Optimal Use of Bone-Targeted Therapy for mCRPC

November 2014

• A 55-year old gentleman presented with nocturia and PSA level of 4.5 ng/mL
• PMH: Insignificant
• DRE revealed an abnormal area of hardness
• Biopsy showed adenocarcinoma of the prostate gland with a Gleason score 6 [3+3], clinical tumor stage T1c                                                                                                                                                                  
• The patient remained on active surveillance

November 2015

• When he returned after 1 year:
  • PSA, 10 ng/mL
  • Repeat biopsy showed Gleason 7 [4+3] with 8 of 12 cores positive
  • CT scan was negative for metastases
  • He remained asymptomatic
• He was started on a 3-month depot injection of goserelin

February 2016

• PSA, 34 ng/mL
• CT scan was negative for metastases
• He was started on abiraterone and prednisone
  • PSA declined to 15 ng/mL and remained stable
  • After 4 months, he developed cardiac arrhythmia attributed to prednisone; he was switched to enzalutamide
  • PSA remained stable

August 2016

• 3 months following therapy switch, the patient complained of severe fatigue
  • CT scan showed enlarged lumbar spine and pelvic bone metastases
  • ¹⁸F-FDG PET showed increased FDG uptake in several areas of the lumbar spine and pelvis
  • PSA, 45 ng/mL
  • ALP, 225 U/I
• Radium-223 therapy was initiated and enzalutamide was continued
• After 4 cycles of radium-223:
  • Fatigue decreased significantly
  • PSA, 25 ng/mL
  • ALP, WNL
  • CT showed no new bone metastases