A comparison of dose distributions in gross tumor volume between boron neutron capture therapy alone and combined boron neutron capture therapy plus intensity modulation radiation therapy for head and neck cancer

PLoS One. 2019 Apr 4;14(4):e0210626. doi: 10.1371/journal.pone.0210626. eCollection 2019.

Abstract

Nine patients with recurrent head and neck (H&N) cancer received boron neutron capture therapy (BNCT) in one fraction at the Tsing-Hua Open pool reactor (THOR) utilizing the THORplan treatment planning system (TPS). The aims of the present study were to evaluate the use of intensity modulated radiation therapy (IMRT) of 45 Gy in 20 fractions to compensate for the dose heterogeneity in gross tumor volume observed with single-fraction BNCT with mean prescription dose 19 Gy (w), and to evaluate planning quality indices of simulated BNCT+IMRT versus single-fraction BNCT alone. All IMRT plans were generated using the Eclipse TPS which employs the analytical anisotropic algorithm. The conformity index for the gross tumor volume (GTV) was better for the BNCT+IMRT plan than for the BNCT-alone plan (p = 0.003). In addition, the BNCT+IMRT plan provided significantly better homogeneity in the GTV (p = 0.03). The cold spots in inhomogeneous dose distribution in the BNCT plan may be a key factor for H&N cancer recurrence. Our results suggest that single-fraction BNCT combined with compensated multi-fraction IMRT improves treatment homogeneity and conformity than single-fraction BNCT alone, especially for tumor volumes >100 cm3, and possibly increases local tumor control.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Boron Neutron Capture Therapy*
  • Combined Modality Therapy / methods
  • Dose Fractionation, Radiation
  • Feasibility Studies
  • Head and Neck Neoplasms / diagnostic imaging
  • Head and Neck Neoplasms / radiotherapy*
  • Humans
  • Neoplasm Recurrence, Local / diagnostic imaging
  • Neoplasm Recurrence, Local / radiotherapy*
  • Radiotherapy Planning, Computer-Assisted / methods*
  • Radiotherapy, Intensity-Modulated*
  • Tomography, X-Ray Computed
  • Tumor Burden / radiation effects

Grants and funding

The first authors are grateful for financial support provided by grants obtained from Taipei Veterans General Hospital (No: V106A-016, https://www.vghtpe.gov.tw/Index.action). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.