Qingsong Yang1, Zhen Wang1, Luguang Chen1, Yukun Chen1, Chao Ma1, Caixia fu2, Xu Yan3, Hui Liu3, and Jianping Lu1
1Radiology Department, Changhai Hospital, Shanghai, China, People's Republic of, 2Application Department, Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China, People's Republic of, 3MR Collaboration NE Asia, Siemens Healthcare, Shanghai, China, People's Republic of
Synopsis
Bone
metastasis is a leading cause of morbidity and mortality for patients with
metastatic prostate cancer. Early detection of bone metastasis plays a key role
in the assessment of treatment methods and prognosis. This study aims to
evaluate the diagnostic efficiency of readout-segmented whole body diffusion weighted
imaging in the detection of bone metastases for patients with newly diagnosed
high-risk or biochemical recurrent prostate cancer. The result shows that RESOLVE whole-body DWI has higher sensitivity,
specificity and accuracy in bone metastasis detection than bone
scintigraphy using 99mTc-MDP (BS).Introduction and purpose
Bone metastasis is a leading cause of morbidity and
mortality for patients with metastatic prostate cancer. Early detection of bone
metastasis plays a key role in the assessment of treatment methods and
prognosis. Although currently bone scintigraphy serves as the standard method to
detect bone metastasis, whole-body MRI has been shown to be more sensitive. However,
research on homogeneous tumor entities by using MRI is still uncommon. This
study aims to evaluate the diagnostic efficiency of readout-segmented whole
body diffusion weighted imaging and bone scintigraphy using 99mTc-MDP (BS) in
the detection of bone metastases for patients with newly diagnosed high-risk or
biochemical recurrent prostate cancer.
Materials and methods
From June 2014 to December
2014, 63 consecutive patients with newly diagnosed high-risk or biochemically
recurrent prostate cancer were recruited for this prospective study. All
patients underwent both readout-segmented EPI [1] for whole body diffusion
weighted imaging (RESOLVE WB-DWI) on a 3T MRI scanner (MAGNETOM Skyra, Siemens
Healthcare, Erlangen, Germany) and bone scintigraphy completed with target
scan. RESOLVE WB-DWI used the following parameters: TR/TE = 7500/68ms, FOV =
430 x 340 mm2, scan matrix = 176 x 176, slice thickness = 5mm, b =
0, 800 s/mm2, diffusion mode = 3D diagonal, 4 or 5 steps (depending
on the patient’s height) with coverage from head to pelvis, total scan time
=~21 mins. The MRI target scans included T2WI (STIR), T1WI and contrast
enhanced T1WI if suspected lesions were found. Both examinations were completed
within 10 days after the patients were included in this study. Patient- and
lesion-based analyses were each performed by two experienced radiologists. All
patients received a follow up exam after 4-6 months with RESOLVE WB-DWI or BS which
were considered as the best valuable comparator (BVC) to evaluate the WB-DWI
and BS diagnosis for sensitivity, specificity and accuracy. The chi-square test
was used for the significant differential analysis.
Results
Based on the BVC, 20
patients (32%) had bone metastasis. In patient-based analysis, RESOLVE WB-DWI showed 18 true-positive findings while BS had
only 12 true-positive findings. Three patients were diagnosed with uncountable
bone metastases. In these patients, DWI showed more bone metastases than
BS. When using lesion-based analysis, these patients were analyzed separately. RESOLVE
WB-DWI showed earlier detection of bone metastasis
than BS, as demonstrated in figure 1. For the 27 bone metastasis lesions which could
be verified, RESOLVE WB-DWI was able to show 25
true-positive lesions and BS showed 16 true-positive lesions. The sensitivity, specificity,
and accuracy of WB-DWI and BS for detecting bone metastases based on patients were
90.00% and 60.00%, 97.50% and 80.00%, and 95.00% and 73.33%, respectively
(p<0.05). The sensitivity, specificity, and the accuracy of WB-DWI and BS
for detecting bone metastases based on lesions were 92.59% and 59.26%, 97.78%
and 77.78%, 95.83% and 70.83% , respectively (p<0.05).
Conclusions
RESOLVE
whole-body DWI shows higher sensitivity, specificity and accuracy than BS in bone
metastasis detection, and is capable of early detection and discovers
more bone metastases lesions caused by prostate cancer.
Acknowledgements
No acknowledgement found.References
[1] DA Porter et.al., MRM, 62:468-475 (2009)