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DE-CT in Lung Cancer Proton Therapy (DE-CT)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02844140
Recruitment Status : Withdrawn
First Posted : July 26, 2016
Last Update Posted : April 14, 2017
Information provided by (Responsible Party):
Maastricht Radiation Oncology

Brief Summary:
Dose distribution calculations for proton therapy are more accurate when based on DE-CT than on SE-CT. It is however unclear what the quantitative benefit of repeated DE-CT calculations is for lung cancer patients.

Condition or disease Intervention/treatment Phase
Non Small Cell Lung Cancer Procedure: DE-CT's and SE-CT Not Applicable

Detailed Description:

In order to calculate the dose distribution of protons adequately, accurate estimations of the stopping power ratio (SPR) medium to water, are required. Using a conversion from single energy CT (SE-CT) images results in an uncertainty in the SPR of at least 3-4%. This uncertainty results in in the use of larger margins around the clinical target volume (CTV) and hence more dose to the organs at risk (OAR). It also effects in the conservative use of beam directions, which are often sub-optimal, to avoid irradiating normal tissues.

Dual energy CT (DE-CT) improves the accuracy of the SPR and therefore the proton range estimation.

An evaluation of the proton range for several tissues using SE-CT and DE-CT as input to Monte Carlo (MC) simulations showed on average improvements in range prediction from 0.1% to 2.1% when using DECT instead of SECT, but in several phantoms and also versus proton-CT, the errors on SE-CT based proton stopping power ratios are reported to be more than 7 %.

A limitation of these studies is that most of them were performed in phantoms. In the first clinical data set on five patients with base of skull tumours, it was reported that although the SPR estimation was indeed better for DE-CT than for SE-CT, its clinical relevance was unclear. However, in the same study, phantom measurements showed a large uncertainty of the SPR in the lung. This is due to the large heterogeneity of the lungs and the huge difference in the density of the lungs compared to the mediastinum, the tumour and the chest cavity.

It is therefore important to study the SPR differences of SE-CT compared to DE-CT in lung cancer patients and the impact on the dose distribution especially in the context of adaptive radiotherapy. As during the course of concurrent chemotherapy and radiotherapy, which is the standard treatment in the majority of stage III lung cancer patients, important anatomical changes may occur, it is also of clinical relevance to determine the influence of repeated dose calculations on DE-CT.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 0 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: DE-CT vs. SE-CT as Optimal Imaging During Treatment for Adaptive Proton Therapy in Stage III Non Small Cell Lung Cancer (NSCLC)
Study Start Date : September 2016
Estimated Primary Completion Date : September 2017
Estimated Study Completion Date : December 2017

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Scans
Patients included in the trial will receive DE-CT in stead of SE-CT's.
Procedure: DE-CT's and SE-CT
Patients included in the trial will receive 3 extra DE-CT's and 3 extra SE-CT's

Primary Outcome Measures :
  1. Dose distribution on the CTV (measured in Gy) [ Time Frame: Measured during 2nd and 4th week of radiation treatment ]
    Dose distribution on the CTV (clinical target volume) of the tumour and the lymph nodes of DE-CT vs. SE-CT

  2. Dose distribution on the OAR (measured in Gy) [ Time Frame: Measured during 2nd and 4th week of radiation treatment ]
    Dose distribution on the OAR (organs at risk), lungs, heart, aorta, pulmonary artery, superior vena cava, oesophagus, spinal cord, vertebral body, of DE-CT vs. SE-CT

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Histologically or cytologically confirmed locally advanced stage IIIA or III B (T0-4 N2-3M0) NSCLC, or M1 oligometastatic disease according to 7th TNM classification.
  • Scheduled to receive concurrent chemotherapy and radiotherapy to a dose of at least 60 Gy, as decided at the multidisciplinary tumour board
  • Able to give written informed consent
  • Able to have adequate contraception in woman with child bearing potential

Exclusion Criteria:

  • Not able to give written informed consent
  • Not able to comply with adequate contraception in woman with child bearing potential

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02844140

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MAASTRO clinic
Maastricht, Limburg, Netherlands, 6229 ET
Sponsors and Collaborators
Maastricht Radiation Oncology
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Principal Investigator: Dirk De Ruysscher, MD, PhD Maastro Clinic, The Netherlands
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Responsible Party: Maastricht Radiation Oncology Identifier: NCT02844140    
Other Study ID Numbers: DE-CT
First Posted: July 26, 2016    Key Record Dates
Last Update Posted: April 14, 2017
Last Verified: August 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Additional relevant MeSH terms:
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Lung Neoplasms
Carcinoma, Non-Small-Cell Lung
Respiratory Tract Neoplasms
Thoracic Neoplasms
Neoplasms by Site
Lung Diseases
Respiratory Tract Diseases
Carcinoma, Bronchogenic
Bronchial Neoplasms