V4-09: MRI Guided Salvage Cryoablation of Recurrent Prostate Cancer
Prostate cancer is the most common non-cutaneous malignancy in men in the United States, and cancer recurrence after definitive therapy can be as high as 30%. Recurrent cancer presents many challenges. Finding the site of recurrence is difficult, and once found, the optimal treatment modality must be determined. We present a patient with MRI detected, biopsy proven local recurrence treated with MRI guided salvage cryoablation.
A 57 year old man underwent open radical retropubic prostatectomy for a Gleason 3+4 T3a N0 R0 prostate cancer. At his 6 year follow-up, his PSA rose to 1.3 ng/dL and he underwent salvage intensity modulated radiation therapy. 2 years later, his PSA was 1.9 ng/dl and MRI and TRUS biopsy demonstrated a 1.1 by 2 cm mass in the left vesicourethral anastomosis. CT imaging and bone scan demonstrated no evidence of metastatic disease.
After extensive discussion of therapeutic options, the patient elected to proceed with MRI guided salvage cryoablation. Initial treatment was with four cryoprobes spaced 1 cm apart. Two freezing cycles were performed with 7 minutes of freezing time. Post-ablation, his PSA nadired at 0.22 ng/mL, and repeat MRI demonstrated a residual 7 mm by 7 mm mass in the left vesicourethral anastomosis. Repeat TRUS biopsy demonstrated a Gleason 4+4 prostate cancer. The patient underwent a second ablation separating the cryoprobes by 5 mm and using 3 cycles of freezing. Since then, his PSA has remained undetectable with no evidence of disease for 5 years.
MRI allows precise placement of the cryoprobes. In addition, active imaging provides ice ball monitoring that improves the safety and precision of cryotherapy. In the appropriate patient, this technique may provide durable cancer-free survival.