Pr08 lymphatic malformations and the molecular basis of lymphangiogenesis. Options
Pr08 lymphatic malformations and the molecular basis of lymphangiogenesis.ANZ J Surg. 2007 May
Ch'ng S, Tan ST. Wellington Regional Plastic Unit, Hutt Hospital, Wellington, New Zealand.
This paper reviews the clinical features of lymphatic malformations and the molecular basis of embryonic lymphangiogenesis.
Lymphatic malformations are classified as microcystic, macrocystic, or combined. Most commonly found in the axilla/chest and cervicofacial region, they can be localised or diffuse. The commonest complications are intralesional bleeding and infection. Other significant complications are due mainly to their mass effect on nearby anatomic structures including the airway and eyeball, and soft tissue and skeletal overgrowth including macrocheilia, macroglossia, macrotia, macromala and mandibular prognathism, resulting in functional problems in feeding, speech, occlusion, oral hygiene, and disfigurement.
The characteristic radiological finding of a LM on gadolinium-enhanced T1-weighted MRI is a low-density lesion with septation or rim enhancement. Histologically, LMs are cystic lesions that contain eosinophilic proteinaceous fluid whose walls are composed of smooth and skeletal muscle fibres, collagen and lymphocytes. Management options range from observation, comfort cares, empirical antibiotic treatment for LM cellulitis to sclerotherapy, surgical excision and Nd:YAG laser for selected cases.
Lymphangiogenesis is believed to occur in four sequential but overlapping stages: lymphatic endothelial cell competence, bias and specification, and finally lymphatic vessel terminal differentiation and maturation. Multiple genes are involved in this process including Lyve1, Nrp2, podoplanin, Prox1, VEGFR3, VEGFC and Ang2. Developmental defects during embryonic lymphangiogenesis result in lymphatic malformations.
PMID: 17490238 [PubMed - in process]