Hyun Su Kim1 and Young Cheol Yoon1
1Radiology, Samsung medical center, Seoul, Korea, Republic of
Synopsis
The
presence of the epidermal growth factor receptor (EGFR) gene mutation is associated
with a high rate of distant metastasis and poor prognosis in patients with non-small
cell lung cancer (NSCLC). EGFR signaling acts as mediator of bone metastasis by
increasing tumor cell proliferation and promotes synthesis and secretion of
numerous angiogenic growth factors. We propose that metastatic bone lesions
with and without the EGFR mutation in primary NSCLC have different perfusion
profiles and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters
can reveal the differences.
Purpose
To
compare dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters between metastatic bone lesions with and without the
epidermal growth factor receptor (EGFR) gene mutation in consecutive patients with primary non-small cell lung cancer (NSCLC).Materials and methods
Forty-seven
patients with NSCLC and a confirmed EGFR mutation status (21, EGFR
mutation-positive; 26, EGFR mutation-negative), who underwent DCE-MRI for bone
metastases between November 2012 and March 2016, were included in this
IRB-approved study. Two independent radiologists performed analysis of extravasation
rate (Ktrans), reflux rate (kep), and the volume fraction
of the extravascular extracellular matrix (ve) using image-processing
software. Intergroup comparisons of the mean measured parameters were performed
using the Mann-Whitney U test. Interobserver agreement was calculated using the
intraclass correlation coefficient. Results
Analysis
revealed a high level of agreement between the two reviewers for all three
parameters (0.95 for Ktrans, 0.97 for kep, and 0.91 for ve).
Ktrans was significantly higher in the EGFR mutation-positive group
(P = 0.0389 for reviewer 1; 0.0315
for reviewer 2). kep was also higher in the EGFR mutation-positive
group, but showed statistical significance only in the evaluation performed by one
reviewer (P = 0.0478 for reviewer 2;
0.0583 for reviewer 1). No significant difference was observed in ve
(P = 0.8725 for reviewer 1; 0.8894
for reviewer 2).Conclusion
Our
study result has shown a significantly higher value of Ktrans in
metastatic bone lesions of EGFR mutation-positive primary lung cancer than in those
of EGFR mutation-negative primary lung cancer. A similar tendency was
demonstrated for kep on intergroup comparisons. These results may
reflect the histologic characteristic of bone metastasis from EGFR
mutation-positive lung cancer related to an increased angiogenic activity. The
findings may also form the basis for the possible use of DCE-MRI parameters for
evaluating treatment response in these lesions in future studies.Acknowledgements
No acknowledgement found.References
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3. Lu X, Kang Y. Epidermal growth factor signalling and bone metastasis. Br J Cancer 2010;102(3):457-461.
4. De Luca A, Carotenuto A, Rachiglio A, et al. The role of the EGFR signaling in tumor microenvironment. J Cell Physiol 2008;214(3):559-567.