Abstract
OBJECTIVE
1) Report a case series of unusual sites of metastatic papillary thyroid cancer. 2) Correlate these findings with more aggressive disease. 3) Review the current literature for descriptions of typical and atypical patterns of papillary thyroid cancer metastases.
METHOD
In this retrospective case series performed at a tertiary care center, four patients treated for papillary thyroid cancer between September 2009 and February 2010 were found to have unusual sites of metastases. We report on this series and perform a review of the current literature regarding typical sites of spread.
RESULTS
Metastatic papillary thyroid cancer was found in the following locations: 1) within the sternocleidomastoid muscle, 2) occipital skin, skull, dura, and within the internal jugular vein, 3) retropharynx, and 4) in the right atrium. Review of current literature demonstrated the most common locations of regional metastases are level VI (77%), followed by level III (69%), level IV (66%), and level II (46%) of the deep cervical chain.
CONCLUSION
Our patients novel sites of metastatic disease have not been depicted in previous reports. In our series all patients with unusual metastatic disease had a more aggressive course, more aggressive histology, less iodine avidity, and had worse outcomes. Although this disease most often spreads to the deep cervical chain, atypical sites of distant metastases should always be considered in patients presenting with a new mass who have known history of papillary thyroid cancer.