Objective: Define the clinical presentation, diagnostic value of preoperative imaging, surgical management, and outcomes of treatment of congenital cervical thymic remnants in children.
Design: Retrospective cohort.
Setting: Single tertiary care institution.
Patients: 20 children who underwent excision of cervical thymic remnant, 1975-2006.
Main outcomes measured: Utility of preoperative imaging to diagnose cervical thymic anomalies; success of surgical treatment of cervical thymic remnants.
Results: A total of 20 children were identified, with an average age of 6.98+/-5.63 years. All ectopic thymus tissue was found in the embryonic distribution area associated with the third branchial pouch. Fourteen patients underwent excision of a cystic ectopic thymus. Four of these patients exhibited lesions isolated to the cervical region, and 10 patients displayed lesions involving cervicomediastinal areas. Six patients underwent excision of solid ectopic cervical thymus, and each of these was an unanticipated mass encountered during surgical dissection for other procedures. 83% of patients with solid ectopic cervical thymus presented at age 3 or younger. Physical exam and preoperative imaging correctly diagnosed thymic remnants in 15% patients. Resection of thymic remnants was successful in all patients, and there were no recurrences.
Conclusions: Though rare, thymic remnants should be considered in the differential diagnosis of masses presenting in locations associated with derivatives of the third branchial pouch. Though preoperative imaging is helpful in identifying the extent of these lesions, congenital thymic remnants prove difficult to diagnosis radiologically. Surgical excision is the diagnostic and therapeutic treatment of choice in the management of cervical thymic remnants.