Obesity May Affect Prostate Cancer Test

Obese men may have prostate cancer despite relatively low values on the prostate cancer screening test, a new study suggests. The PSA test detects PSA – prostate-specific antigen – in the blood. Only prostate cells give off PSA, and levels of the hormone can rise as prostate tumors grow.

Earlier studies showed that obese men have slightly lower PSA concentrations than lean men do. It’s not clear why this is so. New findings from Duke University researcher Stephen J. Freedland, MD, and colleagues now suggest an answer.

“Being a big guy, you have enormous blood volume, so PSA is diluted,” Freedland said. “Obese men having these lower PSA values due to the dilution factor means we are going to miss some of them early on.”

Other recent studies have shown that obese men have a higher risk of dying from prostate cancer than other men, and a delay in cancer detection may be part of the reason.
Results of the study were published in the November 21 issue of the Journal of the American Medical Association.

Study links being overweight to prostate cancer survival rate

The New York Times (11/13, Bakalar) reports on a new study which suggests that “overweight men with advanced prostate cancer” do not live as long as patients with normal body mass. For the study, which was published online Monday, and is “scheduled to appear in the Dec. 15 issue of the journal Cancer, lead author Matthew R. Smith, M.D., an oncologist at Massachusetts General Hospital in Boston, and colleagues, looked at 788 men” receiving “different types of therapies for prostate cancer. More than 50 percent of them were either overweight or obese.”

Extra fat raised the risk of dying from the disease by 52 percent, and obesity increased it to 64 percent, after researchers adjusted for other medical reasons. According to Dr. Smith, the reasons for this are not fully understood. However, he speculated, “It may be that prostate cancer treatments are less effective in men who have higher weights, or that other illnesses these men may have — such as diabetes — play a role in the increased risk of prostate cancer death.”

Robotic Surgery May Improve Survival Rate For Prostate Cancer Patients

Performing less invasive laparoscopic surgery using robotic technology may improve survival rates for prostate cancer patients, according to a study by urologic oncologists at Thomas Jefferson University Hospital’s multidisciplinary Genitourinary (GU) cancer center.

In a study presented May 21, 2007 at the annual American Urological Society meeting in Anaheim, Calif., the Jefferson urologists found that performing a laparoscopic radical prostatectomy (LRP) with robot technology can reduce positive surgical margins. Positive surgical margins refers to when cancer, seen under a microscope, goes to the edge of a specimen, meaning that cancerous cells likely remain in the patient. LRP is the surgical removal of the entire prostate gland and surrounding tissue including the seminal vessels through several tiny incisions. “We demonstrated a significant improvement (lowering) in the positive surgical margin rate with the addition of robotics to an established LRP,“ said Costas Lallas, M.D., assistant professor of Urology, Jefferson Medical College of Thomas Jefferson University, one of the investigators.

Laparoscopic surgery has proven to offer potential advantages to patients including less trauma through smaller incisions, faster recovery and less overall blood loss during surgery, allowing most patients to leave the hospital in one day. The robotic system further refines laparoscopic prostatectomy by allowing a surgeon’s hand movements to be scaled, filtered and translated into precise movements of micro-instruments within the operative field. The magnified, three-dimensional view the surgeon experiences enables him to perform precise surgery in complex procedures, such as radical prostatectomy, through small surgical incisions.

MBUA have been performing robot-assisted laparoscopic radical prostatectomy since 2003, and are the only urologists in the Monterey Bay area who perform robotic prostatectomy using the da Vinci Surgical System. Our experience is the same as reported in this study and others; patients recover much faster after robotic prostatectomy than after open surgery, and the cancer cure rate, and recovery of normal urinary and sexual function are superior compared to open prostate cancer surgery.

Penis Size Perceptions: The Grass is always Taller…

The UPI reported that “although men often have a better body image, a better genital image and more sexual confidence if they have a large penis, women don’t necessarily feel that bigger is better,“ according to a review in the British Journal Urology International. The results of “12 studies that measured the penises of 11,531 men found that on average, erect penises ranged from 5.5 to 6.2 inches in length and 4.7 to 5.1 inches in girth. A survey of over 50,000 heterosexual men and women found that 66 percent of men said their penis was average-sized, 22 percent said large and 12 percent said small.“ And, while “85 percent of women were satisfied with their partner’s penile size, only 55 percent of men were satisfied with their penile size.“

The truth is that we all have what we are born with, and there is no way to create more. Men should not purchase supplements that purport to increase penis size because they don’t work, and there are no surgeries that can give men more than they have. Fortunately, the vast majority of women are satisfied with the size of their partner’s penis, which shows that it matters more how men make love than what their penis looks like.

