HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Regalbuto, C. Articles by Pezzino, V. Search for Related Content PubMed PubMed Citation Articles by Regalbuto, C. Articles by Pezzino, V.

False-Positive Findings on ¹³¹I Whole-Body Scans Because of Posttraumatic Superficial Scabs

¹ Department of Internal Medicine and Endocrine and Metabolic Diseases, Garibaldi Hospital, University of Catania, Catania, Italy

ABSTRACT

Nonspecific ¹³¹I uptake may affect both the specificity and the accuracy of whole-body scanning (WBS) performed after ¹³¹I administration in the follow-up of thyroid carcinoma after thyroidectomy. We report a newly identified cause of false-positive WBS findings: posttraumatic superficial scabs. Methods: Four patients who underwent thyroidectomy for differentiated thyroid carcinoma were studied after therapeutic administration of 3,700 MBq ¹³¹I. Results: WBS revealed an area of uptake in the lower limbs, in a site corresponding to a slight abrasion of the skin that had incidentally occurred between a few hours before and 24 h after radioiodine administration. In 2 patients, a radioiodine concentration in the scab was shown by the disappearance of the radioactivity in the leg after removal of the scab and by detection of radioactivity in the collected material. Conclusion: Posttraumatic superficial scabs may be a cause of false-positive WBS findings. High ¹³¹I doses, although providing increased sensitivity, may also increase the number of false-positive results.

Key Words: thyroid carcinoma • ¹³¹I • whole-body scan • false-positive • scab