68Ga-DOTA-NOC: a new PET tracer for evaluating patients with bronchial carcinoid.
BACKGROUND
Conventional imaging techniques [computed tomography (CT), ultrasound, magnetic resonance] and somatostatin receptor scintigraphy are often insufficient to make a conclusive diagnosis of bronchial carcinoid (BC). PET is commonly used for the assessment of lung cancer but 18F-fluorodeoxyglucose, the most frequently used PET tracer, presents a low sensitivity for the detection of neuroendocrine tumours (NETs). New PET radiopharmaceuticals such as 68Ga-DOTA peptides, which directly bind to somatostatin receptors and are usually expressed on NET cell surfaces, have been reported to be superior to both morphological and somatostatin receptor scintigraphy imaging for gastroenteropancreatic NETs. However, their role in BC has never been evaluated. Our aim is to evaluate the role of 68Ga-DOTA-NOC (68Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-Nal3-octreotide) PET for the assessment of BC patients.


METHODS
Ten patients with pathologically proven well-differentiated BC and one patient with highly suggestive CT images for BC were studied by 68Ga-DOTA-NOC PET/CT. PET findings were compared with clinical follow-up, pathology and contrast-enhanced CT findings.


RESULTS
68Ga-DOTA-NOC PET/CT detected at least one lesion in nine of 11 patients and was negative in two. PET/CT and contrast-enhanced CT were discordant in eight of 11 patients, whereas in only three patients both provided similar results. PET/CT detected a higher number of lesions in five patients and excluded malignancy at sites considered positive on CT in three of 11; follow-up confirmed PET/CT findings in all patients. In PET/CT-positive patients, the mean maximal standardized uptake value was 25.9 [4.4-60.5]. On a clinical basis, PET/CT provided additional information in nine of 11 patients leading to the changes in the clinical management of three of nine patients.


CONCLUSIONS
PET/CT with Ga-DOTA-NOC was useful in BC patients because it led to a better evaluation of the extent of the disease.
Ambrosini
Valentina
V
Department of Nuclear Medicine, Policlinico 'S. Orsola-Malpighi' Hospital, Bologna, Italy.
Castellucci
Paolo
P
Rubello
Domenico
D
Nanni
Cristina
C
Musto
Alessandra
A
Allegri
Vincenzo
V
Montini
Gian Carlo
GC
Mattioli
Sandro
S
Grassetto
Gaia
G
Al-Nahhas
Adil
A
Franchi
Roberto
R
Fanti
Stefano
S
D000368:Aged; D000369:Aged, 80 and over; D001345:Autoradiography; D001984:Bronchial Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D002276:Carcinoid Tumor / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D015282:Octreotide / Q000031:analogs & derivatives; D009942:Organometallic Compounds; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed
C504894:68Ga-DOTANOC; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; C094279:indium-111-octreotide; D015282:Octreotide