Imaging & Biopsy Services

Imaging Services - Prostate MRI

Indications for Prostate MRI

• Surgical Planning
  Benefits from endorectal coil and spectroscopy
  • Robotic-Assisted Laparoscopic Prostatectomy (RALP)
  • Intermediate risk of extracapsular extension
• Biopsy planning (MR or ultrasound fusion)
  • Rising PSA/high PSA density & negative biopsy
• Active Surveillance
• Radiotherapy planning
• Follow-up rising PSA ("biochemical failure")
  Benefits from endorectal coil and spectroscopy
  • After prostatectomy or radiotherapy
• Benign disease

Indications for Prostate MRI by Scan Type

• Staging (with endorectal coil, full pelvis, ± spectroscopy)
  • Surgical Planning
• Staging (external array, full pelvis, no spectroscopy)
  • Radiotherapy planning
  • Brachytherapy planning
  • Follow-up of rising PSA after prostatectomy or radiotherapy
• Detection (prostate only, external array only)
  • Rising PSA (or elevated PSA density) & negative biopsy
  • Biopsy planning under MR or US (in development)
• Either Staging or Detection
  • Active Surveillance (formerly "watchful waiting")
• Add lumbar spine to pelvis to stage bones/nodes

Prostate MRI: Biopsy Guidance

• In the face of a rising PSA and negative biopsy, a "second look" is warranted
• MRI can pinpoint the most suspicious area in the prostate
• Biopsy can be done directly with MRI or with ultrasound/MRI image fusion under ultrasound guidance
• Technique is optimized for detection, not staging

Radiation (vs. Biopsy) Planning

• Extracapsular extension and seminal vesicle invasion are important, and often the reason surgery is deferred
• Delineation of adjacent structures
  • Urethra and bladder
  • Rectum
  • Pelvic floor muscles and neurovascular bundles
• Evaluates pelvic lymph nodes and bones
• Localization of cancer in the prostate is less important, but can guide a "boost"
• The endorectal coil distorts anatomy, complicating planning, and is omitted

Prostate MRI: Active Surveillance

• In patients with low volume, low grade disease, MRI provides two advantages
  • Screen for missed areas suspicious for high-grade cancer
  • Baseline imaging for follow-up, to look for subtle changes

Follow-Up Rising PSA: Biochemical Failure

• A rising PSA level after prostatectomy suggests recurrence of cancer
• MRI has been shown to be sensitive to detect recurrent cancer
  • Surgical bed
  • Bones
  • Lymph nodes
• MRI can also detect recurrence in the radiation therapy field