Click the arrow to see the next slide with the correct interpretation.
Young Male with Left-Sided Neck Mass
This case features a young male presenting with a left-sided neck mass, ultimately diagnosed with papillary thyroid cancer arising within a thyroglossal duct cyst (TGDC) with hypervascular metastatic lymph nodes.
Imaging overview:
Axial and sagittal contrast-enhanced CT of the neck demonstrates a solid and cystic enhancing lesion in the prehyoid and prelaryngeal region with foci of calcification. Multiple hypervascular lymph nodes, defined by attenuation greater than 120 Hounsfield units, are also identified, consistent with metastatic nodal disease.
Clinical insight:
Thyroid carcinoma arising within a thyroglossal duct cyst is a rare occurrence, estimated to develop in less than 1% of TGDCs. The presence of a solid component, mural nodule, or calcifications within a cystic midline neck mass on CT or MRI should raise suspicion for carcinoma within a TGDC and prompt further workup. Hypervascular nodal metastases are uncommon and, when present, are most frequently associated with thyroid cancer, neuroendocrine metastases, or Castleman’s disease. Recognizing these imaging features is critical to avoiding misclassification of a malignant midline neck mass as a simple benign cyst.
Case courtesy of Siddhartha Gaddamanugu, MD,
University of Alabama at Birmingham