Interesting Image

I-131 Avid Tumor Thrombus in a Case of Poorly Differentiated Thyroid Cancer


  • Sana Munir Gill
  • Aamna Hassan
  • Humayun Bashir
  • Waqas Shafiq

Received Date: 08.11.2022 Accepted Date: 22.01.2023 Mol Imaging Radionucl Ther 2023;32(2):178-180 PMID: 37337877

Intravenous tumor extension is a well-recognized phenomenon occurring in various malignancies but is a relatively rare entity in thyroid carcinoma. In patients with poorly differentiated thyroid cancer (pDTC), I-131 avid superior vena cava tumor (SVC) thrombus at initial presentation is infrequent and potential life threatening. Tumor thrombus can form either due to direct vascular extension of the primary mass or by hematogenous spread. Hybrid nuclear imaging can differentiate the two entities, which can impact the treatment plan of the patient. We present images of an interesting case of evolution of SVC thrombus in a 46-year-old woman with diagnosed pDTC over the span of two years.

Keywords: I-131 avid tumor thrombus, SPECT/CT, poorly differentiated thyroid cancer


Informed Consent: Written consent was taken from the patient.

Peer-review: Externally and internally peer-reviewed.

Authorship Contributions

Surgical and Medical Practices: A.H., H.B., W.S., Concept: A.H., H.B., Design: S.M.G., A.H., Data Collection or Processing: S.M.G., A.H., Analysis or Interpretation: A.H., H.B., Literature Search: S.M.G., Writing: A.H., H.B., W.S.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.


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