Pulmonary meningioma: false-positive positron emission tomography for malignant pulmonary nodules

Area of Science:

• Pulmonology
• Neuropathology
• Oncology

Background:

• Intraparenchymal lung tumors require accurate diagnosis to differentiate benign from malignant conditions.
• Positron emission tomography (PET) using fluorodeoxyglucose (FDG) is a key imaging modality for evaluating pulmonary nodules.
• Meningiomas are typically intracranial tumors arising from meningothelial cells.

Observation:

• A solitary asymptomatic pulmonary nodule demonstrated increased FDG uptake on PET scans.
• Histopathologic and immunophenotypic analysis revealed characteristics consistent with an intracranial meningioma.
• No evidence of a central nervous system tumor was found, suggesting a primary pulmonary origin.

Findings:

• The resected pulmonary nodule was diagnosed as a benign psammomatous meningioma.
• This case represents a rare instance of a primary intraparenchymal lung tumor with meningioma-like features.
• The tumor's presentation mimicked a malignant pulmonary nodule on initial imaging.

Implications:

• This finding underscores the importance of comprehensive histopathological evaluation for pulmonary nodules, even with atypical imaging findings.
• Such cases can lead to false-positive results in PET scans, potentially complicating the diagnostic pathway for lung nodules.
• Awareness of rare tumor presentations, like pulmonary meningioma, is crucial for accurate diagnosis and patient management.