Long-term Oncological Outcomes of Partial Gland Cryoablation of Localized Prostate Cancer with Median Follow-up of 7 Years: A Single-institution Experience.

Background and objective: Traditional radical approaches to treat clinically localized prostate cancer (PCa) have largely been effective oncologically, but associated with complications and decline in functional outcomes, arguably making them unsuitable in all cases for treatment. This necessitates an alternative option, focal therapy (FT), which has good oncological control while reducing treatment-related functional detriments. Although midterm oncological and functional outcomes of FT have been demonstrated, the long-term outcomes were lacking. We sought to report the long-term oncological outcomes of partial gland cryoablation (PGA) for nonmetastatic PCa treatment.

Methods: This is an institutional review board-approved retrospective analysis of a prospectively maintained database of patients who have undergone PGA of the prostate at Duke between 2005 and 2020, with a minimum follow-up of 3 yr. The primary outcome was to determine the 5- and 10-yr failure-free survival (FFS), defined as a requirement of radical, whole-gland therapy for recurrence and/or systemic therapy, or metastases/death (cancer specific). The secondary outcomes include cancer-specific (CSS), overall (OS), and metastasis-free (MFS) survival. We also evaluated the functional outcomes, including the continence rate defined as strictly "pad free" and preserved erectile function (patient reported, with/without pharmacological intervention, defined as an erection sufficient for sexual intercourse of those patients who were initially potent, International Index of Erectile Function 5 ≥17) at 12 mo.

Key findings and limitations: A total of 70 patients with complete data met the study inclusion criteria. The median follow-up was 86 mo (interquartile range [IQR], 46-113). The median age was 75 yr (IQR, 69-80) and the median preoperative prostate-specific antigen was 6.5 ng/ml (IQR, 4.7-9.34). Of 70 patients, 43 (61%) and six (9%) had D'Amico intermediate- and high-risk disease, respectively. FFS was 92% (95% confidence interval [CI]: 81-96%) at 5 yr and 70% (95% CI: 52-82%) at 10 yr. The MFS, CSS, and OS at 10 yr were 96% (95% CI: 86-99%), 98% (95% CI: 89-99%), and 89% (95% CI 75-95%), respectively. There was a significant improvement in the median International Prostate Symptom Score from 6.5 (IQR, 3-12) at baseline to 4 (IQR, 2-9) at 12 mo (p = 0.03). About 73% (32/44) of patients who were initially potent were able to maintain erections sufficient for sexual intercourse, and 97% (68/70) of patients are continent requiring no pad usage at 12-mo follow-up.

Conclusions and clinical implications: Primary focal cryoablation for PCa has good long-term oncological control in men with localized PCa. FT may be a better option for men who desire to preserve good functional outcomes and thus quality of life.