Surgery may not be the best for prostate cancer

According to a 15-year study., most patient diagnosed with prostate cancer at a very early stage will choose surgery or radiation treatments with the adverse effects of impotence or incontinence. About 10% choose no treatment at all, this is called watchful waiting or active surveillance or expectant management, normally not recommended by their doctors.  The study, published in New England Journal of Medicine, found that patients with early stage prostate cancer survived the disease whether they opt for surgery or not.

731 men diagnosed with prostate cancer after having high PSA levels were randomly assigned to radical prostatectomy or observation and followed through January 2010. They found that radical prostatectomy did not significantly reduce all-cause or prostate-cancer mortality, as compared with observation. More than 1 in 5 in the surgery group had adverse effects from their operation.

The study suggests that most prostate cancers are not life-threatening, but most patients are given radical prostatectomy and they believe that treatment will eliminate the risk. Many men report pressurised by their doctors and families to seek aggressive treatment. The lead author of the study said the study shows that observation can be a wise and preferred option for most men diagnosed with prostate cancer detected with PSA.

However not all experts agree with the study's conclusion, but all feel that more research is needed to identify which cancer would be harmless and slow-growing. Some said that education and teaching is needed to understand the concept that not all cancers are the same.

Source : Radical Prostatectomy versus Observation for Localized Prostate Cancer. New England Journal of  Medicine 2012; 367:203-213 (July 19, 2012), Abstract only, full text via Athens 90 days after publication.

Provenge therapy for advanced prostate cancer

Prostate cancer is one of the most common malignancy in North American males causing more than 30,000 deaths each year, up to 30% experience recurrence.

Chemotherapy and hormonal therapy are the usual treatment available to these patients, but many patients have progressed to castrate-resistant prostate cancer (CRPC) and chemotherapy has significant side effects.

A new study was published online in the journal Maturitas in May about a novel therapeutic cancer vaccine, Sipuleucel-T, or Provenge, produced by Dendreon Ltd, for the treatment of CRPC after randomized trials showed significant survival advantage compared to controls.

In April 2010, the US FDA approved the vaccine therapy for advanced prostate cancer that has failed to respond to hormone therapy. The therapy involves taking the patient's own immune cells, externally activated against prostate cancer antigen PAP and infuse back into the patient. The patient's own immune system will then create T-cells to attack these cells.


Provenge does not cure prostate cancer but trials show that it extends survival by 4 months or years for some patients. Phase I and Phase II trials show that the vaccine is safe but some patients suffer side effects such as fatigue, headache, back pain, joint pain etc. It is advised that patients should discuss the risks and benefits with their physicians.

Source: "Vaccine therapy with sipuleucel-T (Provenge) for prostate cancer". Maturitas 2011 Aug;69(4):296-303. Epub 2011 May 31

Does statin use reduce prostate cancer recurrence?

Statins is a common treatment to lower cholesterol but a study, published online in June 28 in Cancer, found that men taking statins before their prostate surgery were less likely to show signs of the cancer recurring.

The study reviewed the data of 1319 men who had prostatectomy and took statins when they had their operation and showed that they had a 30% lower risk of PSA recurrence compared to those not taking statins. The greater the dose of statins taken, the less likely the cancer was to reappear.

The researchers said if other studies support their findings, a RCT of statins is warranted. However, critics say that the statin users differed significantly from non-users at presentation, eg they were older and had higher BMI that might affect the association between the statin use and risk for biochemical recurrence, also previous studies had mixed findings.

Another study, published in the Journal of Clinical Oncology, with 691 men underwent radiotherapy, showed a significant association between statin use and decreased biochemical recurrence.

Source:
1). Hamilton RJ, Banez LL, Aronson WJ et al. "Results from the Shared Equal Access Regional Cancer Hospital (SEARCH) Database". Cancer, [Early online publication] June 28 2010

2). "Statin Use and Risk of Prostate Cancer Recurrence in Men Treated With Radiation Therapy". Journal of Clinical Oncology, Vol 28, No 16 (June 1), 2010: pp. 2653-2659
Early Release 10.1200/JCO.2009.27.3003 on April 26 2010

To screen or not to screen for cancer ?

