Cardiac tumors are rare neoplasms of the heart and pericardium, classified into primary cardiac tumors (extremely rare, originating from cardiac tissue) and secondary metastatic cardiac tumors (20-40 times more prevalent, from distant primary cancers). Primary tumors are further divided into benign (~75% of primary tumors) and malignant (~25% of primary tumors).

• Etiology and Classification:
  • Benign Primary Tumors: The most common is myxoma (~50% of all primary tumors, 75% located in the left atrium), followed by lipoma, papillary fibroelastoma, rhabdomyoma (most common in children), fibroma, and hemangioma. Complete surgical resection is curative.
  • Malignant Primary Tumors: The vast majority are sarcomas (angiosarcoma, undifferentiated pleomorphic sarcoma, leiomyosarcoma), with rare primary cardiac lymphoma. These are highly aggressive, with a poor prognosis.
  • Secondary Metastatic Tumors: Most commonly originate from lung, breast, esophageal, hematological, melanoma, and gastrointestinal cancers.
• Epidemiology: Primary cardiac tumors have an annual incidence of ~0.0017-0.028% in the general population, with an autopsy prevalence of ~0.02-0.05%. China has the world's largest cardiac tumor patient population, with an estimated 10,000-15,000 new primary cases diagnosed annually.
• Clinical Manifestations: Symptoms are highly variable and non-specific, often mimicking common cardiovascular diseases. The three primary clinical syndromes are:
  • Obstructive symptoms: Exertional dyspnea, syncope, chest pain, heart failure, or sudden death from intracavitary tumor blood flow obstruction.
  • Systemic/embolic symptoms: Constitutional symptoms (fever, weight loss, fatigue), elevated inflammatory markers, and thromboembolic events (~30-40% of myxoma patients).
  • Arrhythmic/pericardial symptoms: Atrial/ventricular arrhythmias, heart block, pericardial effusion, or cardiac tamponade.
• Diagnosis: TTE is the first-line screening modality, identifying tumor location, size, mobility, and hemodynamic impact. TEE provides superior visualization of small tumors and attachment sites. Cardiac MRI is the gold standard for tissue characterization. Endomyocardial biopsy provides histopathological confirmation.

• Benign Primary Tumors: Complete surgical resection is the gold standard and curative treatment, indicated for all symptomatic tumors and asymptomatic tumors with high embolic/obstructive risk. Resection is performed via sternotomy or minimally invasive thoracoscopic/robotic approaches, with a near 100% cure rate and <5% recurrence rate for myxoma.
• Malignant Primary Tumors: Requires a multidisciplinary comprehensive approach, including surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy. Complete surgical resection is attempted for localized non-metastatic disease. For unresectable/metastatic disease, palliative systemic therapy is used to relieve symptoms and prolong survival. The prognosis remains poor, with a median overall survival of 6-12 months for advanced disease.
• Secondary Metastatic Tumors: Treatment is palliative, focused on managing the primary malignancy and relieving cardiac symptoms. Systemic therapy for the primary cancer is the mainstay, with local interventions including pericardiocentesis/window for malignant effusion/tamponade, surgical resection for isolated symptomatic metastases, and radiotherapy for local symptom control.
• Supportive Care: Guideline-directed management of heart failure, arrhythmias, thromboembolism, and pericardial complications.