Role of18F-Choline PET/CT in guiding biopsy in patients with risen PSA levels and previous negative biopsy for prostate cancer.
OBJECTIVE
To study18F-Choline PET/CT in the diagnosis and biopsy guide of prostate cancer (pCa) in patients with persistently high prostate-specific antigen (PSA) and previous negative prostate biopsy. To compare the clinical risk factors and metabolic variables as predictors of malignancy.


METHODS
Patients with persistently elevated PSA in serum (total PSA >4ng/mL) and at least a previous negative or inconclusive biopsy were consecutively referred for a whole body18F-Choline PET/CT. Patient age, PSA level, PSA doubling time (PSAdt) and PSA velocity (PSAvel) were obtained. PET images were visually (positive or negative) and semiquantitatively (SUVmax) reviewed.18F-Choline uptake prostate patterns were defined as focal, multifocal, homogeneous or heterogeneous. Histology on biopsy using transrectal ultrasound-guided approach was the gold standard. Sensitivity (Se), specificity (Sp) and accuracy (Ac) of PET/CT for diagnosis of pCa were evaluated using per-patient and per-prostate lobe analysis. Receiver-operating-characteristic (ROC) curve analysis was used to assess the value of SUVmax to diagnose pCa. Correlation between PET/CT and biopsy results per-prostate lobe was assessed using the Chi-square test. Univariate and multivariate logistic regression analysis were applied to compare clinical risk factors and metabolic variables as predictors of malignancy.


RESULTS
Thirty-six out of 43 patients with histologic confirmation were included. In 11 (30.5%) patients, pCa was diagnosed (Gleason score from 4 to 9). The mean values of patient age, PSA level, PSAdt and PSAvel were: 65.5 years, 15.6ng/ml, 28.1 months and 8.5ng/mL per year, respectively. Thirty-three patients had a positive PET/CT; 18 had a focal pattern, 7 multifocal, 4 homogeneous and 4 heterogeneous. Se, Sp and Ac of PET/CT were of 100%, 12% and 38% in the patient based analysis, and 87%, 29% and 14% in the prostate lobe based analysis, respectively. The ROC curve analysis of SUVmax showed an AUC of 0.568 (p=0.52). On a lobe analysis, poor agreement was observed between PET/CT findings and biopsy results (p=0.097). In the univariate/multivariate analysis, none of clinical and metabolic variables were statistically significant as predictor of pCa.


CONCLUSIONS
Choline PET/CT is a suitable procedure for the detection of pCa in highly selected patients, however, a high rate of false positive should be expected.
Nuclear Medicine Department, Hospital Universitario de Ciudad Real, Ciudad Real, Spain. Electronic address: gjimenez91@yahoo.com.
G A
GA
Jiménez Londoño
Nuclear Medicine Department, Hospital Universitario de Ciudad Real, Ciudad Real, Spain.
A M
AM
García Vicente
Mathematic Department, University of Castilla La Mancha, Ciudad Real, Spain.
M
M
Amo-Salas
Urology Department, Hospital Virgen de Altagracia, Manzanares, Ciudad Real, Spain.
F
F
Fúnez Mayorga
Urology Department, Hospital Virgen de la Salud, Toledo, Spain.
M A
MA
López Guerrero
Nuclear Medicine Department, Hospital Universitario de Ciudad Real, Ciudad Real, Spain.
M P
MP
Talavera Rubio
Urology Department, Hospital Nuestra Señora del Prado, Talavera de la Reina, Toledo, Spain.
P
P
Gutierrez Martin
Nuclear Medicine Department, Hospital Universitario de Ciudad Real, Ciudad Real, Spain.
B
B
González García
Urology Department, Hospital Nuestra Señora del Prado, Talavera de la Reina, Toledo, Spain.
J A
JA
de la Torre Pérez
Nuclear Medicine Department, Hospital Universitario de Ciudad Real, Ciudad Real, Spain.
Á M
ÁM
Soriano Castrejón
D000230:Adenocarcinoma / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology; D000368:Aged; D001707:Biopsy, Needle / Q000379:methods*; D002794:Choline; D005189:False Positive Reactions; D005462:Fluorine Radioisotopes; D006801:Humans; D061705:Image-Guided Biopsy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology; D011472:Prostatitis / Q000000981:diagnostic imaging; D012680:Sensitivity and Specificity; D051598:Whole Body Imaging
D005462:Fluorine Radioisotopes; D017430:Prostate-Specific Antigen; D002794:Choline
(18)F-Choline; (18)F-Colina; Biopsia dirigida; Cáncer de próstata; Prostate cancer; Targeted biopsy