBRT planning.…”

Adjuvant interstitial three-dimensional pulse-dose-rate-brachytherapy for lip squamous cell carcinoma after surgical resection

“…Even though interstitial brachytherapy is invasive, this irradiation technique seems to be favorable for patients with lip cancer [22]. Due to brachytherapy dosimetric advantages and high conformity, it is eligible for local treatment [24,25,26].…”

Dosimetric comparison of two different applicators and rectal retraction methods used in inverse optimization-based intracavitary brachytherapy for cervical cancer

“…In radiation therapy (RT), local control and normal tissue complication probability is related to dose of radiation delivered to the target volume and organs at risk (OARs), respectively [5]. Dosimetric characteristics of IGBT makes it possible to deliver an ablative dose to the target volume while sparing surrounding OARs due to the steep dose gradient, which is not safely feasible with external beam radiotherapy (EBRT) techniques alone [6,7]. Therefore, IGBT has re-cently formed an integral part of the RT and it has been introduced to improve treatment outcomes in LACC [8,9,10,11,12,13].…”