A 74-year-old woman with a history of a seizure disorder had been followed for several years with a stable and unsymptomatic left parasagittal dural-based brain tumor presumed to be a benign meningioma. Recently, though, the lesion increased in size and hemorrhaged, leaving her significantly paretic on the right side. Neurosurgery thereupon performed a craniotomy for tumor removal. Intraoperative frozen section diagnosis was meningioma. But, upon receipt of the permanent sections, I was impressed by the staghorn vessels at low power and hemangiopericytoma immediately came to mind.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-n84o_kgOlDwB2l9DnRMZCfX41ej56Cq80XMQnKVaEps2nSIN7G6wgq2zMdNOhp3uHlMBwHsljbADAiLCmrMtt5PzbzIJSutZbUMVue9zfzfhuN3gQnYEor8EKGTX4706JSBC37yhI13f/s320/2.TIF) |
Staghorn vessels prominent in region below dot marks |
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhPS6_krzACsbs5cLQo-mSR1DBYdPwvPf3HPqDqQgqN9u8ZllkDHhA1LKSP8W-Tj_alcO9hXZQoSM6bxAyD08oalgb7hbpwH-PVlKhfuJcu9nHjLsDpEfvvFgmDcVrhmFc1_8qbABvMPcyC/s320/3.TIF) |
Psammoma body consistent with original impression that this was simply a meningioma |
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjbmUG5w99l8G1sCBBRzV2FS-Q-tITnE0RDIlCrrX1Z5kEobtd-HBvcNnKCXXn3YSqAPWi25P63FJEnyMJ2vT8zFj98cpmjEYBndgIKqAn1Z2yCBWYDDGD4MAt6L3xiUTd1iYEyUzO-ulU3/s320/5.TIF) |
Whirled architecture consistent with meningioma |
I was obviously dealing with a meningioma, but something else was going on in that area featuring the staghorn vessels. This region exhibited a different histomorphology:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEioVtR86J5GFJiZa90HgplAsqUUzPBdugk4Uu6EF9GKbRGQdnBfBLvFCQA9xSDSqPSzth3a8YlmhKS8zqrLH9yjFHlc-4TXqTZanQZkYAafsw8nzFjdkb99hlWuxr7zM0WBa2BeL2w-vAFn/s320/6.TIF) |
Clear cells |
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj1-n8aIXqW1Cde31bKePHQr6IDR1LBJBeFeOks52_2fvxlWfm4el0os6EbEM0-UQrSRMDdEvJBU-Kh4VTgB-nCNbSUmedjxeijw4blAHc-gY7E9XobJ5OdPtE3dMndWKqKeU44W7_ghYxZ/s320/7.TIF) |
High-power view of clear cell portion of specimen |
This dual morphology puzzled me. I then discovered that back in 2003 the patient had undergone a radical nephrectomy for renal cell carcinoma. Surgical margins of the nephrectomy specimen were free of tumor. I retrieved the 2003 nephrectomy specimen, which looked quite similar to the clear cell portion of the brain tumor:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhwdjidia0gmJ5OwTIFRGrR7VTgZkoKVT-H6ow9eUuAvfNGhW1MXYXUwjpDunpITrXk45ia5vf4adlueF5MHmpFOuGgYJnOuxe6AbOhuD8MIXmiYsN-6xD-HtWN-SsYk1kcXpyFdug2_IK3/s320/2003+renal+cell+carcinoma.TIF) |
Nephrectomy specimen from 2003 showing renal cell carcinoma, clear cell type |
I thereupon went back to the brain tumor specimen and did some immunohistochemical stains, including RCC for suspected renal cell carcinoma metastasis:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEitKUO_4xQpW4JsKyaLNV6EQTBgiivn6y_eOzTDn3G-DFo000G9GANogV6kOO7YZIQtP0wbAJbm3dc4uzL_gOmXacXeYFTA5vFrfZP1E0ZRhvls4oLJuT1iU4jxURqtzlYuOeMLI_DpRJZC/s320/RCC+IHC.TIF) |
Positive RCC Immunohistochemistry |
I had a case of renal cell carcinoma metastatic to a meningioma! Such a case had been reported in the literature before:
Han, HS, et al. Metastatic renal cell carcinoma in a meningioma: a case report. J Korean Med Sci. 2000 October 15 (5):593-597.
Here's case number two!
Follow-up: The patient received radiation to the tumor bed and is recovering.