Case report of an unusual diagnosis of intracerebral hemorrhage (ICH) due to tumor to tumor metastasis of hemorrhagic renal cell carcinoma (RCC) to meningioma.

A 56 year old woman with history of hypertension, Renal Cell Carcinoma (RCC) of the left kidney status-post resection presented to the emergency department due to acute onset of right sided headache and dysarthria. Her vital signs were remarkable for blood pressure 182/89, and neurological exam for left lower facial weakness and dysarthria. Computerized tomography (CT) of the head showed 4.3x3.0x3.7cm mixed attenuation mass, with hyper-density centered in the inferior right frontal lobe extending into the basal ganglia and surrounding vasogenic edema causing 14mm right-to-left midline shift. Differential diagnosis included hypertensive ICH, new intra-tumor hemorrhage and RCC metastasis.

No vascular malformation was noted on CT with angiogram of the head.  Magnetic resonance imaging with and without contrast showed large heterogeneously enhancing extra-axial mass in the right basilar-frontal region with dural enhancement suspicious for a meningioma. CT of chest/abdomen/pelvis showed no evidence of RCC recurrence, however multiple pulmonary nodules suspicious for metastatic disease were identified. Due to significant mass effect, right fronto-temporal craniotomy for tumor resection was performed successfully. Pathological analysis showed sections of meningioma with good meningothelial differentiation intermixed with fragments of metastatic carcinoma with features of renal cell carcinoma.

Tumor to tumor metastasis is a rare entity described as the recipient tumor being a true neoplasm and the donor neoplasm a true metastasis. Meningioma have been described as the most common recipient of metastatic cells due to its high vascularity. Although rare, it is important to consider tumor to tumor metastasis in patients presenting with ICH and history of previous neoplasms. A body scan should be considered in these cases as patient management and prognosis may be affected based on metastasis load.