Primary Nodal Lymphangioma: A Rare Case Report and Literature Review

Abstract Introduction/Objective Lymphangiomas are benign nodal vascular tumors commonly seen in the skin, mucosa, and soft tissue; however, its occurrence in lymph nodes is extremely rare, with only a few cases reported in English literature. Methods We report a case of a 20-year-old female who presented with a 6 cm right upper thigh mass below the inguinal region that has been gradually increasing in size over the past three months. Ultrasound showed a cystic appearance. An excisional biopsy was performed to yield a thin-walled cystic mass filled with clear fluid. The mass appeared to be connected to a regional lymph node. Histologic examination revealed a multiloculated thin-wall cyst involving the hilum of the lymph node. The cyst is lined by flat lymphatic endothelial cells with focally disorganized smooth muscle at the wall of large channels and peripheral lymphoid aggregates. The rest of the lymph node shows reactive change with vascular proliferation and congestion. Results Lymphangiomas are soft, relatively well-circumscribed hamartomatous malformations due to the failure of the lymphatic system to communicate with the venous system. This leads to abnormal rests of lymphatic tissue that proliferate and accumulate fluid, causing their cystic morphology. Lymphangiomas are classified as capillary, cavernous, and cystic forms. Imaging techniques such as ultrasonography, mammography, and magnetic resonance imaging may aid in clinical diagnosis and follow-up. Histologically, cavernous lymphangiomas show numerous narrow cavernous spaces lined by a single layer of attenuated endothelial cells, and containing amorphous eosinophilic fluid with few lymphocytes. These spaces may contain blood resulting in misdiagnosis of this lesion as cavernous hemangioma; however, increased lymphoid cells in the stroma, more irregular cavernous spaces, support the diagnosis of lymphangioma. Conclusion Lymphangiomas are slowly progressive painless lesions that frequently recur in cases of incomplete excision. It is important to identify this primary nodal lymphangioma to avoid misdiagnosis of benign vascular proliferation, benign vascular tumor, or malignant vascular tumor.