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Published on: November 10, 2014
Challenges in diagnosing ectopic thymus tissue in children
Laura Claes1, Amélie Dendooven2, Jaques van Heerden1,3
1Paediatrics, Antwerp University Hospital, University of Antwerp, Edegem, Belgium.
Insights
A rare case of a fast-growing neck mass in a child was diagnosed as a hemorrhagic ectopic cervical thymic cyst. This finding highlights the importance of considering unusual diagnoses for pediatric neck masses.
Area of Science:
- Pediatric Surgery
- Head and Neck Pathology
- Developmental Biology
Background:
- Fast-growing cervical masses in children require urgent evaluation due to potential mass effects and a broad differential diagnosis.
- Ectopic cervical thymic cysts are rare congenital anomalies that can present as neck masses.
Observation:
- A 4.5-year-old boy presented with a rapidly enlarging, unilateral neck mass with concerning malignant features.
- Surgical excision and pathological examination were performed for diagnosis.
Findings:
- The mass was pathocytologically identified as a hemorrhagic ectopic cervical thymic cyst.
- Thymic cysts are uncommon causes of unilateral neck masses, typically slow-growing and asymptomatic.
Implications:
- This case underscores the necessity of including rare entities like hemorrhagic thymic cysts in the differential diagnosis of pediatric cervical masses.
- Surgical excision is the recommended treatment for symptomatic thymic cysts, with cautious consideration for preserving thymic tissue in pediatric patients.
Abstract:
The presentation of a fast-growing cervical mass necessitates prompt attention due to risk of the mass effect on vital structures and requires preferential screening for infections, bleeding and malignancies in an extensive list of differential diagnoses. This case report describes a 4.5-year-old boy with a fast-growing, unilateral lesion in the neck, with clinical features in keeping with malignant characteristics. Surgical excision with pathocytological examination revealed an exceptional diagnosis of haemorrhage in an ectopic cervical thymic cyst. Thymic cysts are a rare cause of unilateral masses in the neck, usually presenting as an asymptomatic, painless, slow-growing or stable mass anywhere along the thymopharyngeal duct. Spontaneous haemorrhages in thymic tissue can occur, often due to coagulation defects. Treatment of symptomatic thymic cysts is based on surgical excision. Partial resection of the thymus should be encouraged if possible, since clinical consequences of removing all thymic tissue in children are still unclear.
