Case Report: Misdiagnosed cystic lymphangioma presenting as recurrent submandibular cellulitis: diagnostic and therapeutic pitfalls

<ns3:p>Introduction Cystic lymphangioma is a rare benign lymphatic malformation that typically presents in childhood. Adult-onset cases are exceptionally rare and often misdiagnosed due to their rarity and overlapping features with more common pathologies. Observation We report the case of a 55-year-old man with recurrent submandibular swelling and cellulitis, initially misdiagnosed and managed as an infectious or congenital pathology. Persistent recurrences, despite medical and surgical interventions, prompted further imaging, which revealed a multiloculated cystic lesion suggestive of a lymphatic malformation. Complete surgical excision confirmed the diagnosis of cystic lymphangioma. The postoperative course was uneventful, and no recurrence was observed at the one-year follow-up. Conclusion Adult cystic lymphangioma of the submandibular region can mimic more common conditions such as branchial cysts or sialadenitis, delaying accurate diagnosis and appropriate treatment. MRI is pivotal for diagnosis, and surgery remains the mainstay in recurrent or complex forms. A multidisciplinary evaluation is essential to ensure optimal management.</ns3:p>