Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT02745548 |
Other study ID # |
HP-00069334 |
Secondary ID |
|
Status |
Recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
June 1, 2017 |
Est. completion date |
December 2027 |
Study information
Verified date |
May 2024 |
Source |
University of Maryland, Baltimore |
Contact |
Amit Sawant, PhD |
Phone |
410-706-5517 |
Email |
asawant[@]som.umaryland.edu |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
In order to better understand radiation-induced lung toxicity, the investigator proposes a
novel functional avoidance approach that incorporates central as well as peripheral BSS
segments in the treatment planning process in order to quantify and account for their
respective radiosensitivities. Specifically, the investigator proposes a systematic study
that involves acquiring pre- and post-SAbR high-resolution CT and SPECT V/Q scans from lung
cancer patients who receive radiotherapy, followed by auto-segmentation of the BSS elements
using virtual bronchoscopy.
Description:
Very few recent lung cancer therapies have had as positive an impact on public health as lung
SAbR. Lung SAbR involves the precise administration of very high, biologically potent doses
(54-70 Gy) in 3-5 fractions. The most recent update of the Radiation Therapy Oncology Group
(RTOG) 0236 Phase II multi-center lung SAbR trial showed 5-year primary tumor control >90% in
inoperable Stage I NSCLC patients with tumors ≤ 5cm. However, the use of such highly potent
doses puts patients at risk for collateral toxicity including radiation pneumonitis and
radiation injury to airways, causing stenosis, atelectasis and ultimately fibrosis. A review
of 35 early-stage NSCLC SAbR clinical studies found that the reported maximum values of Grade
≥3 toxicities were between 10-28%. In the RTOG 0236 trial, 17% patients presented Grade ≥3
toxicities. Furthermore, toxicity has been shown to increase dramatically for
centrally-located and/or larger (> 5cm) early-stage tumors. Due to these concerns, in current
clinical practice, the use of high-dose-per-fraction lung SAbR is routinely indicated only
for a small percentage (~3 - 4%) of the NSCLC population - inoperable, early-stage patients
with small, peripheral lesions. Inoperable patients with early-stage central and/or larger
tumors, higher stage and/or multiple lesions, and pulmonary oligometastases (metastatic
disease that is limited in number of lesions and sites) are either treated with conventional
radiotherapy and/or chemotherapy (~30 - 40% 5-year survival), or not treated (median survival
~1 year).
The segmented structures will be imported into a clinical radiotherapy treatment planning
system in order to calculate dose to individual BSS elements. Follow-up CT images and
follow-up SPECT V/Q scans will be used to characterize the radiosensitivity of these
structures and spatially map the potential radiation-induced loss of lung function.
Eventually, using this information, the investigator will investigate treatment planning
strategies that help limit radiation dose and consequent damage to BSS elements, thereby
reducing lung toxicity. The investigator hypothesizes that - Anatomically variable radiation
injury to the bronchial tree and pulmonary vasculature is an important determinant of
post-SAbR pulmonary toxicity and residual pulmonary function.