MD Nexus

Lung Metastases-Endobronchial

Etiology

Breast Cancer (see Breast Cancer)

  • Epidemiology
    • Breast Cancer is the Most Common Tumor to Metastasize to the Airway
      • Breast Cancer Accounts for 36% of Endobronchial Metastases (By Autopsy Studies)
    • Endobronchial Metastases Occur More Commonly in Postmenopausal Breast Cancer Cases
    • Endobronchial Metastases from Breast Cancer May Occur Up to 33 Years After the Initial Breast Cancer Diagnosis
    • Rarely, Breast Cancer May Also Contiguously/Directly Invade the Trachea from Mediastinal Mets

Cervical Cancer (see Cervical Cancer)

  • Epidemiology
    • Cervical Cancer is a Common Etiology of Endobronchial Metastases

Chronic Lymphocytic Leukemia (CLL) (see Chronic Lymphocytic Leukemia)

  • Epidemiology
    • Chronic Lymphocytic Leukemia-Associated Endobronchial Metastases May Occur Late in Course
    • Chronic Lymphocytic Leukemia May Rarely Infiltrate the Bronchial Mucosa

Colorectal Cancer (see Colorectal Cancer)

  • Epidemiology
    • Colorectal Cancer is a Common Etiology of Endobronchial Metastases

Endometrioma (see Endometrioma)

  • Epidemiology
    • Endometrioma May Metastasize to the Airways in Some Cases

Esophageal Cancer (see Esophageal Cancer)

  • Epidemiology
    • Esophageal Cancer May Directly Invade the Trachea
  • Clinical
    • When Tracheal Invasion Occurs, it Usually at the Level of the Left Mainstem Bronchus

Germ Cell Tumor (see Germ Cell Tumor)

  • Epidemiology
    • Germ Cell Tumors May Metastasize to the Airways in Some Case

Head and Neck Cancer (see Head and Neck Cancer)

  • Epidemiology
    • Head and Neck Cancer May Metastasize to the Airways in Some Cases

Hepatocellular Carcinoma (see Hepatocellular Carcinoma)

  • Epidemiology
    • Cases Have Been Reported (Dig Liver Dis, 2021) [MEDLINE]

Hodgkin Lymphoma (see Hodgkin Lymphoma)

  • Epidemiology
    • Hodgkin Lymphoma May Involve the Airway by Direct Extension from Hilar/Peribronchial Lymph Nodes or May Seed the Airway Via Hematogenous or Lymphatic Spread

Kaposi Sarcoma (see Kaposi Sarcoma)

  • Epidemiology
    • Kaposi Sarcoma is Associated with Human Immunodeficiency Virus (HIV) Infection
    • Kaposi Sarcoma Involves the Lungs in 33-50% of Cases

Lymphoma (see Lymphoma)

  • Epidemiology
    • Lymphoma May Involve the Airway by Direct Extension from Hilar/Peribronchial Lymph Nodes or May Seed the Airway Via Hematogenous or Lymphatic Spread

Melanoma (see Melanoma)

  • Epidemiology
    • Melanoma is a Common Etiology of Endobronchial Metastases

Ovarian Cancer (see Ovarian Cancer)

  • Epidemiology
    • Ovarian Cancer May Metastasize to the Airways in Some Cases

Plasmacytoma (see Multiple Myeloma)

  • Epidemiology
    • Plasmacytoma May Metastasize to the Airways in Some Cases

Renal Cell Cancer (see Renal Cancer)

  • Epidemiology
    • Renal Cell Cancer is a Common Etiology of Endobronchial Metastases

Sarcoma

  • Epidemiology
    • Sarcoma May Metastasize to the Airways in Some Cases

Testicular Cancer (see Testicular Cancer)

  • Epidemiology
    • Testicular Cancer is an Uncommon Etiology of Endobronchial Metastases

Thymic Carcinoma (see Thymoma)

  • Epidemiology
    • Thymic Carcinoma May Metastasize to the Airways in Some Cases

Thyroid Cancer (see Thyroid Cancer)

  • Epidemiology
    • Thyroid Cancer May Directly Invade Lower Larynx/Trachea or May Metastasize to the Trachea

Urothelial Cell Carcinoma (Transitional Cell Carcinoma) (see Urothelial Cell Carcinoma)

Physiology

Malignancies May Hematogenously Metastasize to the Airways

  • However, This Rarely Occurs in Absence of Parenchymal Lung Metastases

Diagnosis

Chest X-Ray (CXR) (see Chest X-Ray)

  • Inspiratory Chest X-Ray: may demonstrate underinflation
  • Expiratory Chest X-Ray: may demonstrate air trapping in affected lung

Ventilation/Perfusion (V/Q) Scan (see Ventilation/Perfusion Scan)

  • Ventilation/Perfusion May Reveal Decreased/Absent Ventilation and Decreased Perfusion to the Affected Side

Bronchoscopy (see Bronchoscopy)

  • Bronchoscopy is the Diagnostic Procedure of Choice to Demonstrate the Presence of Endobronchial Tumor
    • Endobronchial Biopsy (EBB)
      • While Endobronchial Biopsy May Be Useful, it is Generally Hazardous in the Setting of Highly Vascular Tumors (Such as Kaposi Sarcoma, etc) Due to the Risk of Hemorrhage

Chest Computed Tomography (Chest CT) (see Chest Computed Tomography)

  • Chest CT May Reveal Atelectasis (Associated with Airway Obstruction) or Post-Obstructive Pneumonia
    • In infants, Pores of Kohn are Poorly Developed (Hence, Obstruction is More Likely to Produce Distal Atelectasis)
    • Presence of Air Bronchogram: Suggests Only Partial Obstruction
    • Inspiratory (Lung Will Expand Normally) vs Expiratory (Lung Will Not Deflate Normally) Films May Reveal Partial Airway Obstruction
    • Also, the Mediastinum Will Shift Away from Affected Side on Expiration

High-Resolution Chest Computed Tomography (HRCT) (see Chest Computed Tomography)

  • High-Resolution Chest CT May Demonstrate Endobronchial Lesions in Some Cases

Clinical Manifestations

Pulmonary Manifestations

Hemoptysis (see Hemoptysis)

  • Epidemiology
    • Hemoptysis is Rare in Kaposi Sarcoma

Inspiratory “Bagpipe” Sign

  • Clinical
    • Prolonged Inspiratory Time on the Affected Side

Localize Expiratory Wheeze (see Wheezing)

  • Clinical
    • Localize Expiratory Wheeze May Over the Site of Airway Obstruction

Symptoms/Signs of Airway Obstruction

  • Epidemiology
    • Symptoms/Signs of Airway Obstruction are Rare in Kaposi Sarcoma (see Kaposi Sarcoma)

Treatment

Management of Thyroid Cancer (with Direct Airway Invasion)

  • May Be Resected with Tracheal Reconstruction

Management of Other Airway Tumors

  • Airway Laser/Airway Stenting May Be Required

References

Etiology