18F-FDG PET/CT and sentinel lymph node biopsy in the staging of patients with cervical and endometrial cancer. Role of dual-time-point imaging.
OBJECTIVE
Definitive staging for cervical (CC) and endometrial cancer (EC) takes place once surgery is performed. The aim of this study was to evaluate the role of PET/CT in detecting lymphatic metastasis in patients with CC and EC using dual-time-point imaging (DPI), taking the histopathological results of sentinel lymph node (SLN) and lymphadenectomy as the reference.


METHODS
A prospective study was conducted on 17 patients with early CC, and 13 patients with high-risk EC. The patients had a pre-operative PET/CT, MRI, SLN detection, and lymphadenectomy, when indicated. PET/CT findings were compared with histopathological results.


RESULTS
In the pathology study, 4 patients with CC and 4 patients with EC had lymphatic metastasis. PET/CT showed hypermetabolic nodes in 1 patient with CC, and 5 with EC. Four of these had metastasis, one detected in the SLN biopsy. Four patients who had negative PET/CT had micrometastasis in the SLN biopsy, 1 patient with additional lymph nodes involvement. The overall patient-based sensitivity, specificity, positive and negative predictive values, and accuracy of PET/CT to detect lymphatic metastasis was 20.0%, 100.0%, 100.0%, 87.9%, and 88.2%, respectively, in CC, and 57.1%, 88.9%, 66.7%, 84.2% and 80.0%, respectively, in EC. DPI showed higher retention index in malignant than in inflammatory nodes, although no statistically significant differences were found.


CONCLUSIONS
PET/CT has low sensitivity in lymph node staging of CC and EC, owing to the lack of detection of micrometastasis. Thus, PET/CT cannot replace SLN biopsy. Although no statistically significant differences were found, DPI may help to differentiate between inflammatory and malignant nodes.
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain. Electronic address: mmayoral@clinic.ub.es.
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Mayoral
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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Paredes
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain.
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B
Domènech
Clinic Institute of Gynaecology, Obstetrics and Neonatology, Hospital Clinic, Barcelona, Spain.
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Fusté
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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Vidal-Sicart
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain.
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Tapias
Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Clinic Institute of Gynaecology, Obstetrics and Neonatology, Hospital Clinic, Barcelona, Spain.
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Torné
Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Clinic Institute of Gynaecology, Obstetrics and Neonatology, Hospital Clinic, Barcelona, Spain.
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J
Pahisa
Pathology Department, Hospital Clinic, Barcelona, Spain; CRESIB (Centre de Recerca en Salut Internacional de Barcelona), Hospital Clinic, Barcelona, Spain.
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Ordi
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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Pons
Nuclear Medicine Department, Hospital Clínic, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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Lomeña
D000328:Adult; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary*; D016889:Endometrial Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D000071036:Sentinel Lymph Node / Q000000981:diagnostic imaging*; D021701:Sentinel Lymph Node Biopsy; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology
D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; C000615276:Fluorine-18
Cervical cancer; Cáncer de cérvix; Cáncer de endometrio; Dual-time-point imaging; Endometrial cancer; Ganglio centinela; Imagen dual-time-point; PET/CT; PET/TC; Sentinel lymph node