Clinical relevance of single-photon emission computed tomography/computed tomography of the neck and thorax in postablation (131)I scintigraphy for thyroid cancer

J Clin Endocrinol Metab. 2009 Jun;94(6):2075-84. doi: 10.1210/jc.2008-2313. Epub 2009 Mar 10.


Context: In patients with differentiated thyroid carcinoma, postablation (131)I scintigraphy aims to detect residual neck disease and distant metastases, usually found in lungs and bones. New hybrid single-photon emission computed tomography/computed tomography (SPECT-CT) cameras that permit functional and anatomical image fusion may improve its clinical relevance.

Objective: Our objective was to test the added value of neck and thorax SPECT-spiral CT to whole-body scan (WBS) in postablation (131)I scintigraphy.

Design and setting: This was a single-referral-center prospective study with a median follow-up of 21 months.

Patients and methods: Postablation (131)I WBS and neck and thorax SPECT-CT were performed in 55 consecutive patients treated in 2006. WBS and SPECT-CT data were blindly reviewed, scored negative (benign), positive (malignant), or indeterminate and were correlated to the patient outcome.

Results: At patient level, WBS and SPECT-CT were negative in 67 and 78% of patients, positive in 4 and 15%, and indeterminate in 29 and 7%, respectively. Overall, nine patients (16%) presented treatment failure (persistent or recurrent disease) 1-16 months after radioiodine ablation. In the 16 patients with indeterminate WBS, negative SPECT-CT ruled out suspicion of disease in nine of nine patients, and positive SPECT-CT confirmed malignant lesions in four of five patients. Positive SPECT-CT predicted treatment failure better than positive WBS (McNemar's test, P = 0.03).

Conclusions: This study demonstrates the complementary role of neck and thorax SPECT-CT to WBS in postablation (131)I scintigraphy. Because SPECT-CT allows one to confirm or to rule out residual disease in most cases where WBS remains indeterminate, we recommend its use when available.

Publication types

  • Evaluation Study

MeSH terms

  • Ablation Techniques / methods
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma / diagnostic imaging*
  • Carcinoma / surgery
  • Child
  • Female
  • Humans
  • Iodine Radioisotopes*
  • Male
  • Middle Aged
  • Neck / diagnostic imaging*
  • Postoperative Complications / diagnostic imaging
  • Prognosis
  • Retrospective Studies
  • Thorax / diagnostic imaging*
  • Thyroid Neoplasms / diagnostic imaging*
  • Thyroid Neoplasms / surgery
  • Tomography, Emission-Computed, Single-Photon*
  • Whole Body Imaging / methods
  • Young Adult


  • Iodine Radioisotopes