Lymphangitic Carcinomatosis

Key Facts
  • Permeation of lymphatics by neoplastic cells
  • Tumor emboli or direct spread to lungs from hilar nodes or lung cancer mass
  • Seen with carcinoma of the lung, breast, pancreas, stomach, colon, prostate and other tumors
  • Unilateral disease - most commonly due to lung cancer
  • Radiography - may resemble interstitial edema; progressive disease
  • HRCT: nodular thickening of interlobular septa and bronchovascular bundles
  • Lung architecture preserved
  • Prognosis - poor
Imaging Findings

Chest radiography

  • Reticulonodular opacities, coarse bronchvascular markings, septal lines, subpleural edema at fissures
  • May resemble interstitial edema
  • Hilar and mediastinal lymphadenopathy may be present
  • Pleural effusion, common
  • Unilateral disease - most commonly due to lung cancer
  • Bilateral symmetric disease commonly due to extrathoracic primary tumor
  • Chest radiograph may be normal


CT/HRCT

  • HRCT best imaging to suggest diagnosis
  • Nodular thickening of interlobular septa and bronchovascular bundles
  • Septal lines and polygons with nodular or beaded appearance
  • Lung architecture preserved
  • Patchy ground glass and airspace opacities
  • Small centrilobular nodules, thickened centrilobular bronchovascular bundles
  • Peripheral or central distribution, basal predominance
  • Commonly asymmetric, may spare lobes or lungs
  • Smooth or nodular thickening of interlobar fissures
  • Pleural effusion
  • Hilar/mediastinal lymphadenopathy
Differential Diagnosis
  • Pulmonary edema
  • Interstitial pneumonia
  • UIP
  • Scleroderma
  • Drug reaction
  • Sarcoid
  • Asbestosis
  • Hypersensitivity pneumonitis
  • Differentiation
    • Lymphangitic carcinomatosis will not show architectural distortion or honeycombing. Progressive disease. Usually not occult but develops in patients with known malignancy
    • Progression of disease without treatment
Pathological Features
  • Frequent form of tumor spread
  • Permeation of lymphatics by neoplastic cells
  • Interstitial thickening of interlobular septa due to tumor cells, desmoplastic response, and dilated lymphatics
  • Hilar and mediastinal lymph nodes may or may not be involved
  • Pathogenesis
    • Hematogenous metastases i.e., tumor emboli to small pulmonary artery branches with subsequent spread along lymphatics
    • Some tumors such as lymphoma spread from hilar nodes retrograde into pulmonary lymphatics
    • Lung cancer can spread to adjacent lung along lymphatics
Clinical Presentation
  • Any age, male or female
  • Seen with carcinoma of the lung, breast, pancreas, stomach, colon, prostate and other tumors
  • Dyspnea, cough, progressive symptoms
  • Diagnosis evident in patients with known malignancy
  • If no known malignancy – sputum cytology, transbronchial biopsy, fine needle aspiration biopsy or open lung biopsy for diagnosis
  • Poor prognosis, 15% survive 6 months
References

Trapnell DH. Radiological appearance of lymphangitis carcinomatosa of the lung Thorax 19:251-260, 1964
Ren H, Hruban RH, Kuhlman JE, et al. Computed tomography of inflation-fixed lungs: the beaded septum sign of pulmonary metastases J Comput Assist Tomogr 13:411-416, 1989