Giant Cervicomediastinal Thyroglossal Duct Cyst Presenting as Vocal Fold Immobility: A Case Report

November 12, 2026 Dr. Michael Lee – Health Editor Health

A 59-year-old man underwent successful surgical removal of a giant 11-centimeter cervicomediastinal cyst, resolving chronic hoarseness and airway compression, according to a case report.

The rare mass, which extended from the neck to the aortic arch, was initially mistaken for a parathyroid cyst before histological analysis showed features compatible with a thyroglossal duct cyst (TGDC).

Key Clinical Takeaways:

  • Giant TGDCs can extend into the mediastinum, potentially mimicking other thoracic masses and complicating preoperative diagnosis.
  • Transcervical excision remains a viable surgical approach for large cysts extending to the aortic arch, provided anatomy is favorable and thoracic surgical support is available.
  • Patients presenting with unexplained vocal fold immobility and airway displacement require thorough cross-sectional imaging to rule out rare developmental neck anomalies.

Clinical Presentation and Diagnostic Challenges

The patient first sought medical attention in February 2020, reporting shortness of breath and hoarseness. Clinical evaluation revealed left vocal fold immobility, which indicated dysfunction of the left recurrent laryngeal nerve. A computed tomography (CT) scan performed in June 2020 identified a water-density cyst measuring 11 centimeters in craniocaudal extent. The mass caused significant anatomical shifts, displacing the trachea to the right and compressing the brachiocephalic veins.

Because the cyst was inseparable from the left thyroid lobe and yielded clear fluid during fine-needle aspiration, clinicians initially suspected a non-functioning parathyroid cyst. The rarity of mediastinal involvement for TGDCs often leads to diagnostic confusion with thymic, bronchogenic, or lymphatic cysts. Establishing an accurate diagnosis in such cases is essential for determining the appropriate surgical access, as mediastinal extension can necessitate more invasive procedures like sternotomy.

Surgeons Performed Intact Excision Through Neck Incision

In August 2020, surgeons performed an intact excision through a Kocher collar incision. This approach required careful dissection of the left recurrent laryngeal nerve. Because the thoracic surgeon was prepared for a potential sternotomy, the medical team maintained a high level of readiness for complications, though the lesion was successfully delivered through the neck incision.

Following the procedure, the patient was discharged on the second postoperative day. Histological examination of the specimen showed a largely denuded, inflamed, and sclerotic cyst wall with adjacent thyroid parenchyma, compatible with a TGDC. By May 2025, the patient remained well, and follow-up examinations confirmed the full recovery of his left vocal fold function.

Analysis of Mediastinal TGDC Cases

The report shows that TGDCs, while common as midline neck anomalies near the hyoid bone, are difficult to treat when they descend into the mediastinum.

Reviewing eight previously published cases, the authors said that lesions associated with the thyroid gland or thyroid bed are often amenable to cervical excision. The current case reinforces the importance of considering TGDCs in the differential diagnosis of cervicomediastinal masses, even when clinical features suggest other pathologies.

While the patient has recovered effectively, the study notes that radiological confirmation of long-term absence of recurrence was not possible as the patient declined further CT imaging. The outcome shows that complex neck masses involving the thoracic inlet require specialized surgical planning.

Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.

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