Patho-Anatomic Spectrum of Branchial Cleft Anomalies: Proposal of Novel Classification System.

Purpose: Histogenesis, nomenclature, and classification of branchial cleft anomalies (BCAs) have been subjects of controversy for decades. The purpose of this study was to investigate the accuracy of current developmental theories (congenital, lymph node, and hybrid branchial inclusion theories) in defining the anatomic and histopathological characteristics of BCAs.

Methods: Ninety consecutive patients with BCAs who underwent surgical excision were enrolled in this 2-center retrospective cohort study.

Results: The present study included 90 patients: 46 (51.11%) women and 44 (48.89%) men (P > .05). The mean age at presentation was 31.89±17.31 years. Altogether, 92 BCAs were identified within the study population including 49 (53.26%) on the left side and 43 (46.74%) on the right side (P > .05). The BCAs included 79 (85.87%) branchial cleft cysts, 11 (11.96%) branchial cleft sinuses, and 2 (2.17%) branchial cleft fistulae. Three (3.26%) BCAs were distributed in the head regions, 88 (95.65%) in the neck regions, and 1 (1.09%) in the thoracic cavity. Following surgery, lymphoepithelial tissue was detected in the histopathological examination in 83 (90.22%) BCAs. The hybrid branchial inclusion theory exhibited significantly higher accuracy in defining patho-anatomic characteristics of BCAs than the branchial apparatus, precervical sinus, thymopharyngeal, and inclusion theories (90.22, 9.78, 2.17, 0.00, and 0.00%; respectively) (P < .05).

Conclusion: The novel branchial node (BN) classification system based on the hybrid branchial inclusion theory appears to be superior to other classification systems in determining the patho-anatomy of BCAs.