5-aminolevulinic enhanced brain lesions mimic glioblastoma: A case report and literature review

Abstract

Rationale: Glioblastoma multiforme (GBM) is a highly malignant primary brain tumor for which maximal tumor resection plays an important role in the treatment strategy. 5-aminolevulinic (5-ALA) is a powerful tool in fluorescence-guided surgery for GBM. However, 5-ALA- enhancing lesion can also be observed with different etiologies.

Patients concerns: Three cases of 5-ALA-enhancing lesions with etiologies different from glioma.

Diagnoses: The final diagnosis was abscess in 1 patient and diffuse large B-cell in the other 2 patients.

Interventions: Three patients received 5-aminolevulinic acid-guided tumor resection under microscope with intraoperative neuromonitoring.

Outcomes: All of our patients showed improvement or stable neurological function outcomes. The final pathology revealed etiologies different from GBM.

Lessons: The 5-aminolevulinic acid fluorescence-guided surgery has demonstrated its maximal extent of resection and safety profile in patients with high-grade glioma. Non-glioma etiologies may also mimic GBM in 5-ALA-guided surgeries. Therefore, patient history taking and consideration of brain images are necessary for the interpretation of 5-ALA-enhanced lesions.

Figure 1.

(A) Patient 1 preoperative images. T1-weighted magnetic resonance with contrast image disclosed right parietal intra-axial ring-enhancing lesion with perifocal edema. (B) Patient 1 intraoperative image under blue-400 filter revealed strong 5-ALA-enhanced lesion. (C) Patient 1 pathological report revealed vascular proliferation, perivascular lymphoplasmacytic cuffing, abscess formation, and peri-meningeal fibrosis with focal granulation tissue formation, as assessed by hematoxylin and eosin staining. 5-ALA = 5-aminolevulinic.

Figure 2.

(A) Patient 2 preoperative image. T1-weighted magnetic resonance with contrast image disclosed heterogeneously enhanced lesion over corpus callosum and left basal ganglion with perifocal edema. (B) Patient 2 pathology report revealed cerebral tissues with perivascular and diffuse infiltration of large atypical lymphoid cells with nuclear pleomorphism, vesicular nuclei, prominent nucleoli, and brisk mitotic activity. Hematoxylin and eosin staining demonstrated diffuse large B-cell lymphoma of non-GC type.

Figure 3.

(A) Patient 3 preoperative image. T1-weighted magnetic resonance with contrast image revealed a vivid enhancing lesion over right frontal-parietal area. (B) Intraoperative microscopic view under blue-400 filter revealed strong 5-ALA-enhanced lesion. (C) Immunostaining with CD20 demonstrating tumor cells with a B-cell immune phenotype. 5-ALA = 5-aminolevulinic.