Clinical History:

This 55-year-old man presented with the acute onset of left sided headache and mild right leg paresis. On CT scan a focal area of hemorrhage was seen near the gray white junction in the mid left frontal area. There was a questionable lesion in the right parietal lobe, but this was not well defined. It was decided to evacuate the lesion because of the mild mass effect and symptoms.

Image 8.1:

This T1 weighted post-contrast MRI scan in coronal view demonstrates the lesion. The mass lesion is brightly enhancing and could represent either blood or a neoplasm.

Image 8.2:

This microscopic section shows the cellular portion of the lesion evacuated and sent to surgical pathology.

The tumor cells are only mildly pleomorphic with clear cytoplasm. The lesion was well demarcated from the surrounding brain tissue.

Further history:

On questioning, the patient admitted to noting some blood-tinged urine in the weeks prior to his admission. He did not have any dysuria or urgency. A CT scan of the abdomen revealed a large mass in the right kidney.

Image 8.3:

This microscopic section of the brain is from another individual with the same disease. There is a well circumscribed hemorrhagic lesion in the right occipital lobe with some surrounding edema. What tumors commonly metastasize to brain?

Lung carcinoma, breast carcinoma, renal cell carcinoma, and melanoma.

Answers:

1. What are the possible etiologies for this lesion? What would be your follow-up after the discovery of the lesion?

Primary or metastatic tumor are possible etiologies. Follow-up consists of a more thorough exam and history to see if there is a primary tumor elsewhere in the body. Special stains can be done on the biopsy tissue to discern whether it is primary or metastatic. In general, well circumscribed tumors in brain are metastatic. The pattern of clear cells would suggest renal cell carcinoma.

2. What is the most likely diagnosis which explains both lesions? What is the treatment?

A renal cell carcinoma is the most likely diagnosis. Surgical removal of the kidney and a search for possible other metastatic sites is indicated. Over half of cases of metastases to the brain prove to have a lung primary. In women, breast cancer can metastasize to the brain. The neoplasm that is most likely to go to the brain when metastatic is melanoma.