Usually, lesions are asymptomatic or do not show any evidence of a disease, but, mostly, patients may have random break outs of some bleeding and major drainage of clear fluid from ruptured vesicles.Cavernous lymphangioma first appears during infancy, when a rubbery nodule with no skin changes becomes obvious in the face, trunk, or extremity. These lesions often grow at a rapid pace, similar to that of raised hemangiomas. No family history of prior lymphangiomas is described.Cystic hygroma causes deep subcutaneous cystic swelling, usually in the axilla, base of the neck, or groin, and is typically noticed soon after birth. If the lesions are drained, they will rapidly fill back up with fluid. The lesions will grow and increase to a larger size if they are not completely removed in surgery. Diagnosis
Cases of lymphangioma are diagnosed by histopathologic inspection. In prenatal cases, lymphangioma is diagnosed during the late first trimester or early second trimester using an ultrasound. Other imaging methods such as CT and MRI scans are useful in treatment planning, delineate the size of the lesion, and determine its surrounding vital structures. T2-weight MRI is useful to differentiate lymphangioma from surrounding structures due to its high T2 signal. Classification
Lymphangiomas have traditionally been classified into three subtypes: capillary and cavernous lymphangiomas and cystic hygroma. This classification is based on their microscopic characteristics. A fourth subtype, the hemangiolymphangioma is also recognized. Capillary lymphangiomas
Capillary lymphangiomas are composed of small, capillary-sized lymphatic vessels and are characteristically located in the epidermis.
Why the embryonic lymph sacs remain disconnected from the rest of the lymphatic system is also not known.Cystic lymphangioma that emerges during the first two trimesters of pregnancy is associated with genetic disorders such as Noonan syndrome and trisomies 13, 18, and 21. Chromosomal aneuploidy such as Turner syndrome or Down syndrome were found in 40% of patients with cystic hygroma. Pathophysiology
In 1976, Whimster studied the pathogenesis of lymphangioma circumscriptum, finding lymphatic cisterns in the deep subcutaneous plane are separated from the normal network of lymph vessels. They communicate with the superficial lymph vesicles through vertical, dilated lymph channels. Whimster theorized the cisterns might come from a primitive lymph sac that failed to connect with the rest of the lymphatic system during embryonic development.A thick coat of muscle fibers that cause rhythmic contractions line the sequestered primitive sacs. Rhythmic contractions increase the intramural pressure, causing dilated channels to come from the walls of the cisterns toward the skin. He suggested that the vesicles seen in lymphangioma circumscriptum are outpouchings of these dilated projecting vessels. Lymphatic and radiographic studies support Whimsters observations. Such studies reveal that big cisterns extend deeply into the skin and beyond the clinical lesions. Lymphangiomas that are deep in the dermis show no evidence of communication with the regular lymphatics. The cause for the failure of lymph sacs to connect with the lymphatic system is not known.Microscopically, the vesicles in lymphangioma circumscriptum are greatly dilated lymph channels that cause the papillary dermis to expand. They may be associated with acanthosis and hyperkeratosis.