Susceptibility-weighted imaging in malignant melanoma brain metastasis
- PMID: 30793419
- DOI: 10.1002/jmri.26692
Susceptibility-weighted imaging in malignant melanoma brain metastasis
Abstract
Background: The value of cerebral susceptibility-weighted imaging (SWI) in malignant melanoma (MM) patients remains controversial and the effect of melanin on SWI is not well understood.
Purpose: To systematically analyze the spectrum of intracerebral findings in MM brain metastases (BM) on SWI and to determine the diagnostic value of SWI.
Study type: Retrospective.
Population/subjects: In all, 100 patients with melanoma BM (69 having received radiotherapy [RT] and 31 RT-naïve) and a control group of 100 melanoma patients without BM were included. For detailed analysis of signal characteristics, 175 metastases were studied.
Field strength/sequence: Gradient echo SWI sequence at 1.5, 3.0, and 9.4 T.
Assessment: Signal characteristics from melanotic and amelanotic BMs on SWI with a focus on blooming artifacts were analyzed, as well as the presence and longitudinal dynamics of isolated SWI blooming artifacts in patients with and without BM.
Statistical tests: Chi-squared and Student's t-test were used for contingency table measures and group data of signal and clinical characteristics, respectively.
Results: Melanotic and amelanotic metastases did not show significant differences of SWI blooming artifacts (38% vs. 43%, P = 0.61). Most metastases without an initial SWI artifact developed a signal dropout during follow-up (80%; 65/81). Isolated SWI artifacts were detected more frequently in patients with BM (20 vs. 9, P = 0.03), of which the majority were found in patients who had received RT (17 vs. 3, P = 0.08). None of these isolated SWI blooming artifacts turned into overt metastases over time (median follow-up: 8.5 months). Similar findings persisted as remnants of successfully treated metastases (88%; 7/8).
Data conclusion: We conclude that SWI provides little additional diagnostic benefit over standard T1 -weighted imaging, as melanin content alone does not cause diagnostically relevant SWI blooming. Signal transition of SWI may rather indicate secondary phenomena like microbleeding and/or metal scavenging. Our results suggest that isolated SWI artifacts do not constitute vital tumor tissue but represent unspecific microbleedings, RT-related parenchymal changes or posttherapeutic remnants of former metastatic lesions.
Level of evidence: 3 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2019;50:1251-1259.
Keywords: brain metastasis; magnetic resonance imaging; melanoma; susceptibility weighted imaging.
© 2019 International Society for Magnetic Resonance in Medicine.
References
-
- Ajithkumar T, Parkinson C, Fife K, Corrie P, Jefferies S. Evolving treatment options for melanoma brain metastases. Lancet Oncol 2015;16:e486-497.
-
- Eggermont AM, Spatz A, Robert C. Cutaneous melanoma. Lancet 2014;383:816-827.
-
- Flanigan JC, Jilaveanu LB, Chiang VL, Kluger HM. Advances in therapy for melanoma brain metastases. Clin Dermatol 2013;31:264-281.
-
- Wolchok JD, Kluger H, Callahan MK, et al. Nivolumab plus ipilimumab in advanced melanoma. N Engl J Med 2013;369:122-133.
-
- Cohen JV, Tawbi H, Margolin KA, et al. Melanoma central nervous system metastases: Current approaches, challenges, and opportunities. Pigment Cell Melanoma Res 2016;29:627-642.
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