Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 39-04: Pulmonary Metastasis + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Identification of a primary cancer Radiographic findings consistent with pulmonary spread from the cancer (eg, nodules) Exclusion of other diseases in the differential diagnosis of multiple pulmonary nodules +++ General Considerations ++ Represent metastases from extrapulmonary malignancies Almost any cancer can spread to the lung, usually hematogenously via the pulmonary artery Lung metastases are found in 20–55% of patients with various metastatic malignancies + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ Symptoms are uncommon, but include cough, hemoptysis, and dyspnea in advanced cases Symptoms are most commonly referable to the primary tumor +++ Differential Diagnosis ++ Bronchogenic carcinoma Lymphoproliferative cancer Tuberculosis Lung abscess Granulomas (eg, tuberculous, fungal) Coccidioidomycosis Histoplasmosis Sarcoidosis Silicosis Coal worker's pneumoconiosis Mycobacterium avium complex Arteriovenous malformations Rheumatoid nodules Hamartomas Granulomatosis with polyangiitis Methotrexate-induced + Diagnosis Download Section PDF Listen +++ +++ Laboratory Tests ++ Appropriate studies should be ordered in a search for the primary tumor Occasionally, cytologic studies of pleural fluid or pleural biopsy are diagnostic +++ Imaging Studies ++ Chest radiograph usually shows multiple spherical densities with sharp margins Lesions are usually bilateral, pleural, or subpleural and are more common in lower lung zones CT imaging of the chest, abdomen, and pelvis may reveal the site of a primary tumor and will help determine feasibility of surgical resection of the metastatic lung tumors PET-CT FDG scan is helpful in identifying the site of a primary cancer or identifying other areas of extrathoracic metastasis Mammography should be performed in a search for the primary tumor +++ Diagnostic Procedures ++ If a primary tumor cannot be found, tissue from lung lesions may be obtained by bronchoscopy, percutaneous biopsy, or thoracotomy + Treatment Download Section PDF Listen +++ +++ Surgery ++ Resection of a solitary pulmonary nodule is often prudent in a patient with known current or prior extrapulmonary cancer Local resection of one or more pulmonary metastases is feasible in a few carefully selected patients with various sarcomas and carcinomas (such as testis, colorectal, and kidney) Only about 15–25% of patients with metastatic solid tumor have metastases limited to the lungs and are therefore surgical candidates Surgical resection should be considered only if The primary tumor is under control The patient has adequate cardiopulmonary reserve to tolerate resection All metastatic tumor can be resected Effective nonsurgical approaches are not available There is no evidence of extrathoracic metastases that are not controlled Patients who are not surgical candidates but have solitary or limited metastatic disease to the lungs may be candidates for stereotactic radiosurgery, radioablation or cryotherapy Repeat surgery for pulmonary metastases can be performed as long as the criteria for pulmonary metastatectomy are still met +++ Therapeutic Procedures ++ Management consists of treatment of the primary malignancy and any pulmonary complications + Outcome Download Section PDF Listen +++ +++ Prognosis ++ Overall 5-year survival rate of 36% and 10-year survival rate of 26% after complete resection of pulmonary metastases +++ When to Refer ++ All patients deserve an evaluation by a multidisciplinary lung cancer evaluation and treatment program For bronchoscopy or thoracotomy All patients with advanced disease should be referred to a palliative care specialist +++ When to Admit ++ Respiratory distress, altered mental status, pain control + References Download Section PDF Listen +++ + +Handy JR et al. Expert consensus document on pulmonary metastasectomy. Ann Thorac Surg. 2019 Feb;107(2):631–49. [PubMed: 30476477] + +Petrella F et al. Pulmonary metastatectomy: an overview. J Thorac Dis. 2017 Oct;9(Suppl 12):S1291–8. [PubMed: 29119017]