Helical tomotherapy of spinal chordomas: French Multicentric, retrospective study of a cohort of 30 cases

Maxime Bobin,Véronique Brouste,Christina Zacharatou,Marc-André Mahé,Loïc Feuvret,Stéphanie Hoppe,Paul Sargos,Guy Kantor,Bénédicte Henriques De Figueiredo,Albert Lisbona,Georges Noël,Amandine Halley,Louis Gras

doi:10.1186/s13014-017-0768-1

Abstract

PurposeTo evaluate the efficacy and toxicity of helical tomotherapy (HT) in the management of spine chordomas when proton therapy is unavailable or non-feasible.Methods and materialsBetween 2007 and 2013, 30 patients with biopsy-proven chordomas were treated by HT in five French institutions. Information regarding local control (LC), overall survival (OS), progression-free survival (PFS) and metastasis-free survival (MFS) was collected. Clinical efficacy, toxicity and treatment quality were evaluated.ResultsTwo-year actuarial LC, OS, PFS and MFS were 69.9%, 96.7%, 61.2% and 76.4%, respectively. HT treatments were well tolerated and no Grade 4–5 toxicities were observed. HT permitted the delivery of a mean dose of 68 Gy while respecting organ at risk (OAR) dose constraints, in particular in the spinal cord and cauda equina.ConclusionsThis multicentric, retrospective study demonstrated the feasibility of HT in the treatment of spine chordomas, in the absence of hadron therapy.

Highlights

Chordomas are rare cancers, representing 1–4% of primary bone cancers, with a global incidence of 8.4 in 10 million persons [1]
Helical tomotherapy (HT) permitted the delivery of a mean dose of 68 Gy while respecting organ at risk (OAR) dose constraints, in particular in the spinal cord and cauda equina
This multicentric, retrospective study demonstrated the feasibility of HT in the treatment of spine chordomas, in the absence of hadron therapy

Summary

Introduction

Chordomas are rare cancers, representing 1–4% of primary bone cancers, with a global incidence of 8.4 in 10 million persons [1]. Radical en bloc resection with healthy tissue margins is currently the preferred treatment as it delivers best local control (LC) rates. This procedure is rarely possible because of the proximity of the tumor to neurological structures (spinal cord, cauda equina, nerve roots) or infiltration in soft tissue and vasculo-nervous axis or digestive and urinary system vicinity [3]. High-dose radiation therapy (RT), in particular proton and carbon ion therapy, leads to an increase in LC of the disease [4,5,6] These techniques remain very costly and are not readily available. HT has shown, in our experience, dosimetric advantages to other forms of IMRT as it allows for steeper dose gradients at the border of the tumor than other radiation delivery techniques

Methods

Results

Conclusion