For decades, people always believe cancer screening saves lives, but a study published in JAMA last week expressed concerns about the harm caused on patients who undergo breast and prostate cancer screening.

Dr Laura Esserman and colleagues who carried out the study found that screening often finds harmless or non-life-threatening tumors that could have gone unnoticed, this has led to huge increase in cancer diagnosis and unnecessary and aggressive treatment for patients while the most lethal, fast-growing cancers are often missed.

They reported 40% increase in breast cancer diagnosis but only 10% decline in late stage cancers. The rate of breast cancer overdiagnosis is as high as 1 in 3 for non-invasive cancers. Similarly, diagnosis in prostate cancer rocketed with the PSA test introduced in the 1980s, but most men with high PSA level turn out not to have cancer. Patients diagnosed with these cancers are often aggressivley and overtreated with radiation and surgery leading to long term harm.

The authors pointed out that the dilemma for breast and prostate cancer is that it is difficult to distingush dangerous cancers from harmless ones and the idea that some cancers are not dangerous and might go away on their own is not always accepted.

Although routine screening has identified more early stage cancers, it has not led to a corresponding reduction in mortality rate in breast and prostate cancer. The study concluded that "screening has value but we need to undertsand what it can and cannot do......., less screening is not necessarily a bad thing" and urged clinicians to rethink the use of breast and prostate cancer screening.

The American Cancer Society (ACS), as a result of the findings of this study, has acknowledged that the benefits of early screening has been overstated.

Source: "Rethinking screening for breast cancer and prostate cancer" JAMA. 2009;302(15): 1685-1692. (f/t via Athens)

Minimally invasive surgery vs open surgery for prostate cancer

Despite limited data on outcome, the use of minimally invasive radical prostatectomy (MIRP) has surged as a result of aggressive marketing of the potential benefits over conventional open surgery even at greater costs.

A study published in JAMA reported mixed results. It was a population-based observational cohort study that identified nearly 2000 men who had MIRP and nearly 7000 had traditional surgery.

The researchers found that use of MIRP increased from 9% in 2003 to 43% in 2006-7. White and Asian living in high income areas are more likely to opt for MIRP. They also found that MIRP was associated with shorter hospital stay and fewer blood transfusion or other postoperative complications. However MIRP was associated with incontinence and erectile dysfunction in the long term.

The authors concluded that their findings reflected "a society and health care system enamored with new technology that increased direct and indirect health care costs but had yet to uniformly realize marketed or potential benefits during early adoption."

Source: "Comparative Effectiveness of Minimally Invasive vs Open Radical Prostatectomy". JAMA 2009;302(14):1557-1564. (f/t via Athens)

Does virus cause CFS?

A new study published in Science suggested that the virus XMRV that may play a role in prostate cancer has a strong link with ME, also known as CFS (chronic fatigue syndrome). It was a case control study that looked for the presence of a retrovirus in the white blood cells of people with CFS.

Researchers compared blood samples from 101 patients with CFS with those from 218 people without. They found that the virus was present in the blood of 67% of the CFS patients, compared with 3.7% of the people without CFS. They also found that the virus XMRV could be transmitted to prostate cancer cells in laboratory experiments.

They concluded that XMRV may be a contributing factor in the develoment of CFS and suggested that the virus could be responsible for some of the abnormal immune response in CFS patients. However, larger studies are needed before any conclusions can be drawn.

Critics say this research has identified a link between XMRV virus and CFS but does not prove the virus causes CFS because it is not clear if the infection occured before the disease is developed. Other limitations of the study include small number of patients tested, there is no report on the characteristics of the healthy people whose blood samples were used and contamination of blood samples could not be ruled out completely. However, the findings would be of interests to patients and doctors.

Source:Vincent C. Lombardi 1, Francis W. Ruscetti et al "Detection of an Infectious Retrovirus, XMRV, in Blood Cells of Patients with Chronic Fatigue Syndrome" Published Online October 8, 2009 Science. DOI: 10.1126/science.1179052 (subscription needed)

Prostate cancer wonder pill trial

Multiple news sources reported a small phase 1 trial involving 21 men with aggressive and incurable form of prostate cancer. The participants were given daily dose of a new drug, abiraterone, in 28-day cycles. Researchers found that 12 of the 21 patients had a 50% decline in PSA ( prostate specific antigen) after one month and 6 had a 90% decline. They also found in some patients, tumor shrank, regression of some of the cancers and reduction of the dose of analgaesics required to ease the pain. Researchers said the results indicated the evidence of the safety of abiraterone.

