Role of 18F-fluorodeoxyglucose positron emission tomography in preoperative assessment of cytologically indeterminate thyroid nodules.
ABSTRACT The objective of the study was to determine the diagnostic accuracy of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) in the preoperative diagnosis of thyroid nodules with indeterminate fine-needle aspiration biopsy results.
Forty-two consecutive patients with thyroid nodules with indeterminate cytological results participated in this study. Abnormal (18)F-FDG PET uptake was assessed visually and by measuring the maximum standardized uptake value (SUVmax) in thyroid topography. All these results were compared with the final pathological results.
The presence of focal uptake correlated with a greater risk of malignancy (P = 0.018). All 11 malignant nodules had focal uptake (sensitivity of 100%). Of the 31 patients with benign nodules, there were 19 with positive uptake (specificity of 38.7%). The pre-PET probability of cancer was 26.2% (11 of 42), and this probability increased to 36.7% after PET for those patients whose exam showed focal uptake (11 of 30). The preoperative use of (18)F-FDG PET would result in a significant reduction (39%, 12 of 31) in the number of thyroidectomies performed in patients with benign lesions. SUVmax could not improve this degree of accuracy. There was no correlation between thyroid nodule size and SUVmax value (P = 0.96). Patients with carcinomas were younger than patients with benign lesions (P = 0.048). There was no other clinical, laboratory, or ultrasonographic variable related to malignancy.
(18)F-FDG PET provides high sensitivity to malignant lesions and may be a potentially useful tool in the evaluation of thyroid nodules with indeterminate cytological findings. For these nodules the number of unnecessary thyroidectomies in a hypothetical algorithm using (18)F-FDG PET would be reduced by 39%.
Article: Fluorine-18-fluorodeoxyglucose positron emission tomography in the preoperative assessment of thyroid nodules in an endemic goiter area.[show abstract] [hide abstract]
ABSTRACT: The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the preoperative assessment of suspicious thyroid nodules. A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq (18)F-FDG. Standard uptake values (SUVs) were calculated. A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. (18)F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 +/- 2.2, 3.7 +/- 1.9, 1.6 +/- 0.3, 1.2 +/- 0.2, and 0.9 +/- 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used. Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. (18)F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded.Surgery 03/2003; 133(3):294-9. · 3.10 Impact Factor
Article: 18F-fluorodeoxyglucose positron emission tomography does not predict malignancy in thyroid nodules cytologically diagnosed as follicular neoplasm.[show abstract] [hide abstract]
ABSTRACT: The objective of this study was to evaluate the usefulness of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in predicting malignancy in thyroid nodules cytologically diagnosed as follicular neoplasm. A total of 46 patients with thyroid nodules larger than 1 cm in diameter cytologically diagnosed as follicular neoplasm at Asan Medical Center (Seoul, Korea) were included. FDG-PET images were taken in all patients before surgical resection, and the maximum standardized uptake value (SUVmax) of each nodule was measured. FDG-PET showed hypermetabolic activity of all nodules compared with normal thyroid tissue. Thirty-six patients underwent surgery, whereas 10 refused immediate operation. Fifteen patients had cancer: 11 with follicular and two each with Hürthle cell and follicular variants of papillary cancer. Twenty-one patients had benign nodules: 11 follicular adenomas, eight adenomatous hyperplasias, and two Hürthle cell adenomas. SUVmax did not differ significantly between malignant and benign nodules (3.6 +/- 3.5 vs. 3.4 +/- 3.2; P = 0.83) or among subtypes of benign nodules (P = 0.23). However, SUVmax differed significantly among subtypes of malignant nodules (P = 0.02). On FDG-PET, the glucose metabolic activities of benign thyroid follicular nodules were as high as those of malignant nodules. These findings suggest that FDG-PET has limited value for selecting candidates for surgery among patients cytologically diagnosed as follicular neoplasm.Journal of Clinical Endocrinology & Metabolism 06/2007; 92(5):1630-4. · 6.50 Impact Factor
[show abstract] [hide abstract]
