Potential of adaptive radiotherapy to escalate the radiation dose in combined radiochemotherapy for locally advanced non-small cell lung cancer

Int J Radiat Oncol Biol Phys. 2011 Mar 1;79(3):901-8. doi: 10.1016/j.ijrobp.2010.04.050. Epub 2010 Aug 12.


Purpose: To evaluate the potential of adaptive radiotherapy (ART) for advanced-stage non-small cell lung cancer (NSCLC) in terms of lung sparing and dose escalation.

Methods and materials: In 13 patients with locally advanced NSCLC, weekly CT images were acquired during radio- (n=1) or radiochemotherapy (n=12) for simulation of ART. Three-dimensional (3D) conformal treatment plans were generated: conventionally fractionated doses of 66 Gy were prescribed to the planning target volume without elective lymph node irradiation (Plan_3D). Using a surface-based algorithm of deformable image registration, accumulated doses were calculated in the CT images acquired during the treatment course (Plan_4D). Field sizes were adapted to tumor shrinkage once in week 3 or 5 and twice in weeks 3 and 5.

Results: A continuous tumor regression of 1.2% per day resulted in a residual gross tumor volume (GTV) of 49%±15% after six weeks of treatment. No systematic differences between Plan_3D and Plan_4D were observed regarding doses to the GTV, lung, and spinal cord. Plan adaptation to tumor shrinkage resulted in significantly decreased lung doses without compromising GTV coverage: single-plan adaptation in Week 3 or 5 and twice-plan adaptation in Weeks 3 and 5 reduced the mean lung dose by 5.0%±4.4%, 5.6%±2.9% and 7.9%±4.8%, respectively. This lung sparing with twice ART allowed an iso-mean lung dose escalation of the GTV dose from 66.8 Gy±0.8 Gy to 73.6 Gy±3.8 Gy.

Conclusions: Adaptation of radiotherapy to continuous tumor shrinkage during the treatment course reduced doses to the lung, allowed significant dose escalation and has the potential of increased local control.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms*
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Carcinoma, Non-Small-Cell Lung / diagnostic imaging
  • Carcinoma, Non-Small-Cell Lung / drug therapy
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Carcinoma, Non-Small-Cell Lung / radiotherapy*
  • Cisplatin / administration & dosage
  • Combined Modality Therapy / methods
  • Dose Fractionation, Radiation
  • Etoposide / administration & dosage
  • Humans
  • Lung Neoplasms / diagnostic imaging
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / pathology*
  • Lung Neoplasms / radiotherapy*
  • Middle Aged
  • Organs at Risk / diagnostic imaging
  • Radiotherapy Planning, Computer-Assisted / methods
  • Radiotherapy, Conformal / methods*
  • Remission Induction
  • Spinal Cord / radiation effects
  • Statistics, Nonparametric
  • Tomography, X-Ray Computed
  • Tumor Burden / radiation effects
  • Vinblastine / administration & dosage
  • Vinblastine / analogs & derivatives
  • Vinorelbine


  • Vinblastine
  • Etoposide
  • Cisplatin
  • Vinorelbine