cystic lymph node metastasis of papillary thyroid carcinoma

Diagnosis of cystic papillary thyroid carcinoma (PTC) lymph node metastasis at head neck region can be a challenge in the absence of known PTC history.

The congenital cystic lesions of head neck, especially thyroglossal duct cyst (TGDC) and branchial cleft cyst (BCC), are major differential diagnoses in this clinicopathological scenario.

The location of cyst and morphology of lining epithelium are critical clues for reaching correct diagnosis.

However it is not uncommon that the flattened bland epithelial lining can be seen in both cystic metastases and congenital cystic lesions.

Pax8 and TTF-1 are common markers in thyroid follicular epithelium.

IHC can help to diagnose cystic PTC metastasis to lymph node without prior malignancy history and cases of TGDC and BCC.

Both Pax8 and TTF-1 stainings highlighted the cyst lining in PTC metastatic lymph node, while they were negative in the lining of TGDC and BCC.

See also

 cystic cervical metastasis

Open references

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Case Rep Otolaryngol. 2015;2015:796358. doi : 10.1155/2015/796358
PMID: 26240771 Free

Paywall references

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J Laryngol Otol. 2013 Jul;127(7):724-7. doi : 10.1017/S0022215113001205
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