Thymic cavernous lymphangioma in an adult: a case report

Lymphangiomas are benign tumors frequently seen in children due to congenital causes with less than 150 cases have been reported in the adult population as of 2022. About 1% of all lymphangiomas occur in the mediastinum; moreover, 3-subtypes exist and cystic lymphangiomas being the most common; meanwhile, simplex and cavernous are rarer forms. A 34-year-old North African woman, nonsmoker, with no significant medical history presented to our hospital with complaints of a painful cervical swelling and exertional dyspnea. The swelling was initially small in size but had evolved over the past 2 months. On examination, an anterior cervical swelling could be observed. Palpation revealed an approximately 4 × 2 cm tender, non-indurated mass, adherent to the deep plane, non-plunging during swallowing, not associated with any signs of local inflammation or collateral circulation, limiting neck movement whose inferior plane could not be detected. Computed tomography (CT) scan showed a 4.6*1.7*6 cm well-circumscribed mass located in the anterior mediastinum. Scanno-guided biopsy and biological test results for: beta-HCG, TSH, LDH, alpha-fetoprotein and anti-RACH were all negative. En bloc resection via sternotomy for removal of the mass was performed without complication. Intraoperative surgery revealed a well-encapsulated mass noninvasive of major blood vessels within the thymic cavity. Postoperative histopathology results were suggestive of a cavernous lymphangioma. No recurrence occurred. Lymphangiomas are rare adult tumors that infrequently occur in the mediastinum. We report an adult case of an even rarer form of the tumor located within the thymic cavity something that, to the best of our knowledge, has never been described. Therefore, Cavernous lymphangioma should be considered in the clinical assessment of adult patients presenting with an anterior mediastinal mass.