Monitoring thyroglobulin in a sensitive immunoassay has comparable sensitivity to recombinant human TSH-stimulated thyroglobulin in follow-up of thyroid cancer patients

Robert C. Smallridge, Shon E. Meek, Melissa A. Morgan, Geoffrey S. Gates, Thomas P. Fox, Stefan Grebe, Vahab Fatourechi

Research output: Contribution to journalArticle

123 Scopus citations

Abstract

Context: Most thyroglobulin (Tg) assays have a sensitivity of 0.5-1 ng/ml. A minority of patients with undetectable T4-suppressed Tg levels have a recombinant human TSH (rhTSH)-stimulated Tg above 2 ng/ml and identifiable residual disease. Objective: The objective was to determine whether a Tg assay with improved sensitivity could eliminate the need for rhTSH stimulation when baseline Tg is below 0.1 ng/ml. Design: A retrospective study of two academic endocrine practices was conducted. Population: A total of 194 patients undergoing rhTSH stimulation participated in the study. Results: Of the 80 patients with Tg below 0.1 ng/ml, two (2.5%) had rhTSH-stimulated Tg above 2 ng/ml. One other patient with stimulation to 0.3 ng/ml and negative 123I scan had an ultrasound-detected malignant lymph node resected. None had 131I/123I imaging after rhTSH stimulation suggestive of local recurrence or distant metastasis. If T4- suppressed Tg was 0.1-0.5 or 0.6-2.0 ng/ml, rhTSH Tg was above 2 ng/ml in 24.2 and 82.4%, respectively. Conclusions: Patients with differentiated thyroid carcinoma and a T4-suppressed serum Tg below 0.1 ng/ml rarely have a rhTSH-stimulated Tg above 2 ng/ml, and none of these patients had 131I or 123I imaging after rhTSH stimulation suggestive of local recurrence or distant metastasis. We recommend monitoring such patients with a T4-suppressed Tg level and periodic neck ultrasonography. An increase in T4-suppressed serum Tg to a detectable level or the appearance of abnormal lymph nodes by physical or ultrasound exam should prompt further investigation.

Original languageEnglish (US)
Pages (from-to)82-87
Number of pages6
JournalJournal of Clinical Endocrinology and Metabolism
Volume92
Issue number1
DOIs
StatePublished - Jan 2007

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Biochemistry
  • Endocrinology
  • Clinical Biochemistry
  • Biochemistry, medical

Fingerprint Dive into the research topics of 'Monitoring thyroglobulin in a sensitive immunoassay has comparable sensitivity to recombinant human TSH-stimulated thyroglobulin in follow-up of thyroid cancer patients'. Together they form a unique fingerprint.

  • Cite this