MBUA opens new Santa Cruz Office

Monterey Bay Urology Associates moved into our new Santa Cruz office on November 5th, 2007. The office is located at 1575 Soquel Drive, right next to Dominican Hospital. Our phone number is unchanged, 831-476-2626. We have a new medical assistant, Maribel Deloera, who will be checking in patients and assisting the physicians. Dr. Benjamin and Dr. Rosen will be seeing patients in Santa Cruz and Watsonville, Dr. Knorr will be seeing patients in Watsonville only. We will be sharing the office with Robert Allen, M.D., a local general surgeon. You can call us 5 days a week, and the office staff will be happy to assist you and schedule your appointment.

Outcomes comparable for cryosurgery and radiation therapy in prostate cancer

After nearly 7 years of follow-up, cryoablation appears to be as effective as external beam radiation therapy (EBRT) in the treatment of localized prostate cancer, according to the results of a prospective, randomized trial by researchers at the University of Calgary, Alberta, Canada.
No evidence of disease progression—defined as no biochemical evidence of progression, no radiologic evidence of metastasis, and no need for secondary treatment—is the primary efficacy endpoint for the study.

With a median duration of follow-up of 82 months, the rates of no evidence of disease progression in the cryoablation and EBRT groups were 75.7% versus 73.9% at 36 months, 72.7% versus 61.6% at 48 months, and 70.4% versus 58.3% at 60 months. The differences between groups are not statistically significant; however, there is a trend favoring cryoablation over EBRT at 48 months and 60 months, and a statistically significant difference favoring cryoablation over EBRT in the secondary endpoint of persistence of local control at 36 months (negative 10-core transrectal ultrasound-guided biopsy rates, 93.5% vs. 73.3%).

“Controversy continues over what constitutes optimal treatment for localized prostate cancer as there remains a conspicuous lack of randomized trials directly comparing different modalities,” said lead author Bryan J. Donnelly, MD. “Our experience with accrual underlines that such head-to-head studies are difficult, but can be done, and the results from this study to date suggest cryoablation and EBRT can be considered similarly effective.”

New Blood Test for Prostate Cancer Showing Promise

A new blood test, called EPCA-2, is showing potential as a screening blood test for prostate cancer. It is hoped that the EPCA-2 test will be more accurate than the current test, PSA, and detect more cancers with fewer negative biopsies. While screening for prostate-specific antigen (PSA) has been the standard of care for more than 2 decades, it is not specific for prostate cancer, and raised concentrations have been linked to other prostate conditions such as benign prostatic hyperplasia and prostatitis. Several groups have been working to identify new biomarkers for prostate cancer, and this latest effort, published in the April issue of Urology, shows that EPCA-2 has potential as a new serum-based test.

Due to elevated PSA levels, an estimated 1.6 million men undergo prostatic biopsies in the United States every year. Approximately 60% of these patients have negative results, reports a news release about the study. Conversely, about 15% of men with prostate cancer go undetected because their PSA levels are below the cutoff level. The most recent study showed negative results in normal men 92% of the time, meaning that few men without cancer would have an elevated test and undergo biopsy. The study also found that 94% of men with cancer had an elevated test and would be biopsied, and few men with cancer would be missed by the test.

EPCA-2 is the second prostate-cancer marker identified by the same researchers that has outperformed PSA. Last year, the team identified a tissue-based test, EPCA-1, that also proved effective in flagging prostate cancer. The only similarity between these markers is that they were discovered using the same approach. The efficacy of EPCA-1 as a test of biopsy samples is currently being studied.

“A blood test based on EPCA-2 may greatly improve our ability to accurately detect prostate cancer early, minimize the number of false positives, and lower the number of unnecessary biopsies,“ senior author Robert Getzenberg, PhD, from the Brady Urological Institute at Johns Hopkins Hospital, in Baltimore, Maryland, told reporters. “In addition, this is the first time we have a test that effectively distinguishes between men with cancer confined to the prostate and those whose disease has spread outside the gland.“

The investigators report, “The results of our study have shown that EPCA-2 is a novel biomarker associated with prostate cancer that has high sensitivity and specificity and accurately differentiates between men with organ-confined and non–organ-confined disease.“ Dr. Getzenberg says larger clinical trials for EPCA-2 are planned that could make this test available in about 18 months.