[1694] Metastatic Carcinomas Presenting as Dural-Based Masses Mimicking Primary Intracranial Neoplasia

NM Savage, CH Alleyne, R Figueroa, S Sharma. Medical College of Georgia, Augusta, GA

Background: Clinical presentation with dural-based metastasis mimicking meningiomas is rare and described mostly as case reports from diverse primary locations. Proposed pathways include vascular spread and direct extension from calvarial or brain metastases.
Design: We retrospectively reviewed 6 cases with resection of dural-based metastatic carcinomas; five were clinically suspected to be meningiomas and one superficial glioblastoma.
Results: Patients' ages ranged from 59 to 80 years. MRIs showed extra-axial dural-based masses with contiguous but not primary brain involvement. The histopathologic and immunohistochemical diagnoses are tabulated. All primary sites were confirmed by subsequent clinical and radiologic evaluation except one case with immunoprofile for colorectal cancer where workup has yet to reveal a primary tumor.

Features of Dural-Based Metastases

Age/Sex	Location	Radiology Impression	Immunoprofile	Path Proposed Primary	Confirmed Primary	Mode of Primary Confirmation
78/M	Frontal, temporal, & parietal	Multiple meningiomatosis	CK20+, PSA+, CK7-	Prostate	Prostate	Chart review; Previous outside diagnosis
75/M	L parietal	Meningioma	Pankeratin+, PSA+, CK7-, CK20-, TTF1-, CDX2-	Prostate	Prostate	CT showing enlarged prostate & bladder invasion
59/F	L frontal	Meningioma or metastasis	Pankeratin+, CK7+, CK20-, TTF1-, CDX2-, ER-, PR-	Breast	Breast	Subsequent breast biopsy showing invasive ductal carcinoma
80/M	R parieto-occipital	Meningioma	Pankeratin+, CK7+, TTF1+, chromogranin+, CK20-, CDX2-	Lung	Lung	CT showing lung mass with hepatic & adrenal metastases
71/F	L frontal	Meningioma or metastasis	CK20+, CK19+, CDX2+, CK7-, TTF1-	Colorectal	?	N/A
59/M	R parietal	GBM involving dura	CK7+, CK19+, CK20-, TTF1-, CDX2-, PSA-	Lung, upper GI, pancreatico-biliary, or head & neck	Lung	PET showing lung mass

Conclusions: It is important for Neurosurgeons and Neuropathologists to be aware that carcinomas of diverse primary sites, including prostate, can present with dural-based masses radiologically mimicking meningiomas; therefore the surgery type can be suitably modified based on frozen section diagnosis. Moreover, a judicious combination of a screening immunohistochemical panel in conjunction with relatively specific transcription factors and hormone receptors can determine the primary tumor site with reasonable precision and guide oncologic therapy.
Category: Neuropathology

Tuesday, March 23, 2010 1:00 PM

Poster Session IV # 234, Tuesday Afternoon