A 62-year-old woman presented with a suspected thyroid nodule. Past medical history revealed a cavernous sinus meningioma (World Health Organization, grade I), which was diagnosed in 1988 and treated with subtotal resection and external beam radiation therapy. The thyroid nodule was discovered incidentally on routine imaging studies. Subsequently, a transverse sonogram of the thyroid showed an apparent nodule in the posterior left lobe (Figure 1, arrows) measuring 1.2 × 1.1 × 0.5 cm. The nodule was noted to have a hypoechoic rim and small, punctate, echogenic foci that were suggestive of microcalcifications. The nodule was nonpalpable on physical examination; thyroid function tests were within normal limits.
An ultrasound-guided fine-needle aspiration was performed using a 22-gauge Franseen needle. The aspirate consisted of approximately 22 mL of cloudy, viscous fluid. Cytologic examination showed abundant, bland, mature squamous cells, singly and in small clusters (Figure 2), in a background of rarely encountered mixed inflammatory cells. Closer examination revealed numerous filamentous bacterial forms of varying lengths and associated amorphous debris (Figure 3). No thyroid epithelium or colloid was identified. Few areas showed densely stained, rigid, rectangular structures with cell walls that were suggestive of vegetable matter (Figure 4). Cultures obtained from the aspirated material were positive for Candida glabrata and lactobacilli.
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Pathologic Diagnosis: Oropharyngeal Diverticulum—Killian-Jamieson Diverticulum
Abstract
A 62-year-old woman with past medical history of cavernous sinus meningioma presented with an incidentally discovered apparent thyroid nodule. An ultrasound-guided fine-needle aspiration recovered mature squamous cells, filamentous bacteria, and vegetable matter, consistent with orophagyngeal contents. Subsequent clinical and further radiologic workup revealed a Killian-Jamieson diverticulum. This type of diverticulum is related to Zenker diverticulum and represents the outpouchings in the wall of the cervical esophagus in the vicinity of the thyroid gland. There are several case reports of Zenker diverticulum presenting radiographically as a thyroid nodule. To our knowledge, such radiographic presentation with cytopathologic findings has not been previously described in patients with Killian-Jamieson diverticulum.
On subsequent follow-up studies of our patient, an esophagram (barium swallow) demonstrated a 1-cm Killian-Jamieson diverticulum in the left lateral position. The diagnosis was subsequently confirmed by laryngoscopy and esophagoscopy.
Killian-Jamieson diverticulum is an uncommon entity related to the better-recognized Zenker diverticulum. These diverticula represent outpouchings in the wall of the hypopharynx or cervical esophagus, and are thought to develop at the site of anatomic muscle weakness. Zenker diverticulum develops in the posterior wall of the cricopharyngeus muscle. Killiam-Jamieson diverticulum arises in the anterolateral wall of the cervical esophagus adjacent to the cricoid cartilage. Both diverticula, particularly the Killian-Jamieson type, are located in the vicinity of the thyroid gland. Zenker diverticulum is 4 times more common than Killian-Jamieson diverticulum and is usually several times larger: the average size of Zenker diverticulum is 2.5 cm, whereas the average size of the Killian-Jamieson diverticulum is 1.4 cm.1,2
Although anatomically related, the 2 types of diverticula are clinically distinct. Based on a recent study, Zenker diverticula are symptomatic in 62% of cases.2 Common symptoms include dysphagia, regurgitation, cough, epigastric pain, chronic aspiration pneumonia, and halitosis. On the other hand, as in the case of our patient, Killian-Jamieson diverticula are asymptomatic in most patients (89%).1 Described symptoms are milder than in the cases of Zenker diverticulum and include dysphagia, cough, and epigastric pain.1 Symptomatic Killian-Jamieson and Zenker diverticula may be treated by external and endoscopic surgical approaches.
Although both Zenker and Killian-Jamieson diverticula are located in the vicinity of the thyroid gland, a radiographic appearance as a thyroid nodule is highly unusual. We found 4 case reports of Zenker diverticulum mimicking a thyroid nodule ultrasonographically.3–6 The distinguishing radiographic features of Zenker diverticulum from true thyroid nodules are discussed in a study by Komatsu et al.5 To the best of our knowledge, there are no cases described in the literature of Killian-Jamieson diverticulum presenting radiographically as a thyroid nodule.
Detection of oropharyngeal contents in the thyroid by fine-needle aspiration is a highly unusual occurrence and has not been previously encountered by us in a busy medical center. In addition to Killian-Jamieson and Zenker diverticula, the presence of oropharyngeal contents in the thyroid gland may evoke several other uncommon entities in the differential diagnosis, including a thyroglossal duct fistula and a third or fourth branchial fistula (piriform sinus fistula). Thyroglossal fistula appears as a midline tract, which may connect the thyroid gland and the foramen cecum at the base of the tongue, whereas piriform sinus fistula may connect the thyroid gland and the hypopharyngeal piriform sinus. Both types of fistulae usually present in the pediatric population and may be associated with an acute suppurative thyroiditis, and occasionally may manifest as a discrete thyroid mass.7,8 Although unusual in adults, piriform sinus fistulae presenting in later adulthood have been reported.9
Oropharyngeal diverticula and fistulae are highly unusual diagnoses for a lesion presenting as a solitary thyroid nodule. In general, common entities in the differential diagnosis of a solitary thyroid nodule include adenomatoid nodule and primary thyroid neoplasm (papillary, follicular, anaplastic, and medullary types).10 Metastatic lesions to the thyroid are rare. Primary neoplasms that metastasize to the thyroid include kidney, breast, lung, and stomach. Although our patient had a history of intractable meningioma, the metastasis of such tumor to the thyroid would be an exceedingly rare event.
In conclusion, oropharyngeal diverticulae and developmental fistulae may rarely present radiographically as thyroid lesions. Such lesions should be considered in the differential diagnosis of a suspected solitary thyroid mass with mature squamous cells on fine-needle aspiration.
References
The authors have no relevant financial interest in the products or companies described in this article.
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