ABSTRACT: Nine patients with suspicious thyroid nodules were studied with positron emission tomography (PET) following the administration of [18F]-2-deoxy-2-fluoro-D-glucose (FDG) prior to surgical excision. Three patients were ultimately determined to have papillary carcinoma, four were shown to have follicular adenomas, and two were proven to have multinodular goiters with dominant nodules. All three malignancies and four of the six benign lesions were easily detected visually as areas of increased FDG uptake. While visual analysis alone did not discriminate between the benign and malignant lesions, all three malignancies had dose uptake ratios (DURs) for FDG in excess of 8.5 while the DURs for benign lesions ranged between 1.9 and 6.3. The mean FDG DUR for the three papillary carcinomas (10.9 +/- 3.9; mean +/- SD) was significantly greater (p = 0.0019) than that of the six benign lesions (3.2 +/- 1.7). There was no significant difference between the FDG DUR for the follicular adenomas and the dominant nodules of multinodular goiters. Further research is needed to confirm the usefulness of PET in the differential diagnosis of thyroid nodules, and, in particular, whether or not PET can discriminate between benign and malignant follicular neoplasms.Thyroid 02/1993; 3(3):195-200. · 4.79 Impact Factor
Role of18F-Fluorodeoxyglucose Positron Emission
Tomography in Preoperative Assessment of Cytologically
Indeterminate Thyroid Nodules
Fernando M. Sebastianes, Juliano J. Cerci, Patricia H. Zanoni, Jose ´ Soares, Jr., Lilian K. Chibana,
Eduardo K. Tomimori, Rosalinda Y. A. de Camargo, Marisa Izaki, Maria Clementina P. Giorgi,
Jose ´ Eluf-Neto, Jose ´ Cla ´udio Meneghetti, and Maria Adelaide A. Pereira
Divisions of Endocrinology (F.M.S., P.H.Z., E.K.T., R.Y.A.d.C., M.A.A.P.) and Nuclear Medicine (J.J.C., J.S., L.K.C., M.I.,
M.C.P.G., J.C.M.), Hospital das Clı ´nicas da Faculdade de Medicina da Universidade de Sa ˜o Paulo, CEP 05403-000 Sa ˜o
Paulo, Brazil; and Department of Preventive Medicine (J.E.-N.), Faculdade de Medicina da Universidade de Sa ˜o Paulo,
CEP 01246-903 Sa ˜o Paulo, Brazil
accuracy of18F-fluorodeoxyglucose (18F-FDG) positron emission to-
indeterminate fine-needle aspiration biopsy results.
Methods: Forty-two consecutive patients with thyroid nodules with
indeterminate cytological results participated in this study. Abnor-
maximum standardized uptake value (SUVmax) in thyroid topogra-
phy. All these results were compared with the final pathological
Results: The presence of focal uptake correlated with a greater risk
of malignancy (P ? 0.018). All 11 malignant nodules had focal uptake
(sensitivity of 100%). Of the 31 patients with benign nodules, there
were 19 with positive uptake (specificity of 38.7%). The pre-PET
probability of cancer was 26.2% (11 of 42), and this probability in-
creased to 36.7% after PET for those patients whose exam showed
focal uptake (11 of 30). The preoperative use of18F-FDG PET would
result in a significant reduction (39%, 12 of 31) in the number of
thyroidectomies performed in patients with benign lesions. SUVmax
could not improve this degree of accuracy. There was no correlation
between thyroid nodule size and SUVmax value (P ? 0.96). Patients
with carcinomas were younger than patients with benign lesions (P ?
0.048). There was no other clinical, laboratory, or ultrasonographic
variable related to malignancy.
Conclusions:18F-FDG PET provides high sensitivity to malignant
lesions and may be a potentially useful tool in the evaluation of
thyroid nodules with indeterminate cytological findings. For these
nodules the number of unnecessary thyroidectomies in a hypothetical
algorithm using18F-FDG PET would be reduced by 39%. (J Clin
Endocrinol Metab 92: 4485–4488, 2007)
appropriate for differential diagnosis of benign and malig-
nant lesions in the preoperative evaluation of thyroid nod-
ules cytologically diagnosed as follicular neoplasm (1, 2).
However, a recent study has challenged the degree of accu-
racy of18F-FDG PET for this application (3). The aim of this
prospective study was to determine the diagnostic accuracy
nodules with indeterminate cytological results and the po-
tential of18F-FDG PET for reducing the number of thyroid-
ectomies performed on nodules that subsequently proved to
-FLUORODEOXYGLUCOSE (18F-FDG) positron emis-
sion tomography (PET) has been suggested as a tool
18F-FDG PET in the preoperative diagnosis of thyroid
Subjects and Methods
In a university hospital in Brazil, 42 patients (38 female) with inde-
terminate cytological results underwent hemithyroidectomy or total
histopathological results (Table 1). Incidentally found papillary micro-
carcinomas were not included in the analysis. Exclusion criteria were
uncontrolled diabetes mellitus, other known malignancies, pregnancy,
and abnormal TSH levels. The study was approved by the Ethical Board
of the Clinical Hospital of Sa ˜o Paulo University, and written informed
consent was obtained from all patients.
