Diffuse pulmonary lymphatic disease presenting as interstitial lung disease in adulthood: report of 3 cases.

Oct 2012

Boland JM, Tazelaar HD, Colby TV, Leslie KO, Hartman TE, Yi ES.

Source

Departments of *Laboratory Medicine and Pathology ‡Radiology, Mayo Clinic, Rochester, MN †Mayo Clinic, Scottsdale, AZ.

Abstract

Diffuse pulmonary lymphatic diseases are typically diagnosed shortly after birth or in childhood, but rarely may become evident in adulthood. We report 3 adult patients who presented with diffuse interstitial lung disease clinically and radiologically but on biopsy were found to have diffuse pulmonary lymphatic disease (2 cases of pulmonarylymphangiectasis and 1 case of pulmonary lymphangiomatosis). 

These patients presented with the insidious onset of symptoms including shortness of breath and cough. Imaging studies of the chest showed diffuse pulmonary interstitial opacities, often with a perilymphatic distribution. The clinical differential diagnostic considerations before surgical lung biopsy included infection, neoplasm, and interstitial lung disease. The histopathologic features included abnormal vessels and associated fibrosis following lymphatic routes, namely visceral pleura, bronchovascular bundles, and interlobular septa. 

Lymphangiectasis was characterized by dilation of normally distributed lymphatic spaces, whereas lymphangiomatosis showed a complex anastamosing proliferation of lymphatic vascular spaces without significant dilatation. The dilated lymphatic spaces often had undergone muscularization, which could easily lead to misclassification as veins. Immunohistochemical staining for the lymphatic endothelial marker D2-40 was helpful in correctly classifying these lesions. 

Diffuse pulmonary lymphatic disease can rarely present in adulthood, wherein the histologic findings can be subtle and could be overlooked as nonspecific reactive changes or misdiagnosed as an idiopathic interstitial lung disease. Recognition of the characteristic lymphangitic distribution of abnormally dilated or reduplicated lymphatic spaces is key to the correct diagnosis.

American Journal of Surgical Pathology

Corneal angiogenesis and lymphangiogenesis.

Oct 2012

Regenfu B, Bock F, Cursiefen C.

Source

Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.

Abstract

PURPOSE OF REVIEW:

The purpose of the present review is to describe new antilymphangiogenic treatment strategies and recent findings on strain-dependency of corneal lymphangiogenesis and the interdependency between blood and lymphatic vessel growth.

RECENT FINDINGS:

Studies on mice have revealed that apart from haemangiogenesis, lymphangiogenesis can also differ markedly between several mouse strains under normal and inflammatory conditions. Although haemangiogenesis and lymphangiogenesis are closely interconnected in their spatial-temporal patterning, recent data suggest that they can also occur independently.

SUMMARY:

Understanding the coordinated regulation of blood and lymphatic vessel growth and genetic factors determining lymphangiogenesis in more detail could improve the development of specifically targeted antihaemangiogenic or antilymphangiogenic strategies.

Lippincott, Wilkins & Williams

Macrophage-Mediated Lymphangiogenesis: The Emerging Role of Macrophages as Lymphatic Endothelial Progenitors.

Sept 2012

Ran S, Montgomery KE.

Source

Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine, 801 N. Rutledge, Springfield, IL 62794, USA.

Abstract

It is widely accepted that macrophages and other inflammatory cells support tumor progression and metastasis. During early stages of neoplastic development, tumor-infiltrating macrophages (TAMs) mount an immune response against transformed cells. Frequently, however, cancer cells escape the immune surveillance, an event that is accompanied by macrophage transition from an anti-tumor to a pro-tumorigenic type. The latter is characterized by high expression of factors that activate endothelial cells, suppress immune response, degrade extracellular matrix, and promote tumor growth. Cumulatively, these products of TAMs promote tumor expansion and growth of both blood and lymphatic vessels that facilitate metastatic spread. Breast cancers and other epithelial malignancies induce the formation of new lymphatic vessels (i.e., lymphangiogenesis) that leads to lymphatic and subsequently, to distant metastasis. Both experimental and clinical studies have shown that TAMs significantly promote tumor lymphangiogenesis through paracrine and cell autonomous modes. The paracrine effect consists of the expression of a variety of pro-lymphangiogenic factors that activate the preexisting lymphatic vessels. The evidence for cell-autonomous contribution is based on the observed tumor mobilization of macrophage-derived lymphatic endothelial cell progenitors (M-LECP) that integrate into lymphatic vesselsprior to sprouting. This review will summarize the current knowledge of macrophage-dependent growth of new lymphatic vessels with specific emphasis on an emerging role of macrophages as lymphatic endothelial cell progenitors (M-LECP).

NIH Public Access