Minimally invasive prostate cancer techniques take center stage at AUA

May 15, 2010

Studies on minimally invasive surgery will again have a prominent place among research being presented on localized prostate cancer at the AUA annual meeting.

Key Points

In the area of minimally invasive surgery, several groups will be reporting on outcomes of high-intensity focused ultrasound (HIFU). Overall, the results suggest that this modality is effective for treating low-grade, low-volume localized prostate cancer. However, without data from randomized, prospective clinical trials, Dr. Williams said he remains skeptical about the curative role of HIFU in higher grade/volume disease.

"In my view, this minimally invasive therapy probably works best in patients with minimal disease, and in those men, it may be no different than active surveillance. I question whether a treatment that does not guarantee cancer eradication contributes any clinically important difference," he told Urology Times.

Studies on robot-assisted laparoscopic radical prostatectomy (RALRP) will continue to take center stage at the AUA meeting. The latest results are reaffirming that RALRP offers improved outcomes in terms of reducing blood loss and rates of local complications when performed in the hands of experienced surgeons relative to those who have done fewer procedures. However, considering length of hospital stay data, there may be no benefit for RALRP compared with open radical prostatectomy performed by skilled surgeons, said Dr. Williams.

"Nevertheless, there is increasing market demand for minimally invasive procedures as patients are convinced of their superiority, and so urologic surgeons will need to become skilled in the robotic technique," he said. "However, we still have to figure out ways to make it better."

Neoadjuvant therapy research continues

Research focusing on identifying effective neoadjuvant therapies for treatment of men with localized prostate cancer is continuing. Data being reported at the AUA meeting on docetaxel (Taxotere) will show it results in a higher risk of complications without benefits for improving disease stage or grade.

"While docetaxel does not appear to be a major step forward, the need remains to identify effective methods to downgrade tumors prior to more definitive treatment, and there are some investigational agents showing promise," Dr. Williams said.

Urologists may also anticipate forthcoming advances in imaging techniques for staging to identify tumors in the prostate and sites of disease progression. Data being presented at the meeting indicate the superiority of magnetic resonance imaging to computed tomography scanning and other imaging studies for detecting positive lymph nodes and local extension, although the specificity of MRI is still not absolute. In the area of positron emission tomography scanning, investigators will report that use of 11C-acetate as the isotope has promise of better sensitivity than the previously studied fludeoxyglucose.

In the area of active surveillance, researchers at the AUA meeting are reporting survey data documenting that patients who select this option are comfortable and satisfied with it.

"Further study is needed on this topic, but it appears that with shared decision making, where patients understand the findings about efficacy and potential risks, they can opt for this conservative approach to management without significant anxiety about cancer progression," Dr. Williams said.

Reports on smoking, statins, recurrence

The AUA program also includes two interesting reports about associations between cigarette smoking and statins and the risk of biochemical recurrence following treatment for localized prostate cancer.

"Benefits found in nonsmokers compared with current smokers and in men on statins relative to their untreated counterparts may be explained by differences in body mass index, heart disease, or other factors. However, there may also be a direct biologic effect of smoking and statin use that warrants further study," said Dr. Williams.

Looking ahead, urologists may expect to hear more about immunotherapy with therapeutic vaccines for adjuvant/neoadjuvant use in men with minimal disease. While disappointing results were obtained in some previous studies, other vaccine approaches to stimulate a host antibody and/or T-cell response are showing promise and may represent the future in management of localized/recurrent prostate cancer.

Research continues investigating circulating tumor cells that can be differentiated as progression markers, and identification of those having prognostic significance may be expected in the not-too-distant future. This information will have important relevance to refining approaches to prostate cancer screening and active surveillance, noted Dr. Williams.

As controversy on routine screening for prostate cancer continues after the publication of results from U.S. and European randomized clinical trials, Dr. Williams said he disagrees with those who have interpreted the findings as conclusive evidence against performing prostate cancer screening.

"The final answer on this issue is still to be decided," he said. "However, the importance of selective screening for at-risk men, including those with a primary family history of prostate cancer, African-Americans, and those with any other high-risk feature, continues to be supported by the AUA and recognized by most urologists, as does shared decision making with patients who are fully informed about the potential benefits and limitations of screening."