Fine-needle aspiration biopsy was performed by an experienced cy-
topathologist, and all aspirates were stained with Papanicolaou staining
and reviewed by two cytopathologists. Cytologically indeterminate pat-
of follicular neoplasm and also includes lesions that are suspect but not
diagnostic of papillary carcinoma (4). The criteria used for histopatho-
logical diagnosis of benign vs. malignant diseases were based on the
histological classification of thyroid tumors by the Word Health Orga-
The mean age was 45.3 ? 16.3 yr (range 18–80 yr). All patients
underwent thyroid ultrasonography, 50% of them having just one nod-
ule. The nodules had a mean maximum diameter in histopathological
exam of 3.0 ? 1.8 cm (range 0.4–8.5 cm). The interval between fine-
needle aspiration biopsy and18F-FDG PET was at least 17 d.
First Published Online August 7, 2007
sion tomography; ROI, region of interest; SUVmax, maximum standard
JCEM is published monthly by The Endocrine Society (http://www.
endo-society.org), the foremost professional society serving the en-
Printed in U.S.A.
The Journal of Clinical Endocrinology & Metabolism 92(11):4485–4488
Copyright © 2007 by The Endocrine Society
18F-FDG PET imaging
All patients fasted for at least 6 h. Their fasting glucose level was less
than 160 mg/dl. PET imaging acquisition started after a 60-min uptake
period after iv administration of 296–444 MBq (8–12 mCi) of18F-FDG.
The patients were instructed to rest comfortably between injection and
scanning. Images in two dimensions were captured by a GE Advance
PET scanner (General Electric Medical Systems Advance, Milwaukee,
WI). High-resolution images were taken with attenuation correction in
two or three bed positions, from the base of the skull to the middle
PET images were displayed as projections and in transaxial, coronal,
and sagittal tomographic sections. Visual inspection of the images was
performed independently by two experienced observers. These observ-
ers were not aware of the location of the nodule, ultrasonography, and
histopathological examination.18F-FDG PET-positive results were de-
standing out from the thyroid bed background. There was 100% agree-
ment between the two observers who analyzed these results.
Regions of interest (ROIs) were selected for quantification of18F-FDG
uptake from the visible lesions. When the thyroid nodule could not be
standard uptake values (SUVmax) were calculated.
A computer program (SPSS for Windows, version 13.0; SPSS Inc.,
Chicago, IL) was used for two-tailed statistical analysis. The level of
significance was set at 0.05. Correlations were determined using the
Spearman test. Analyses were also carried out using the Mann-Whitney
test, independent samples t test, and Fisher’s exact test, where appro-
priate, as shown in Results.
Final pathological diagnoses revealed 11 well-differenti-
ated thyroid carcinomas (26.2%), 22 adenomatous goiters
(52.4%), eight follicular adenomas (19.0%), and one thyroid-
itis (2.4%) (Table 1). Of the 11 patients with well-differenti-
TABLE 1. Clinical and ultrasonographic characteristics of patients and their histopathological and PET results
Classic V papillary carc
Follicular V papillary carc
Clear cell V papillary carc
WD carcinoma NOS
Follicular V papillary carc
Follicular V papillary carc
Follicular V papillary carc
Classic V papillary carc
Oxyphilic cell adenoma
Classic papillary carc
Patients 8, 15, and 40 had indeterminate cytological results with oxyphilic cells. Patient 7 had two nodules with indeterminate cytological
results (both were adenomatous nodules and both were FDG negative), and only the larger one was included in the analysis. Patient 37 was
multinodular; Carc, carcinoma; V, variant; WD, well differentiated; NOS, not otherwise specified.
aAccording to histopathological exam.
