Thyroglossal duct cyst: A cytopathologic study of 26 cases

Abstract

Thyroglossal duct cyst (TDC), or embryologic remnants of thyroid gland, is a common congenital anomaly. TDC may cause a midline neck mass, which occasionally may become infected, and rarely gives rise to carcinoma. As a number of other nonneoplastic and neoplastic lesions can cause cystic masses in the neck, we explored the role of fine-needle aspiration (FNA) in making a preoperative diagnosis of TDC for a more accurate and timely clinical intervention. Twenty-six cases of TDC were identified from the cytopathology files of The Johns Hopkins Hospital in a 15-yr period (1990-2004). Material was obtained by FNA with or without radiologic (ultrasound) guidance. Smears were air-dried and stained with Diff-Quik, or wet-fixed and stained with Papanicolaou stain. Cytomorphologic characteristics were serially analyzed. Follow-up (tissue resection [n = 9] and clinical charts [n = 17]) was reviewed in all cases. Patients ranged in age from 8 to 83 yr (mean age, 55) with M:F ratio of 1.4:1. The size of the cyst ranged from 1.2 to 5 cm (mean 2.5 cm), as evaluated on radiological scans. The most common clinical presentation was a non-tender, mobile neck mass, which was painful on swallowing. Follow-up confirmed TDC in 18/26 cases (69%), whereas 8/26 cases resulted in various other benign lesions. During the same time period, 11/18 (61%) cases of surgically resected TDC were missed on prior FNA. Therefore, FNA showed a diagnostic sensitivity of 62% and a positive predictive value (PPV) of 69% for the diagnosis of TDC. The cytomorphologic features of TDC included the following: colloid (thick and fragmented, thin and watery, or mucinous), macrophages, lymphocytes, or predominantly neutrophils. The epithelium was ciliated columnar, metaplastic squamous or of mature squamous type. Thyroid epithelium was only rarely present (11%). FNA is only moderately sensitive for a preoperative evaluation of TDC. Cytomorphologic features are not unique; however, in the right clinicoradiologic setting should lead to an accurate diagnosis. Abundant colloid, most often with ciliated columnar epithelium, is the predominant cytopathologic finding. Thyroid epithelium is rarely identified. Differential diagnosis involves branchial cleft cyst, lymphoepithelial cyst, thyroid gland lesions, and lymphadenopathy (of various etiologies).

Dilemma in Managing Thyroglossal Duct Cyst Carcinoma

“…There is slightly more female: male ratio of 1.6: 1 [9]. The size of the mass is variable, but most are in the 1.2-5 cm range [10].…”

Papillary Carcinoma Arising in Thyroglossal Duct Cyst: A Retrospective Analysis (Cancer of the Thyroid or Primary Cancer of the Thyroglossal Cyst)

“…In some cases, for this same reason, due to these genetic errors, if the duct fails to obliterate, it may give rise to the development of a fistular passage (thyroglossal duct cyst). The thyroglossal duct cyst is the outcome of the persistence and of the cystic growth of the remnants of the thyroglossal tract [1] [2] [3]. Recently, specific follicular thyroid cell transcriptional factors have been identified which are responsible, selectively, for the thyroid genic expression of TTF-1, TTF-2 and PAX-8, each one of these genes is also expressed in stem cells and are different from the follicular thyroid cells, the association of these three factors is characteristic of the hormonogenetic thyroid cells [4] [5] [6].…”

A Decade of Experience of Management of Thyroglossal Duct Cyst in a Tertiary Care Hospital: Differentiation Between Children and Adults

“…The cyst accounts for approximately 70% of all congenital neck abnormalities [1]. Around 60% of the lesions are found before age 20 [2], in contrast to 7% [3] of the adult population who possess this anomaly.…”