Complications in the natural course — Lymphatic malformation

A typical complication of cystic lymphatic malformation (hereafter “LM”) in its natural course is superinfection, usually with bacteria. It leads to massive local inflammation, which is difficult to treat conservatively and not infrequently can result in systemic infection.

Another typical complication, especially when the LM involves the skin, is the repeated occurrence of erysipelas and lymphangitis. If they occur repeatedly, they can further worsen the already impaired lymphatic transport capacity in an extremity. Early therapy is absolutely necessary in this case.

Especially macrocystic LMs can acutely hemorrhage into the cysts, probably via communications with the venous system, which is embryologically closely related to and always communicates with the lymphatic system. Acute hemorrhage results in acute enlargement of the cyst with rapidly increasing space-occupying effects. The cyst then becomes acutely painful and indurated. Especially in the neck area, this can have dramatic consequences for the upper airways.

When parts of a lymphatic malformation are being resected, a wound drain is often inserted. Lymph leaks into the wound from opened lymphatic ducts, which can take varying lengths of time to resolve, sometimes up to several weeks. After removal of a wound drain, lymph may re-accumulate in the wound area with the formation of a lymph seroma. In this case, a second drain  usually has to be inserted, which can also be used for repeat sclerotherapy.

Postoperative wound infections of the surgical site are possible and require antibiotic therapy for up to three weeks.

Surgical resection but also sclerotherapy (mainly with pure alcohol) and interstitial laser treatment carry the risk of injury to important structures in the surrounding area. At risk structures are the various branches of the facial nerve, the accessory nerve, the cervical and brachial plexus, and, in intrathoracic surgery, the phrenic nerve.

During neck or intrathoracic surgery, the thoracic duct or one of its collateral branches may be injured. This can result in dangerous loss of chyle to the outside via overlying drains or chylothorax or chylous ascites. This complication can be very difficult to treat. An attempt can be made to find and close the leak surgically, to close the thoracic duct via thoracoscopy, or to seal the leak site minimally invasively via lymphangiography and radiological interventional puncture of the cisterna chyli.

Even pretreated residual portions of a lymphatic malformation can swell in the setting of viral infections or rarer hematogenous bacterial infections and, in the worst case, can cause respiratory compromise.