Locoregional recurrences after post-operative volumetric modulated arc radiotherapy (VMAT) in oral cavity cancers in a resource constrained setting: experience and lessons learned

Abstract

Cite this article as: Chakraborty S, Patil VM, Babu S, Muttath G, Thiagarajan SK. Locoregional recurrences after post-operative volumetric modulated arc radiotherapy (VMAT) in oral cavity cancers in a resource constrained setting: experience and lessons learned. Br J Radiol 2015;88:20140795. FULL PAPER Locoregional recurrences after post-operative volumetric modulated arc radiotherapy (VMAT) in oral cavity cancers in a resource constrained setting: experience and lessons learned Results: 75 patients with a median follow-up of 24 months were analysed. 41 (55%) patients had oral tongue cancers and 52 (69%) of the patients had Stage IVA cancers. The 2-year locoregional recurrence-free survival, diseasefree survival and overall survival were 88.9%, 82.1% and 80.5%, respectively. With a median time to failure of 6.5 months, five infield and three outfield failures were identified. Conclusion: A relatively low rate of outfield failure and lack of marginal failure attests to the efficacy of VMAT in such patients. Modifications to our existing target delineation policy have been proposed. Advances in knowledge: The use of standardized target delineation methods allows safe use of VMAT IMRT even in resource-constrained settings.

Definitive‐intent intensity‐modulated radiation therapy provides similar outcomes to those previously published for definitive‐intent three‐dimensional conformal radiation therapy in dogs with primary brain tumors: A multi‐institutional retrospective study

“…However, the increasing conformity of IMRT calls for accuratetarget delineation and confirmation of daily patient positioning. Errors in positioning and inaccuracies or misconceptions of the extent of tumor infiltration have the potential to increase the risk of a geographic miss compared to less conformal 3DCRT [6][7] . Accurate target contouring is especially important, as canine meningiomas have been reported to be more invasive than their human counterparts 8 .Additional concerns arise with the use of IMRT.…”

The Hippocampus: A New Organ at Risk for Postoperative Radiation Therapy for Bucco-alveolar Cancer? A Dosimetric and Biological Analysis

“…The proximity of the infratemporal fossa (ITF) to the hippocampus ( Figure-1a) and the fact that the ITF is routinely included in the clinical target volume (CTV) in patients with buccoalveolar carcinoma. (24)(25)(26) formed the basis of our study.…”

“…The high-risk CTV (HRCTV) encompassed pre-operative gross disease, operative bed, flap with adequate margin including surgical clips/post-operative changes, masticator space, ITF and involved nodal levels. (25,29) The protocol for inclusion of neck-nodal levels has been previously reported. (30) The low-risk CTV (LRCTV) included uninvolved at-risk nodal levels, ipsilateral nodal levels IA-V and contralateral levels IB-IV for node-positive neck and ipsilateral nodal levels IA-IV for the node-negative neck.…”

“…The proximity of the infratemporal fossa (ITF) to the hippocampus ( Fig 1 a) and the fact that the ITF is routinely included in the clinical target volume (CTV) in patients with bucco-alveolar carcinoma 24 , 25 , 26 formed the basis of this study.

Figure 1 (a) Axial section of planning computed tomography scan showing the proximity of the infratemporal fossa to the ipsilateral hippocampus.

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Intensity-modulated proton therapy decreases dose to organs at risk in low-grade glioma patients: results of a multicentric in silico ROCOCO trial

“…There has been an impressive progress in recent photonbased radiotherapy techniques, moving from 3D conformal radiotherapy (3D-CRT) to intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and tomotherapy (TOMO), delivering high radiation dose to the target and low doses to surrounding organs at risk (OARs) [8]. Examples of this progress are the RTOG 0933 phase 2 clinical study on conformal hippocampus sparing whole brain radiotherapy showing a preservation of memory and quality of life, and the ongoing trial on hippocampus-sparing prophylactic cranial irradiation using VMAT, IMRT or TOMO (NCT01780675) [9].…”