Critics say the results are preliminary and no survival advantage has been proved in this very small trial. A 2nd larger study is already underway and will provide more information about the effectiveness of the drug in treating the disease to a wider group of people.

Source : "Phase I Clinical Trial of a Selective Inhibitor of CYP17, Abiraterone Acetate, Confirms That Castration-Resistant Prostate Cancer Commonly Remains Hormone Driven." Journal of Clinical Oncology 2008; Jul 21 [Epub ahead of print]

Lifestyle changes may slow prostate cancer

Newspapers reported a small pilot study of 31 men with very low risk prostate cancer that looked at the effects of lifestyle changes on the activity of different genes in prostate tissue.

The participants did not want immediate surgery, hormone therapy, or radiotherapy but agreed to change comprehensive lifestyle including good diet and exercise. By the end of the study, they had reduced BMI, blood pressure, waist size and blood lipids. 48 genes were found more active and 453 genes less active after the intervention. Some of them are related to tumour formation.

Researchers concluded that intensive nutritional and lifestyle changes may change gene activity in the prostate and suggest larger studies to confirm their findings.

Source : "Changes in prostate gene expression in men undergoing an intensive nutrition and lifestyle intervention." Proc Natl Acad Sci 2008; [Published online June 16]

Prostate cancer patients often receive mismatched therapy

A study conducted at 4 Massachusetts hospitals using questionnaires to survey more than 400 patients found that prostate cancer patients often receive treatment that is contraindicated by pre-existing conditions such as urinary or bowel dysfunction. It also found mismatched treatments were more common than expected.

The authors raised concerns about poor patient-doctor communication that can lead to poor clinical outcomes.

Source: "Treatment 'Mismatch' In Early Prostate Cancer: Do Treatment Choices Take Patient Quality of Life Into Account?" CANCER; Published Online: November 26, 2007 (DOI: 10.1002/cncr.23138); Print Issue Date: January 1, 2008

Prostate cancer may be missed in obese men

A new study found dcotors may be missing a large number of cancer in obese men because the test for prostate-specific antigen (PSA) is unreliable. It may explain why obese men tend to have more aggressive cancer.

Researchers said doctors must take body weight into account when reading test results for prostate cancer because higher body mass index (BMI) is linked to higher plama volume that can lead to dilution of PSA.

Source: "Obesity-Related Plasma Hemodilution and PSA Concentration Among Men With Prostate Cancer" JAMA. 2007;298(19):2275-2280

Overweight men with prostate cancer have higher risk of dying

A new study that tracked 788 men with prostate cancer also looked at their BMI at the start of the trial and followed up for 8 years. The researchers found that men who are overweight when diagnosed with prostate cancer are twice as likely to die from it. The finding was published in the journal Cancer.


Source : "Obesity and Mortality In Men With Locally Advanced Prostate Cancer: Analysis of RTOG 85-31," Cancer; Published Online: November 12, 2007 (DOI: 10.1002/cncr. 23093); Print Issue Date: December 15, 2007

This is the 3rd post this month about overweight and cancer risk.

Cauliflower and broccoli can cut prostate cancer risk

Almost 32,000 cases of prostate cancer are diagnosed every year in Britian and the risks increase with age.

A new study "Prospective Study of Fruit and Vegetable Intake and Risk of Prostate Cancer" published in the Journal of the National Cancer Institute (JNCI), volume 99, number 15, p.1200-1209, found eating cauliflower and broccoli regularly can almost halve a man's chances of developing prostate cancer. Experts advise the best way to reduce cancer risk is to eat a balanced diet with lots of fruit and vegetables a day. Read the abstract.


The study tracked 29,000 men over a 4-year period, reserachers also monitored their eating habits particularly intake of different vegetables. Read the press release.