Refers to the diffuse infiltration and obstruction of pulmonary parenchymal lymphatic channels by tumor.
Various neoplasms can cause lymphangitic carcinomatosis (LC), but 80% are adenocarcinomas. The most common primary sites are the breasts, lungs, colon, and stomach.
The usual presenting complaint is breathlessness. Occasionally, patients have a dry cough or hemoptysis. Symptoms often precede the development of any radiographic abnormality.
Although chest radiographs appear normal for 30 % – 50 % of patients with histologically proven disease, pulmonary lymphangitic carcinomatosis has several characteristic changes that can be observed on radiographs:
- Bronchovascular markings with irregular outline
- Reticulonodular pattern with intraparenchymal extension of tumor
- Bilateral changes predominantly in the lower lobes of the lungs
- Kerley A and B lines
- Hilar and mediastinal lymphadenopathy
- Pleural effusion
In the appropriate clinical circumstances or when the chest radiographic findings are equivocal, the next investigation employs high-resolution computed tomography (HRCT) scanning. Although the appearance of LC on HRCT scans is nonspecific, the observation of certain features in a symptomatic patient with an appropriate history of malignancy is highly suggestive of LC; in such instances, further investigation is generally not required.
Less than half of patients with pulmonary lymphangitic carcinomatosis who present with respiratory symptoms survive for 3 months. Corticosteroids may be effective in the management of dyspnea associated with carcinomatous lymphangitis.
Reference: Anish T, Lenox R. Pulmonary lymphangitic carcinomatosis as a primary manifestation of colon cancer in a young adult. Canadian Medical Association 2008; 179(4):338-340. Khan A. Lymphangitic carcinomatosis imaging. Emedicine (Updated: Aug, 2010). Internet. Accessed January 23, 2011. Available at http://emedicine.medscape.com/article/359006-overview.