Treatment options for patients with prostate cancer who develop metastatic disease after hormonal therapy.

The patient is a 66-year-old man in good cardiovascular health. He has a family history of prostate cancer. He presents with fatigue and minor discomfort in his lower back. He had not undergone previous prostate-specific antigen (PSA) testing. His first PSA test shows an elevated level of 7 ng/mL. Imaging reveals 3 bone metastases: 2 in the pelvis and 1 in the right posterior rib (Figure 1A). He has no visceral disease. His Gleason score is 4+4. The patient is diagnosed with metastatic hormone-sensitive prostate cancer (mHSPC), and he begins treatment with abiraterone acetate (Zytiga, Janssen) plus prednisone. A dual X-ray absorptiometry (DEXA) scan reveals an index T-score of –1.5 in his femurs. Based on the moderate risk for fracture, he begins treatment with androgen deprivation therapy (ADT) plus zoledronic acid. Three months later, the patient’s PSA is undetectable and his pain has resolved. At 18 months, he presents with increased discomfort in his lower back and increased fatigue. His PSA level has risen from undetectable to 3 ng/ mL in the past 3 months. Repeat imaging reveals a new lesion in the lower spine. Minor lymph node involvement is also detected. Based on the increase in PSA and the new lesion, the patient is diagnosed with metastatic castration-resistant prostate cancer (mCRPC). Treatment with abiraterone acetate is discontinued. The patient begins treatment with radium-223 (Xofigo, Bayer) and receives 6 cycles. His PSA level rises to 10 ng/mL. He has no reported discomfort in the lower back. A repeat bone scan shows stable disease. The patient begins treatment with enzalutamide (Xtandi, Astellas/Pfizer). After an initial PSA decline on enzalutamide, his PSA reaches a nadir of 3.5 ng/mL after 3 months of treatment. At 33 months (6 months on enzalutamide), the patient presents with moderate fatigue. His PSA level is now 20 ng/mL. Imaging reveals osseous metastases that increased in size and number, but no metastases beyond the bone (Figure 1B). His hemoglobin score is 11.5 g/dL, and his alkaline phosphatase level is 150 U/L. The remainder of his blood counts are within normal limits. Treatment with enzalutamide is discontinued. The patient receives 6 cycles of chemotherapy with docetaxel and prednisone. He remains clinically stable. Chemotherapy leads to side effects such as fatigue, anemia, and grade 1 peripheral neuropathy. Treatment Options for Patients With Prostate Cancer Who Develop Metastatic Disease After Hormonal Therapy