J Clin Endocrinol Metab, November 2007, 92(11):4485–4488Sebastianes et al. • PET for Thyroid Nodule Diagnosis
ated thyroid carcinomas, eight had papillary, two had fol-
licular, and one had a well-differentiated thyroid carcinoma
was associated with increased risk of malignancy (Fisher’s
(sensitivity of 100%). Of the 31 patients with benign nodules,
12 (39%) had negative uptake (Table 2). The pre-PET prob-
ability of cancer of 26% (11 of 42) rose to 37% (11 of 30) after
PET. SUVmax levels were not significantly greater in ma-
lignant than benign thyroid nodules (Mann-Whitney test,
P ? 0.069) and could not improve the accuracy of18F-FDG
PET beyond that obtained by the analysis of focal uptake
presence. All nodules without18F-FDG focal uptake had a
level of SUVmax of less than 3.7, except one patient with a
a level of SUVmax of 3.9.
Although the mean maximum diameter of the malignant
thyroid nodules (4.1 ? 2.6 cm) was greater than that of the
benign nodules (2.6 ? 1.2 cm), this difference was not con-
sidered to be statistically significant (t test, P ? 0.10). There
(Spearman, P ? 0.96). Regarding the benign nodules, size
was not associated with the SUVmax value (Spearman, P ?
0.57) nor the presence of focal uptake in18F-FDG PET (t test,
P ? 0.41). Of the clinical, laboratory, and ultrasonography
parameters, the only one that was associated with malig-
nancy was age. The mean age of patients with thyroid car-
cinomas was 37 ? 13.6 yr, lower than patients with benign
lesions, whose mean age was 48.2 ? 16.3 yr (t test, P ? 0.048).
Age, however, was not associated with either SUVmax
value (Spearman, P ? 0.70) or presence of focal uptake
(t test, P ? 0.34).
Four patients with benign thyroid lesions and positive
18F-FDG PET had incidental papillary microcarcinomas in
the same lobe (maximum diameters of 0.5, 0.5, 0.2, and 0.1
cm). All these cases were considered as false-positive results
by the analysis. Unexpected additional findings were found
in two of the 42 patients (4.8%): absence of18F-FDG uptake
in one lobe of the cerebellum (a cystic neoplasia in computed
in mediastinum in patient number 1 (the thorax computed
tomography with iv contrast was normal).
Our results confirm the findings of several studies (1–3,
6–11) that suggest that18F-FDG PET may have a very high
negative predictive value for detecting malignancy in the
preoperative evaluation of thyroid nodules (Table 2). From
more than 100 patients with malignant thyroid nodules eval-
uated in the literature, the only reported false-negative re-
sults are one case in a study that did not use a modern PET
camera (9) and seven nodules from the study by Mitchell et
al. (12), five being incidental microcarcinomas, one a papil-
lary carcinoma measuring 3.5 cm ? 2.6 cm in diameter
(SUVmax of 2.3), and one a renal carcinoma metastatic to
tomography, was the only one that included incidental mi-
crocarcinomas in the analysis. Of note, if the diagnostic cri-
teria adopted by Mitchell et al. were to be changed from an
SUVmax greater than 5.0 to an SUVmax greater than 0 (im-
plying some degree of nodule uptake), then the two major
carcinomas would have to be considered true-positive re-
sults, although the specificity among thyroid nodules with
indeterminate cytological results would be considerably re-
duced (Table 2).
In our study, 39% of the patients with benign thyroid
ies in literature had variable results (Table 2). In studies by
Kresnik et al. (2) and De Geus-Oei et al. (1), 56 and 66%,
results. It should be emphasized, however, that in the study
by Kresnik et al. (2), patients were from an iodine-poor area,
and that in the study from De Geus-Oei (1), only patients
with palpable thyroid nodules were selected and that their
size and ultrasonographic characteristics were not reported.
On the other hand, in the study by Kim et al. (3), all benign
thyroid nodules were18F-FDG avid and the only character-
istic associated with SUVmax value was nodule size. In our
study, however, the maximum nodule diameter was not
related to SUVmax value or focal uptake presence in the
subgroup of benign and malignant thyroid nodules was
The reasons for these differences are unclear and may be
related to a different pattern of gene expression between
benign nodules in different regions of the world because
malignant nodules are consistently FDG avid in all studies.
