A Right Wrist Lump FREE

A 42-year-old male gardener presents with a 5-cm wrist mass causing functional limitation and swelling of the right hand. The mass has been present since the patient was 12 years old and has progressively enlarged. History is negative for any disease or trauma. At age 26 years the patient underwent orthopedic surgical exploration, but no specific diagnosis was confirmed. The mass is pale, nontender, cold, nonpulsatile, and soft to palpation. The remainder of a general physical examination is unremarkable. Magnetic resonance imaging was not explanatory. Color duplex ultrasonography of the mass shows a cystic appearance with no arterialized flow surrounding the cephalic vein. Angiography reveals persisting contrast enhancement with delayed x-ray fluoroscopy acquisition time at the right wrist level (Figure 1).

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Lymphatic vessel malformation

D. Request vascular surgery consultation for radical excision

The key clinical feature in this case is a growing painless wrist mass in a young man. Congenital lymphatic vessel malformations are uncommon but may manifest in the extremities after birth and in adulthood. The soft, cystic appearance with no arterialized flow on ultrasonography and the delayed persistence of injected contrast on fluoroscopy are the main findings suggesting a vascular malformation of lymphatic vessels (Figure 2). Localized lymphatic malformations causing inability to perform daily tasks necessitates complete surgical excision, which is the preferred course of action in this case.

Vascular malformations are a complex pathological group of dysplastic vascular channels without any endothelial proliferation or spontaneous regression that may present as low-flow and high-flow lesions. Lymphatic vessel malformations (previously known as “cystic hygromas” or “lymphangiomas”) are classified as vascular malformations at low flow that can be found as focal or diffuse in deep or subcutaneous tissues of the neck, thorax, or extremities.^1- 2 Lymphatic malformations are typically composed of numerous thin-walled dilated lymphatic vessels that can be empty or contain eosinophilic material. The lining of these vascular channels shows relatively widely spaced endothelial nuclei. The shape of the channel tends to be irregular and the channels usually do not have a muscular layer surrounding the endothelial lining.

Most lymphatic malformations are congenital and the pathogenesis is unclear. Large lymphatic vessels might transmit pressure from underlying abnormal cisterns in an abnormal closed system. Furthermore, it is not clear why a congenitally determined process manifests in adulthood in some patients, as in this case. The differential diagnosis of patients presenting with a wrist lump includes ganglion cyst, inclusion cyst, tendon sheath infection/tumor, arthritis, tendinitis, and vascular malformations. Diagnostic imaging should be targeted at information required for treatment planning. Duplex ultrasonography would document fluid appearance and degree of vascularization. Magnetic resonance imaging would define the anatomical extent and involvement of the neighboring tissue layers.

Treatment depends on site, extension, and accessibility. Minimally invasive modalities (such as electrocautery, cryosurgery, or carbon dioxide laser) can be useful for the treatment of superficial, cutaneous diseases. Complete surgical excision is preferred for deeper localizations to decrease the rate of recurrence.³ Partial excision may be an acceptable alternative if surgical resection requires removal of vital structures.

Selective digital angiography would distinguish predominant vascular channels and identify hemodynamic properties and surrounding feeding vessels and should be performed when surgical excision is planned. In this case, given the progressive growth of the wrist mass associated with swelling and functional impairment of the right hand, surgical excision was a reasonable course in this patient.

Selective phlebography of the patient's right arm showed a multiple-channel low-flow lesion with persisting contrast enhancement at ultradelayed phases. This finding was suggestive of a vascular malformation related to the lymphatic network surrounding the distal cephalic vein. A macroscopic specimen was consistent with a fluid-filled vesicle lesion that bulged on the subcutaneous surface and strictly adhered to the cephalic vein. Diagnosis was confirmed by histopathologic examination revealing large dilated lymphatic channels of irregular shape with no endothelial proliferation. At 2 years after surgical excision, there were no recurrences of hand symptoms or wrist mass.