Authored date:2006-01-24

Patient History

51 year old patient with prostate cancer. Clinical stage T2 based on digital rectal examination. For accurate staging of the disease, this patient was called for an MRI exam at 3T. With his stage, PSA and Gleason score (PSA =1.0 µg/l Biopsy: Gleason 6/10) the pretest probability of having limited disease (confined to the prostate) is between 52 and 64%, according to the Partin coefficient tables.

Measurement Details

• A prototype of an endorectal coil and interface for 3T (Medrad, Pittsburgh, USA) was used for signal reception. The body coil was used for signal excitation. 
  
• Multislice T2-weighted TSE sequence: 15 axial slices, TR 4490 ms, TE 153 ms, turbo factor 17, FOV 200 x 100 mm, matrix 768 x 384, slice thickness 2.5 mm. Hyperechoes were used to decrease SAR. 
  
• T1-weighted 3D sequence: Axial reconstruction of 32 partitions, TR 8.6 ms, TE 4.0 ms, flip angle 15 degrees, FOV 130 x 65 x 48 mm, matrix 256 x 128 x 32, slice thickness 2.5 mm. 
  
• MAGNETOM Trio, software syngo MR 2004A

Image Findings

Fig. 1  Six out of 15 T2-weighted axial images of the prostate of a 51-year-old patient with prostate cancer. The endorectal coil balloon is visible as a large void below the prostate. The arrows indicate the tumor lesion.

Fig. 2  Six out of 32 T1-weighted images after contrast administration. The thickness of slices and partitions do not coincide, so the slice positions do not exactly match with T2-weighted imaging. The lesion of figure 1 is indicated with the arrows as enhancing tissue.

Fig. 3  Histopathology of the corresponding cut through the resected prostate on which the tumor is indicated with a blue line.

Results and Discussions

On T2-weighted imaging a hypo-intense area is clearly visible in the peripheral zone of the right side of the prostate gland (arrows Fig. 1). This region enhances after administration of contrast agent (Fig. 2). There are no clear signs of extracapsular spread or seminal vesicles invasion of the disease. Based on these findings the diagnosis is stage T2a. 
After staging of the disease, the patient was treated with a prostate and seminal vesicles resection. The resected prostate was cut, stained and investigated at the department of pathology (Fig. 3). The pathological stage confirmed the clinical stage of the disease but found a higher Gleason score: T2a with Gleason grade 3+5. 
The attainable spatial resolution with an endorectal coil at 3T provides excellent opportunities for accurate staging of prostate cancer. In this case the MRI-examination confirms the existence of the cancerous tissue, and provides valuable information on local disease stage.