Background: Fibromatosis colli (FC), also known as sternocleidomastoid tumor of infancy, is a benign spindle cell lesion of the sternocleidomastoid muscle. It usually is seen in the first few weeks of life and is the most common cause of a neck mass in the perinatal period. Although FC may lead to congenital muscular torticollis requiring surgical intervention, if the diagnosis of FC is certain, the usual initial treatment option is conservative management.
Objective: To show the utility of fine-needle aspiration in the diagnosis of FC.
Patients: Five cases in which fine-needle aspiration was used in the evaluation of patients with FC were identified retrospectively by a search of the cytopathology files of the State University of New York Health Science Center at Syracuse and the Virginia Commonwealth University, Medical College of Virginia, Richmond.
Results: Fine-needle aspiration yielded an initial diagnosis of FC in 4 of the 5 cases. Smears made from the aspirated material were of low cellularity, but showed a characteristic population of spindle-cell fibroblasts. In addition to these fibroblasts, a variable amount of degenerating skeletal muscle was present in the background.
Conclusion: With the collaborative efforts of otolaryngologists and pathologists, fine-needle aspiration can be used to confirm a clinical diagnosis of FC while avoiding the expense and risk of open biopsy.