PT - JOURNAL ARTICLE AU - Yana Garger AU - Matthew Winfeld AU - Kent Friedman AU - Manfred Blum TI - SPECT/CT alters management by revealing hyperemia of inflammation as the cause of false-positive I-131 whole-body scans in post-thyroidectomy thyroid cancer patients DP - 2012 May 01 TA - Journal of Nuclear Medicine PG - 2080--2080 VI - 53 IP - supplement 1 4099 - http://jnm.snmjournals.org/content/53/supplement_1/2080.short 4100 - http://jnm.snmjournals.org/content/53/supplement_1/2080.full SO - J Nucl Med2012 May 01; 53 AB - 2080 Objectives To show that I-131 SPECT/CT will reveal that false positive results on whole-body scans (WBS) after thyroidectomy for thyroid cancer may be due to hyperemia unassociated with the cancer. Methods We perform WBS on women of child-bearing age while they are menstruating to be certain they are not in early pregnancy before HCG is positive. The increased uterine blood flow/inflammation leads to focal accumulation of I-131 in the uterus. Similar inflammatory-derived uptake in the pelvis may be seen at sites of an intrauterine device and also uterine fibroids (1). Other frequent sources of false-positive uptake on WBS include dental/gingival inflammation, local infection and joint inflammation. To better interpret 40 WBS of 38 thyroidectomized thyroid cancer patients, 40 I-131 SPECT/CT scans were performed (2). Since then, we performed 32 additional SPECT/CT for WBS that had cryptic focal radioactivity. Results 8/40 had uterine corpus and or cervical uptake, and 8/40 had gingival uptake. Other sites included the thymus, gall bladder, renal cyst, recto-sigmoid colon, urinary bladder, and soft tissue infection. The additional 38 expanded and confirmed our findings. Conclusions Physiologic hyperemia of inflammation may cause a false-positive WBS. I-131 SPECT/CT is powerful to differentiate hyperemia and thyroid cancer. By excluding metastatic disease, one can properly prognosticate outcome and avoid unnecessary harmful treatment