Tumor-to-tumor metastasis: breast carcinoma to meningioma.

Metastasis of breast carcinoma to meningioma is a rare phenomenon with relatively few reports in the literature, although it is the most common type of carcinoma-to-meningioma metastasis. Several factors have been implicated in the pathogenesis of these lesions, including the microenvironment and vascular network of the meningioma, expression of cell-cell adhesion molecules, local immunosuppression, and hormonal factors, including estrogen and progesterone, whose receptors have been well-characterized in these two tumor types. While histopathologic study is the cornerstone of diagnosis of these lesions, newer radiological modalities such as magnetic resonance spectroscopy and perfusion MRI have shown promise, particularly in screening patients at risk for developing these lesions.

Intrameningioma metastasis of breast carcinoma.

Tumor-to-tumor metastasis of breast carcinoma to meningioma is a rare phenomenon. It is likely underdiagnosed given the relatively high prevalence and comorbidity of these two primary tumor types, the lack of standardized methodologies for its diagnosis, and the tendency to obfuscate this lesion with simple meningioma or cerebral metastasis of breast carcinoma. Careful histopathologic study of the resected meningioma is the cornerstone of diagnosis of these lesions, although certain conventional radiological features along with specialized modalities may clue the diagnosis.