Tumor Embolism
Epidemiology
- Most cases are associated with breast cancer, gastric cancer, or lung cancer
Etiology
- Mucin-Producing Adenocarcinomas (occur mainly in cases with liver mets/ usually microscopic tumor emboli):
- Breast Cancer: accounts for 67% of tumor emboli cases (Schriner, 1991)
- Gastric Cancer (first case reported in 1897):
- Colon Cancer:
- Renal Cell Carcinoma (usually macroscopic -> emboli via IVC):
- Hepatoma (usually macroscopic -> emboli via IVC): older literature suggests a high incidence with hepatoma
- Choriocarcinoma (usually macroscopic -> emboli via IVC): trophoblastic tumor fragments may embolize during hysterectomy or during resection
- Sarcoma (usually macroscopic -> emboli via IVC):
- Atrial Myxoma:
- Head Trauma: brain cells may be found in lung vasculature in some cases
- Abdominal Trauma: liver cells may be found in lung vasculature in some cases
- CPR: bone marrow may be found in lung vasculature in some cases
- Lung Cancer:
- Prostate Cancer:
Physiology
- Occlusion of the microvasculature by metastatic tumor emboli
Diagnosis
- ABG: hypoxemia
- CXR/Chest CT Patterns
- Lymphangitic pattern: seen in some cases (lymphangitic mets may be seen histologically, more than is evident on CXR)
- Normal CXR: present in most cases
- CT Angio: usually does not show thrombi
- V/Q Scan: usually abnormal with multiple peripheral subsegmental perfusion defects
- Pulm angio: usually normal (some cases have defects)
- Swan: PA blood samplng in PCWP position may demonstrate tumor cells
Clinical Syndromes
- Acute Lung Injury-ARDS (see [[Acute Lung Injury-ARDS]])
- Due to massive microscopic emboli
- Acute dyspnea:
- Pulmonary Hypertension/Cor Pulmonale (see Pulmonary Hypertension, [[Pulmonary Hypertension]])
- Classic pattern reported in tumor emboli
- Dyspnea (common):
- Cough (8-47% of cases):
- Pleuritic chest pain (18-28% of cases):
- Hemoptysis (5-18% of cases):
- Signs of pulmonary HTN (only 15-20% of cases):
Treatment
- Surgery: has been reported to be useful in cases with large tumor emboli from RCC or atrial myxoma
- Chemo: useful for microscopic cases from breast cancer or choriocarcinoma
References
- Pulmonary tumor embolism: a review of the literature. Am J Med 2003;115:228 –32.
- [Pulmonary arterial hypertension due to tumor emboli]. Rev Mal Respir 2007;24:359–66.