Apparent diffusion coefficient values and dynamic contrast enhancement patterns in differentiating seminomas from nonseminomatous testicular neoplasms.
BACKGROUND
The aim of this study is to investigate the role of apparent diffusion coefficient (ADC) values and dynamic contrast enhancement (DCE) patterns in differentiating seminomas from nonseminomatous germ cell tumors (NSGCTs).


METHODS
The MRI examinations of the scrotum of 26 men with histologically proven testicular GCTs were reviewed. DWI was performed in all patients, using a single shot, multi-slice spin-echo planar diffusion pulse sequence and b-values of 0 and 900 s/mm(2). Subtraction DCE-MRI was performed in 20 cases using a 3D fast-field echo sequence after gadolinium administration. Time-signal intensity curves were created and semi-quantitative parameters (peak enhancement, time to peak, wash-in and wash-out rate) were calculated. The Student's t-test was used to compare the mean values of ADC, peak enhancement, time to peak, wash-in and wash-out rate between seminomas and NSGCTs. ROC analysis was also performed.


RESULTS
Histopathology disclosed the presence of 15 seminomas and 11 NSGCTs. The mean ± s.d. of ADC values (×10(-3)mm(2)/s) of seminomas (0.59 ± 0.009) were significantly lower than those of NSGCTs (0.90 ± 0.33) (P=0.01). The optimal ADC cut-off value was 0.68 × 10(-3)mm(2)/s. No differences between the two groups were observed for peak enhancement (P=0.18), time to peak (P=0.63) wash-in rate (P=0.32) and wash-out rate (P=0.18).


CONCLUSIONS
ADC values may be used to preoperatively differentiate seminomas from NSGCTs.
Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: a_tsili@yahoo.gr.
Athina C
AC
Tsili
Department of Urology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: anasylakos@yahoo.gr.
Anastasios
A
Sylakos
Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: alexdorkou@yahoo.com.
Alexandra
A
Ntorkou
Department of Urology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: s.sotiris@yahoo.gr.
Sotirios
S
Stavrou
Department of Medical Physics, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: astrakas@uoi.gr.
Loukas G
LG
Astrakas
Department of Urology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: akrosnin@hotmail.com.
Nikolaos
N
Sofikitis
Department of Radiology, Medical School, University of Ioannina, 45110 Ioannina, Greece. Electronic address: margyrop@cc.uoi.gr.
Maria I
MI
Argyropoulou
D000328:Adult; D002278:Carcinoma in Situ / Q000473:pathology; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009373:Neoplasms, Germ Cell and Embryonal / Q000473:pathology*; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012611:Scrotum / Q000473:pathology*; D018239:Seminoma / Q000473:pathology*; D012680:Sensitivity and Specificity; D013736:Testicular Neoplasms / Q000473:pathology*
D003287:Contrast Media
Apparent diffusion coefficient; Differential diagnosis; Diffusion-weighted imaging; Dynamic MRI; Testicular tumors