Introduction: Although branchial cysts may present as asymptomatic swellings, about one-third present acutely due to inflammation. The use of fine-needle aspiration biopsy (FNAB) and computerized tomography (CT) is controversial. The treatment of inflamed cysts is also controversial.

Aims: To compare the findings of FNAB and CT between cases of branchial cysts presenting as an asymptomatic swelling, and those presenting acutely due to inflammation, and to examine the management of infected cysts.

Materials and methods: Retrospective review of the medical records of 39 adult patients with histologically proven branchial cysts treated by the senior author (C.V.T.) between 1994 and 2003.

Results: Twenty-eight patients presented with an asymptomatic swelling. Eleven presented acutely with inflammation. A higher incidence of indeterminate fine needle aspirates and atypical CT features were found in the inflamed group. Initial treatment in the infected group consisted of intravenous antibiotics, followed by aspiration or surgical exploration in non-resolving cases. Interval excision after six weeks was performed in all inflamed cases without complication.

Conclusions: FNAB is recommended in all cystic neck lumps to rule out malignancy, but may be inconclusive, especially in inflamed cysts. Inflamed cysts are best treated with intravenous antibiotics, with or without aspiration or incision and drainage, followed by interval excision.