(18)F-DOPA PET/CT in the diagnosis and localization of persistent medullary thyroid carcinoma.
OBJECTIVE
To evaluate the performance of (18)F-L-dihydroxyphenylalanine ((18)F-DOPA) PET/CT in the detection of locoregional and distant medullary thyroid carcinoma (MTC) metastases and to compare imaging findings with histological data.


METHODS
We retrospectively evaluated 86 MTC patients with persistently high serum calcitonin levels after initial surgery who had undergone (18)F-DOPA PET/CT between January 2007 and December 2014 in two referral centres. They were followed up for at least 6 months after the PET/CT assessment. The results were compared with histological data or with the findings obtained during follow-up using a complementary imaging modality.


RESULTS
(18)F-DOPA PET/CT was positive in 65 of the 86 patients, corresponding to a patient-based sensitivity of 75.6 %. Distant metastatic disease (M1) was seen in 29 patients including 11 with previously unknown metastases revealed only by PET/CT. Among the 36 patients without distant metastatic spread, 25 had nodal involvement limited to the neck, and 10 of these 25 patients underwent reoperation. The lymph node compartment-based sensitivity of (18)F-DOPA PET/CT was 100 % in the two institutions but lesion-based sensitivity was only 24 %. Preoperative and postoperative median calcitonin levels were 405 pg/mL (range 128 - 1,960 pg/mL) and 259 pg/mL (range 33 - 1,516 pg/mL), respectively. None of the patients achieved normalization of serum calcitonin after reoperation.


CONCLUSIONS
(18)F-DOPA PET/CT enables early diagnosis of a significant number of patients with distant metastasis. It has a limited sensitivity in the detection of residual disease but provides high performance for regional analysis. A surgical compartment-oriented approach could be the approach of choice whatever the number of nodes revealed by (18)F-DOPA PET/CT.
Department of Nuclear Medicine, La Timone University Hospital, Aix-Marseille University, Marseille, France.|European Center for Research in Medical Imaging, Aix-Marseille University, Marseille, France.
Aurélien
A
Archier
Department of Biophysics and Nuclear Medicine, University Hospitals of Strasbourg, Strasbourg, France.
Céline
C
Heimburger
Department of Endocrine Surgery, Conception Hospital, Aix-Marseille University, Marseille, France.
Carole
C
Guerin
Department of Endocrinology, Conception Hospital, Aix-Marseille University, Marseille, France.
Isabelle
I
Morange
Department of Endocrine Surgery, Conception Hospital, Aix-Marseille University, Marseille, France.
Fausto F
FF
Palazzo
Department of Endocrine Surgery, Conception Hospital, Aix-Marseille University, Marseille, France.
Jean-François
JF
Henry
Department of Nuclear Medicine, Paul Strauss Cancer Center, Strasbourg, France.
Olivier
O
Schneegans
Department of Nuclear Medicine, La Timone University Hospital, Aix-Marseille University, Marseille, France.|European Center for Research in Medical Imaging, Aix-Marseille University, Marseille, France.
Olivier
O
Mundler
Department of Nuclear Medicine, La Timone University Hospital, Aix-Marseille University, Marseille, France.
Ahmad Esmaeel
AE
Abdullah
Department of Endocrine Surgery, Conception Hospital, Aix-Marseille University, Marseille, France.
Frédéric
F
Sebag
Department of Biophysics and Nuclear Medicine, University Hospitals of Strasbourg, Strasbourg, France.|Faculty of Medicine, ICube, UMR 7357 University of Strasbourg/CNRS and FMTS, Strasbourg, France.
Alessio
A
Imperiale
Department of Nuclear Medicine, La Timone University Hospital, Aix-Marseille University, Marseille, France. david.taieb@ap-hm.fr.|European Center for Research in Medical Imaging, Aix-Marseille University, Marseille, France. david.taieb@ap-hm.fr.|Inserm UMR1068 Marseille Cancerology Research Center, Institut Paoli-Calmettes, Marseille, France. david.taieb@ap-hm.fr.
David
D
Taïeb
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002116:Calcitonin / Q000378:metabolism; D018278:Carcinoma, Neuroendocrine / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D011379:Prognosis; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine; D002116:Calcitonin
18F-DOPA; Medullary thyroid carcinoma; Neuroendocrine tumours; Positron emission tomography