False-Positive 131I Uptake After Transareola Endoscopic Thyroidectomy in a Patient With Papillary Thyroid Carcinoma

Abstract

False-positive 131 I accumulation in patients with thyroid carcinoma could be due to various etiologies. Herein, we reported a case of papillary thyroid carcinoma in a 36-year-old woman. She underwent a 131 I radiotherapy after a transareola endoscopic total thyroidectomy. 131 I scintigraphy showed a high uptake in the thyroid bed. Surprisingly, increased activity was also noted in the right areola area. This activity corresponding to the entry site of endoscope revealed on the following SPECT/CT.

False-positive radioiodine uptake after radioiodine treatment in differentiated thyroid cancer

“…Overall, the literature showed 145 case reports and two series regarding false-positive 131 uptake after RIT For the reasons stated above, we excluded 129 papers, considering only those in which SPECT/CT was performed. A total of 18 papers were thus included: 1 series [17] and 17 case reports [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. The series reported 23 cases of falsepositive results: 15 in the chest, six in the pelvis, one in the cranium, and one in the abdomen.…”

“…The series reported 23 cases of falsepositive results: 15 in the chest, six in the pelvis, one in the cranium, and one in the abdomen. Overall, 20 cases regarded radioiodine uptake in the chest: 11 in the lung (mainly inflammatory), four on the chest bones or on soft tissue due to inflammation/trauma, one in the thymus, one mesenchymal tumor and the rest in not well-characterized sites [17][18][19][20][21]34]. A total of 15 cases regarded uptake in the abdomen/pelvis: six in the kidney (cysts), five in the ovary (teratoma, benign cysts and malignant disease), two in the uterus and the others in not well-characterized sites [22][23][24][25][26][27][28][29].…”

“…For example, the explanation for the false-positive was easily arrived at not only through SPECT/CT, but also due to the patient's personal history. Two cases were due to post-surgical metallic clips, one case was due to a breast implant, and one case was due to recent scarring caused by the transareolar approach employed for the thyroidectomy [21,34]. In many cases, accumulation of radioiodine was found in anatomic lesions without there being any apparent reasonable explanation, and the cause was simply classified as "undetermined".…”

Unexpected false-positive uptake of 131I on the right eye in a patient with differentiated thyroid cancer: a case description

“…To date, there have been many case reports of false-positive 131 I whole-body scans ( 4 - 8 ), but very few reports have detailed the false-positive uptake of 131 I in the eyes. As far as we know, eye metastasis from thyroid cancer is rare ( 9 ).…”

Diagnosis and Treatment of Acute Pleural Effusion following Radioiodine Remnant Ablation Post Lobectomy for Thyroid Cancer

“…Owing to the improvement of diagnostic accuracy by incorporating hybrid SPECT/CT in the last two decades, most causes of 131 I uptake in rare clinical settings could be identified, with incremental value in the management of patients with DTC, as previously described by our group [ 23 , 24 ]. Recently, extremely scarce cases of solitary breast metastasis from DTC and transplantation in endoscopic thyroidectomy were reported [ 25 , 26 ]. Furthermore, 131 I-avid malignancies beyond DTC have been identified by 131 I WBS with or without SPCET/CT, such as primary lung cancer, gastric adenocarcinoma, metastatic salivary gland tumor, and papillary meningioma [ 27 ].…”