“Male Lumpectomy”: Focal Therapy for Prostate Cancer Using Cryoablation

Abstract

The introduction of breast-sparing surgery (ie, "lumpectomy") revolutionized the management of breast cancer. The use of lumpectomy showed that quality of life could be optimized without compromising treatment efficacy. Complications of prostate cancer treatment, including impotence and incontinence, adversely alter the male self-image similarly to the way the loss of a breast does for a woman. Traditional thinking holds that prostate cancer is multifocal and therefore is not amenable to focal treatment. However, histopathologic findings from published data have indicated that up to 25% of prostate cancers are solitary and unilateral. Furthermore, the significance of minute secondary cancers might be minimal. These observations raise the question of whether certain patients can be identified and treated with a limited "lumpectomy." In this study, focal cryoablation has been used to ablate the area of known cancer as determined by staging biopsies. The serum prostate-specific antigen (PSA) concentration was obtained every 3 months for 2 years and every 6 months thereafter. American Society for Therapeutic Radiology Oncology (ASTRO) criteria for PSA recurrence were used. A total of 55 patients with > or = 1 year of follow-up had undergone focal cryoablation. Follow-up ranged from 1 to 10 years (mean, 3.6 years). At the original transrectal ultrasound biopsy, the mean and median numbers of cores taken were 9.9 and 10 (SD, +/- 3.5), respectively. Mean and median numbers of positive cores were 1.8 and 1 (SD, +/- 1.3), respectively. Of the 55 study patients, 52 (95%) had stable PSA levels with no evidence of cancer despite a medium to high risk for recurrence in 29 patients. All biopsy findings were negative among the 26 patients with a stable PSA level who had undergone routine biopsy at 1 year. No local recurrence was noted in treated areas. Potency was maintained in 44 (86%) of 51 patients. Of the 54 patients without previous prostate surgery or radiotherapy, all were continent. These preliminary results indicate that "male lumpectomy"--in which the prostate tumor region itself is destroyed--preserves potency in most patients and limits other complications (particularly incontinence) without compromising cancer control. Additional studies and long-term follow-up are needed to confirm that this treatment approach could have a profound effect on prostate cancer management.