Therapeutic doses of iodine-131 reveal undiagnosed metastases in thyroid cancer patients with detectable serum thyroglobulin levels

Journal Article · Tue Dec 01 04:00:00 EST 1987 · J. Nucl. Med.; (United States)

OSTI ID:5721364

Pacini, F; Lippi, F; Formica, N; Elisei, R; Anelli, S; Ceccarelli, C; Pinchera, A

Serum thyroglobulin (Tg) measurements in patients with treated differentiated thyroid cancer are usually well correlated with the presence or absence of residual or metastatic thyroid tissue. However, it is not rare to find a patient with detectable serum Tg levels but negative /sup 131/I whole-body scan (WBS) and no evidence of disease activity. To clarify the reason for this discrepancy, we decided to perform the WBS after the administration of a therapeutic dose of /sup 131/I in 17 consecutive patients in whom serum Tg was detectable while the WBS performed with a 5 mCi tracer dose was negative (12.6% of 135 patients studied with both WBS and serum Tg). The result of this study demonstrated that after this procedure the WBS became positive for significant residual or metastatic areas of radioiodine uptake in all patients but one. Such data indicate that in our patients the presence of circulating Tg is not a false-positive Tg result, but is due to the presence of residual or metastatic tissue that is not detected in the conventional WBS, that can be visualized using therapeutic doses. Preliminary follow-up data indicate that this procedure may also have therapeutic effect, although the relevance of this aspect remains to be established.

• Research Organization: Univ. of Pisa, Italy
• OSTI ID: 5721364
• Journal Information: J. Nucl. Med.; (United States), Journal Name: J. Nucl. Med.; (United States) Vol. 28:12; ISSN JNMEA
• Country of Publication: United States
• Language: English

Related Subjects

550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
550604* -- Medicine-- Unsealed Radionuclides in Therapy-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
COUNTING TECHNIQUES
DAYS LIVING RADIOISOTOPES
DIAGNOSIS
DISEASES
ENDOCRINE GLANDS
GLANDS
GLOBULINS
INTERMEDIATE MASS NUCLEI
IODINE 131
IODINE ISOTOPES
ISOTOPES
MEDICINE
METASTASES
NEOPLASMS
NUCLEAR MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PATIENTS
PROTEINS
RADIOISOTOPE SCANNING
RADIOISOTOPES
RADIOLOGY
RADIOTHERAPY
THERAPY
THYROGLOBULIN
THYROID