Variations in technique and selection of patients could also
be a reason. Prior studies reported increased glucose trans-
porter-1 protein immunostaining (13) and gene expression
TABLE 2. Summaries of the main studies assessing18F-FDG PET in preoperative evaluation of indeterminate thyroid nodules
No. of surgical
(in thyroid bed)
SUVmax ? 2.0
SUVmax ? 5.0
63 (17 of 27 patients)
56 (15 of 27 patients)
91 (21 of 23 nodules)
39 (9 of 23 nodules)
66 (25 of 38 patients)
0 (0 of 21 patients)
39 (12 of 31 patients)
0 (10 patients)Kresnik et al. (2)
Mitchell et al. (12)a
100 (1 of 1 nodule)c
0 (0 of 1 nodule)c
0 (6 patients, 7 nodules)
0 (15 patients)
0 (11 patients)
De Geus-Oei et al. (1)
Kim et al. (3)
FU, Focal uptake; NU, nodule uptake (defined as an SUVmax ? 0).
aThis study used18F-FDG PET-CT instead of18F-FDG PET-scan.
bThis is the number of thyroid nodules evaluated; it is not clearly stated how many of these nodules were present in the same patient.
cThis nodule was a papillary cancer measuring 3.5 ? 2.6 cm with an SUVmax of 2.3.
Sebastianes et al. • PET for Thyroid Nodule DiagnosisJ Clin Endocrinol Metab, November 2007, 92(11):4485–4488
(14) in thyroid cancer in relation to benign lesions, support-
ing the view that18F-FDG PET may be a useful tool when
evaluating thyroid nodules.
(1) that focal uptake presence should be the cornerstone in
any analysis of18F-FDG PET used in the evaluation of thy-
roid nodules, as shown in Table 2, although the specificity
of our findings in our study was only 39%. The value of
SUVmax depends on acquisition, reconstruction and ROI
in different centers. This may explain the different cutoffs of
SUV found in different studies (1, 2, 12).
The finding in our study of a patient with negative thyroid
focal uptake in a benign lesion but with an SUVmax of 3.9
(?3.7) was probably due to the coexistence of lymphocytic
thyroiditis resulting in diffuse thyroid uptake in18F-FDG
PET (16). However, even in patients in whom thyroiditis
coexists, it may be appropriate to recommend18F-FDG PET
because nine of the 11 patients with lymphocytic thyroiditis
in histopathological examinations did not show an alteration
of this exam.
Finally, papillary carcinoma was the malignancy most fre-
quently diagnosed in our study. This may be related to the
elevated daily ingestion of iodine that is common in Brazil
(17, 18), which could be responsible for substantially low-
ering the incidence of follicular as opposed to papillary thy-
roid carcinomas (19, 20).
In conclusion,18F-FDG PET provides a high negative pre-
dictive value in the preoperative evaluation of thyroid ma-
sensitivity to be the most important characteristic of a test
designed to determine which patients with indeterminate
cytological findings should undergo surgery, then18F-FDG
PET can be a useful tool in the evaluation of these nodules.
For these nodules the number of unnecessary hemithyroid-
ectomies in a hypothetical algorithm using
would be reduced by 39%.
We thank the staff from the Divisions of Endocrinology, Head and
Neck Surgery and Nuclear Medicine from Hospital das Clinicas da
Faculdade de Medicina da USP, Sa ˜o Paulo, Brazil, for their professional
assistance. We also thank Alexander A. de Lima Jorge for his sugges-
Received May 10, 2007. Accepted July 31, 2007.
Address all correspondence and requests for reprints to: Maria Ad-
elaide Albergaria Pereira, M.D., Division of Endocrinology and Metab-
olism, Hospital das Clı ´nicas, University of Sa ˜o Paulo Medical School,
AvenidaDrEne ´asdeCarvalhoAguiar,255,7thfloor,CEP05403-000Sa ˜o
Paulo (SP), Brazil.
Disclosure Statement: The authors have no conflict of interest.
1. De Geus-Oei LF, Pieters GFFM, Bonenkamp JJ, Mudde AH, Bleeker-Rovers
CP, Corstens FHM, Oyen WJG 200618F-FDG PET reduces unnecessary hemi-
thyroidectomies for thyroid nodules with indeterminate cytologic results.
