‘Male lumpectomy’ works well in prostate cancer

The ‘very aggressive’ focal cryoablation technique succeeds without affecting potency or continence. Focal cryoablation results in better local control of prostate cancer than other standard treatments. By destroying only the cancerous portion of the prostate, a "male lumpectomy" results in high potency rates and limits other complications, particularly incontinence, without compromising cancer control. "This is a very aggressive treatment, even though it is focal. The rationale for male lumpectomy in prostate cancer stems from the tremendous impact that lumpectomies have had on breast cancer treatment. Traditional thinking held that prostate cancer was multifocal and therefore not a amenable to a focal treatment approach. But pathology data indicate that up to 25% of prostate cancers are unifocal, and that 80% of cases would be appropriate for lumpectomy.

It seems to be a rational middle ground between watchful waiting and whole gland treatments, which are associated with significant morbidity. Careful monitoring and the ability to re-treat also provide a safety net for the procedure. Doctor performed focal cryoablation in 96 patients with prostate cancer, and has obtained data on 55 patients with at least 1 year of follow-up (range 1-10 years). Prostate-specific antigen (PSA) tests were obtained every 3 months for 2 years, and every 6 months thereafter. Routine biopsies were obtained in the first 26 patients, and all were negative. At an average of 3.5 years of follow-up, 52 (94.5%) of the 55 patients had stable PSA levels, and were disease-free according to American Society for Therapeutic Radiology and Oncology criteria. Although four patients had to be re-treated after cancer was found in another area of the prostate, there have been recurrences in treated areas. The results are particularly noteworthy as 29 of the 55 patients were at medium to high risk for recurrence. Before the procedure, 51 men were potent. After the lumpectomy, 44 (86%) of those 51 men were potent to their satisfaction. All patients were immediately continent.

Candidates for lumpectomy are patients with a unifocal tumor or one large index tumor and another small tumor less than 5 mm in diameter. The procedure would not be recommended for patients with diffuse disease. When asked by the audience if there is any volume of tumor that he would not treat, the critical point is that the disease should be focal, but added that 1 in 10 of the treatments now are for extracapsular disease in which the whole side of the gland is involved. The key to successful prostate cryoablation is accurate identification of cancer stage, grade, and location. Imaging or standard transrectal ultrasound biopsy results are not sensitive enough, according to a doctor, who has switched to a new 3D biopsy mapping technique in which he obtains a transperineal biopsy every 5 mm and tests every specimen based on its location. Better identification of the disease makes it possible to use focal cryoablation to reliably eradicate the disease and avoid destroying healthy surrounding tissue, which can occur with conventional cryoablation or radiation.

Imaging is not telling us the full extent of the disease — it’s not even close. So that’s why we’ve come down to the mapping biopsy.