see Intracranial Metastases Classification
Brain metastases from cancer of unknown primary site.
From different cancers.
For example:
EGFR-Mutant Non-Small-Cell Lung Cancer Intracranial Metastases
Bladder cancer intracranial metastases.
Brain metastases from ovarian cancer.
Brain Metastases from Endometrial Cancer.
Colorectal cancer (CRC) infrequently causes brain metastases (BM) (1.2%) 1).
The majority of brain metastases originate from primary cancers in the lung (40–50%) or breast (15–25%), or from melanoma (5–20%) 2)
They are common in elderly population and mostly due to primary lung. Adenocarcinoma was the most common histology of primary. Majority of lesions has been observed at parietal lobe 3).