Brain Metastases from Primary Cardiac Tumors: A Systematic Review of Diagnosis, Treatment, and Prognosis

Abstract

Background: Primary cardiac tumors (PCTs) are rare entities, with only a minority being malignant and capable of distant dissemination. Among the rarest and most challenging metastatic events are brain metastases originating from cardiac tumors. Due to the heart's direct access to systemic circulation, even benign tumors such as atrial myxomas may cause cerebral embolic phenomena. Understanding the distinct biological behavior, diagnostic pathways, therapeutic strategies, and prognostic implications of these cases remains limited by the scarcity of the available literature. Methods: A systematic review was conducted following PRISMA guidelines. PubMed, Scopus, Embase, and other major databases were systematically searched using specific MeSH terms and keywords related to cardiac tumors and brain metastases. After applying strict inclusion and exclusion criteria, nineteen studies were included, comprising sixteen single-patient case reports and three multi-patient series. Extracted data included tumor histology, cardiac and brain imaging findings, neurological presentation, treatment approaches, and patient outcomes. Results: A total of 320 patients were analyzed. Atrial myxomas represented the predominant benign tumors causing embolic cerebral events, while angiosarcomas and other cardiac sarcomas were responsible for true hematogenous brain metastases. Brain involvement was frequently hemorrhagic and manifested with seizures, focal deficits, or signs of intracranial hypertension. Cardiac echocardiography and cardiac magnetic resonance imaging (CMR) were essential for tumor detection, while brain MRI, including SWI and DWI sequences, and CT scanning were critical for cerebral lesion characterization. Treatment strategies varied according to tumor type and included surgery, radiotherapy, and systemic therapies. Malignant cardiac tumors correlated with a poor prognosis, with median survival post-CNS involvement ranging from 12 to 14 months. Conclusions: Brain metastases from PCTs, though rare, represent a distinct and serious clinical phenomenon. Benign tumors like myxomas mainly cause embolic cerebral events, whereas malignant tumors, particularly sarcomas, lead to true metastatic brain lesions. Recognizing this biological distinction is crucial for diagnosis, prognostication, and therapeutic planning. An integrated multidisciplinary approach combining advanced cardiac and neuroimaging techniques is vital for early detection and appropriate management. Despite multimodal treatment, survival remains limited, underscoring the urgent need for novel targeted therapies and improved surveillance strategies.

Keywords: brain metastases; cardiac myxoma; cardiac sarcoma; cardiac tumors; multimodal imaging.

Figure 1

PRISMA 2020 flow diagram illustrating the study selection process. Out of 87 initially identified records, 34 duplicates were removed. After screening 53 unique studies, 19 were excluded based on title/abstract. Of the 34 full-text articles assessed for eligibility, 15 were excluded for incomplete or irrelevant data. Nineteen studies were included in the final analysis (sixteen case reports and three multi-patient series).

Figure 2

Timeline distribution of the included studies. Most publications on this rare topic have emerged in the last decade.

Figure 3

Age distribution of patients with cardiac tumors associated with brain involvement. Most patients are diagnosed between the ages of 40 and 50.

Figure 4

Histopathological distribution of cardiac tumors: Myxomas were the most frequent benign tumors, followed by angiosarcomas and undifferentiated sarcomas among malignant lesions.

Figure 5

Comparative histological breakdown of cardiac tumors across the three largest included studies (Brinjikji [13], Guan [15], Siontis [8]). Myxomas dominated Brinjikji’s cohort, while angiosarcomas and undifferentiated sarcomas were prevalent in the Guan and Siontis series.

Figure 6

Anatomical distribution of cardiac tumors: The left atrium is the most frequently involved site (78.44%), followed by the right atrium (20%) and pericardium (1.56%).

Figure 7

Distribution of patient survival time after diagnosis. The median follow-up duration was 16 months. The interquartile range (IQR) for survival was 11 to 39 months, meaning that 25% of patients had a survival of 11 months or less, while 75% survived up to 39 months.