FDG-PET/CT for the preoperative lymph node staging of invasive bladder cancer.
BACKGROUND
Locoregional lymph node metastasis is an important prognostic factor in patients with bladder cancer. Multimodal treatment, depending on preoperative stage, may improve survival. The standard imaging modalities for staging (computed tomography [CT] or magnetic resonance imaging [MRI]) have an accuracy range of 70-90% for lymph node staging. A more accurate preoperative diagnostic test could improve survival rates even more.


OBJECTIVE
To determine whether the use of 2-deoxy-2 [F] fluoro-D-glucose (FDG) positron emission tomography (PET) in combination with CT (FDG-PET/CT) can increase the reliability of preoperative lymph node staging in patients with nonmetastatic invasive bladder cancer (T2 or higher, M0) or recurrent high-risk superficial disease (T1G3 with or without Tis, M0).


METHODS
Fifty-one patients underwent a preoperative FDG-PET/CT between April 2004 and December 2007. Independent of the result for lymph node status, all patients underwent a radical cystectomy and an extended lymphadenectomy. The FDG-PET/CT and CT results were compared with the definitive pathologic results.


METHODS
Among the 51 patients, 13 patients had metastatically involved locoregional lymph nodes, diagnosed on histopathology. In six patients, these nodes demonstrated increased FDG uptake on PET. In seven patients, PET/CT did not diagnose the positive lymph nodes. PET/CT was false positive in one patient.


CONCLUSIONS
For the diagnosis of node-positive disease, the accuracy, the sensitivity, and the specificity of FDG-PET/CT were 84%, 46%, and 97%, respectively. When analysing the results of CT alone, there was accuracy of 80%, sensitivity of 46%, and specificity of 92%. The use of FDG-PET/CT is hampered by technical limitations.


CONCLUSIONS
We found no advantage for combined FDG-PET/CT over CT alone for lymph node staging of invasive bladder cancer or recurrent high-risk superficial disease.
Swinnen
Greet
G
Department of Urology, AZ Groeninge, Kortrijk, Belgium.
Maes
Alex
A
Pottel
Hans
H
Vanneste
Alain
A
Billiet
Ignace
I
Lesage
Karl
K
Werbrouck
Patrick
P
D000368:Aged; D000369:Aged, 80 and over; D001530:Belgium; D015653:Cystectomy; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011300:Preoperative Care; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18