Tumor-to-tumor metastasis from hematopoietic neoplasms to meningiomas: report of two patients with significant cerebral edema.

BACKGROUND: Tumor-to-tumor metastasis is a rare, but well-reported, curiosity in which one type of primary neoplasm metastasizes to another primary tumor type within the same person. Often there are limited clinical consequences and the condition is an incidental finding identified only on microscopic examination of a resected specimen. OBJECTIVE: To report two examples of benign meningiomas in which metastatic tumor deposits from the patient's hematopoietic neoplasm to the meningioma caused significant peritumoral edema, necessitating semiemergent surgical resection. Clinical suspicion in both patients was an atypical or anaplastic meningioma due to the edema. RESULTS: One patient had multiple myeloma associated with extensive necrosis within his otherwise benign convexity meningioma; first diagnosis of his IgG, kappa-restricted plasma cell dyscrasia was made from this tumor-to-tumor meningioma specimen. Subsequent workup revealed systemic disease. The second patient carried a diagnosis of marginal zone lymphoma but then presented 5 years later with symptoms referable to a large dural-based mass with significant surrounding edema, prompting surgical removal. Dural marginal zone lymphoma was identified within epidural, intradural, and subdural spaces, in the same location as an underlying benign meningioma. CONCLUSIONS: Although rare, neurosurgeons should be aware of the entity of tumor-to-tumor metastasis as, in large series, meningiomas are the third most frequent recipient tumor type and pituitary adenomas, the fifth most frequent, probably reflecting their rich vascularity. In examples where the donor tumor type is a hematopoietic neoplasm, significant edema can be produced by the tumor-to-tumor metastasis.

Prevalence of intracranial aneurysms in first-degree relatives of patients with aneurysms.

OBJECT: A familial predisposition toward cerebral aneurysms has been previously described in patients with two or more affected family members. In the present study the familial incidence of unruptured intracranial aneurysms was studied in 96 patients with at least one first-degree relative (parent, sibling, or child) in whom a cerebral aneurysm was diagnosed. METHODS: All patients were between 20 and 70 years of age and underwent three-dimensional fast-spin echo magnetic resonance imaging. Sixty-one patients (63.5%) were women. The majority of patients (84%) were caucasian and the remainder were Hispanic (13%) or African-American (3%). No patient suffered a medical condition (excluding hypertension and smoking) known to be associated with cerebral aneurysm formation. In four patients at least one aneurysm was found (two harbored multiple aneurysms). Three of the four patients were women. Two of the patients were siblings. The estimated prevalence in first-degree relatives was 4.2% (95% confidence interval 1.2-10.1). Of note, the mean age in the current study population was 39 years. The authors of recent metaanalyses have suggested that the prevalence of nonfamilial aneurysms is approximately 2%, despite earlier reports in which higher figures were cited. CONCLUSIONS: The authors conclude that first-degree relatives of patients with aneurysms are at higher risk for harboring an intracranial aneurysm.