Cerebral metastasis from MPM is classically haemorrhagic. The clinical characteristics differ depending on the CNS area involved, with the cerebral cortex, cerebellum, intracranial meninges, and spinal cord being the most commonly involved regions, and the midbrain, pons, or brainstem being less common (10). Perineural spread, leptomeningeal carcinomatosis, and most commonly haematogenous spread leading to parenchymal deposits are all possible mechanisms for CNS metastases (11).
The histologic appearance of MPM brain metastases may be comparable to glioblastoma multiforme (12). There are three histological kinds of MPM: sarcomatous, epithelial, and biphasic (2). Patients with sarcomatous histology have the poorest prognosis, and conventional treatments, such as surgery or chemotherapy are ineffective (13). According to the existing research, in one review study 11% of patients with cerebral metastases exhibited histological differences from the initial tumour indicating histological differentiation into more aggressive histological subtype (10).
CT is the first line imaging modality for patients with new neurological impairments (14). Acute haemorrhagic metastases to the brain appear hyperdense on non-contrast CT and are surrounded by varying vasogenic oedema (15). Contrast enhanced CT and MRI have higher sensitivity demonstrating T1WI hyperintensity, depending on the age of haemorrhage associated with diffusion restriction and peripheral enhancement on contrast administration (15). T2*-weighted GRE MRI is a sensitive tool for early detection of metastases displaying haemorrhagic changes (16).
Although MPM with brain metastasis is considered a fatal disease (17), most patients with this stage are discharged without therapy or with simply anti-oedema medication (18). Other treatment options include resection, whole- brain radiation, stereotactic radiotherapy, systemic corticosteroids, intrathecal or systemic chemotherapy, and immunotherapy, but only a few instances have shown a therapeutic response (10). Moreover, it is noted that brain metastasis can reappear within 5–7 months following surgical or after regression in response to systemic treatment (3, 19).
Local disease progression rather than distant metastasis is the most common cause of death (20). The overall survival of patients with brain metastases is noted to be worse than that of patients without brain metastases with a mean survival of 3 months (3, 18).