{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,11]],"date-time":"2026-10-11T03:35:12Z","timestamp":1791689712074,"version":"4.3.4"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,19]],"date-time":"2024-04-19T00:00:00Z","timestamp":1713484800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Provincial Secretariat for Higher Education and Scientific Research, Autonomous Province of Vojvodina, Republic of Serbia","award":["142-451-3006\/2023-01"],"award-info":[{"award-number":["142-451-3006\/2023-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Differentiating between a high-grade glioma (HGG) and solitary cerebral metastasis presents a challenge when using standard magnetic resonance imaging (MRI) alone. Magnetic resonance spectroscopy (MRS), an advanced MRI technique, may assist in resolving this diagnostic dilemma. N-acetylaspartate (NAA), an amino acid found uniquely in the central nervous system and in high concentrations in neurons, typically suggests HGG over metastatic lesions in spectra from ring-enhancing lesions. This study investigates exceptions to this norm. Materials and Methods: We conducted an MRS study on 49 histologically confirmed and previously untreated patients with brain metastases, employing single-voxel (SVS) techniques with short and long echo times, as well as magnetic resonance spectroscopic imaging (MRSI). Results: In our cohort, 44 out of 49 (90%) patients demonstrated a typical MR spectroscopic profile consistent with secondary deposits: a Cho peak, very low or absent Cr, absence of NAA, and the presence of lipids. A peak at approximately 2 ppm, termed the \u201cNAA-like peak\u201d, was present in spectra obtained with both short and long echo times. Among the MRS data from 49 individuals, we observed a peak at 2.0 ppm in five brain metastases from mucinous carcinoma of the breast, mucinous non-small-cell lung adenocarcinoma, two metastatic melanomas, and one metastatic non-small-cell lung cancer. Pathohistological verification of mucin in two of these five cases suggested this peak likely represents N-acetyl glycoproteins, indicative of mucin expression in cancer cells. Conclusions: The identification of a prominent peak at 2.0 ppm could be a valuable diagnostic marker for distinguishing single ring-enhancing lesions, potentially associated with mucin-expressing metastases, offering a new avenue for diagnostic specificity in challenging cases.<\/jats:p>","DOI":"10.3390\/medicina60040662","type":"journal-article","created":{"date-parts":[[2024,4,19]],"date-time":"2024-04-19T08:44:31Z","timestamp":1713516271000},"page":"662","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Peak Resembling N-acetylaspartate (NAA) on Magnetic Resonance Spectroscopy of Brain Metastases"],"prefix":"10.3390","volume":"60","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2303-7979","authenticated-orcid":false,"given":"Jelena","family":"Ostojic","sequence":"first","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6007-7072","authenticated-orcid":false,"given":"Dusko","family":"Kozic","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milana","family":"Panjkovic","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biljana","family":"Georgievski-Brkic","sequence":"additional","affiliation":[{"name":"Special Hospital for Cerebrovascular Diseases \u201cSveti Sava\u201d, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dusan","family":"Dragicevic","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5278-6194","authenticated-orcid":false,"given":"Aleksandra","family":"Lovrenski","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9701-5484","authenticated-orcid":false,"given":"Jasmina","family":"Boban","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University in Novi Sad, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1007\/s00234-016-1642-9","article-title":"Optimal differentiation of high- and low-grade glioma and metastasis: A meta-analysis of perfusion, diffusion, and spectroscopy metrics","volume":"58","author":"Usinskiene","year":"2016","journal-title":"Neuroradiology"},{"key":"ref_2","first-page":"17","article-title":"The Role of Advanced Imaging in Brain Metastases","volume":"30","author":"Brown","year":"2019","journal-title":"Neurosurg. 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