J Nucl Med 47:770–775
2. Kresnik E, Gallowitsch HJ, Mikosch P, Stettner H, Igerc I, Gomez I, Kumnig
G, Lind P 2003 Fluorine-18-fluorodeoxyglucose positron emission tomogra-
phy in the preoperative assessment of thyroid nodules in an endemic goiter
area. Surgery 133:294–299
3. Kim JM, Ryu JS, Kim TK, Kim WB, Kwon GY, Gong G, Moon DH, Kim SC,
Hong SJ, Shong YK 200718F-Fluorodeoxyglucose positron emission tomog-
raphy does not predict malignancy in thyroid nodules cytologically diagnosed
as follicular neoplasm. J Clin Endocrinal Metab 92:1630–1634
4. Orell SR, Philips J 1997 The role of fine-needle biopsy in the investigation of
thyroid disease and its diagnostic accuracy. In: Orell SR, ed. Thyroid fine-
needle biopsy and cytological diagnosis of thyroid lesions. Vol 14. Basel,
5. DeLellis RA, Lloyd RV, Heitz PU, Eng C 2004 World Health Organization
classification of tumours. Pathology and genetics of tumours of endocrine
organs. Lyon, France: IARC Press
6. Adler LP, Bloom AD 1993 Positron emission tomography of thyroid masses.
7. Uematsu H, Sadato N, Ohtsubo T, Tsuchida T, Nakamura S, Sugimoto K,
Waki A, Takayashi N, Yonekura Y, Tsuda G, Saito H, Hayashi N, Yamamoto
K, Ishii Y 1998 Fluorine-18-fluorodeoxyglucose PET versus thallium-201 scin-
tigraphy evaluation of thyroid tumors. J Nucl Med 39:453–459
8. Wolf G, Aigner RM, Schaffler G, Schwarz T, Krippl P 2003 Pathology results
Nucl Med Commun 24:1225–1230
9. Joensuu H, Ahonen A, Klemi PJ 19888F-FDG-fluorodeoxyglucose imaging in
preoperative diagnosis of thyroid malignancy. Eur J Nucl Med 13:502–506
10. Sasaki M, Ichiya Y, Kuwabara Y, Akashi Y, Yoshida T, Fukumura T, Masuda
K 1997 An evaluation of FDG-PET in the detection and differentiation of
thyroid tumours. Nucl Med Commun 18:957–963
11. Bloom AD, Adler LP, Shuck JM 1993 Determination of malignancy of thyroid
nodules with positron emission tomography. Surgery 114:728–734
12. Mitchell JC, Grant F, Evenson AR, Parker JA, Hasselgren PO, Parangi S 2005
Preoperative evaluation of thyroid nodules with18FDG PET/CT. Surgery
13. Haber RS, Rathan A, Weiser KR, Pritsker A, Itzkowitz SH, Bodian C, Slater
G, Weiss A, Burstein DE 1998 GLUT-1 glucose transporter expression in
benign and malignant thyroid nodules. Thyroid 7:363–367
14. Matsuzu K, Segade F, Matsuzu U, Carter A, Bowden DW, Perrier ND 2004
Differential expression of glucose transporters in normal and pathologic thy-
roid tissue. Thyroid 14:806–812
15. Krak MC, Boellaard R, Hoekstra OS, Twisk JW, Hoekstra CJ, Lammertsma
AA 2005 Effects of ROI definition and reconstruction method on quantitative
outcome and applicability in a response monitoring trial. Eur J Nucl Med Mol
16. Yasuda S, Shohtsu A, Ide M, Takagi S, Takahashi W, Suzuki Y, Horiuchi M
17. Duarte GC, Tomimori EK, Boriolli RA, Ferreira JE, Catarino RM, Camargo
RY, Medeiros-Neto G 2004 Echographic evaluation of the thyroid gland and
urinary iodine concentration in school children from various regions of the
State of Sa ˜o Paulo, Brazil. Ar Qbras Endocrinol Metab 48:842–848
18. Rossi AC, Tomimori E, Camargo R, Medeiros-Neto G 2001 Searching for
iodine deficiency in schoolchildren from Brazil: the THYROMOBIL project.
19. Harach HR, Escalante DA, Day ES 2002 Thyroid cancer and thyroiditis in
Salta, Argentina: a 40-yr study in relation to iodine prophylaxis. Endocr Pathol
20. Williams ED, Doniach I, Bjarnason O, Michie W 1977 Thyroid cancer in an
iodide rich area: a histopathological study. Cancer 39:215–222
JCEM is published monthly by The Endocrine Society (http://www.endo-society.org), the foremost professional society serving the
J Clin Endocrinol Metab, November 2007, 92(11):4485–4488 Sebastianes et al. • PET for Thyroid Nodule Diagnosis