The new tactics can help doctors decide whether to refer patients with high levels of prostate-specific antigen (PSA) to prevent prostate cancer.
"There is no real strategy for consulting general practitioners, how to refer patients to a specialist for a biopsy," - Jan Verbeek said, MD, of the Erasmus Medical Center in Rotterdam, the Netherlands.
"Some doctors will refer patients to a specialist if their PSA level is high, but others believe that the level of PSA can be high for some other reason, and does not depend on oncology," - he told Medscape Medical News. "We have developed a forecasting tool to help doctors decide whether the patient really needs to worry about prostate cancer or not."
For patients who can benefit from treatment, you should include those whose life expectancy is limited and there is no increased risk of having a potentially aggressive prostate cancer, he explained Verbik during a poster session here at the European Association of Urology Congress in 2018.
Variables, which is based forecasting tool readily available to general practitioners: PSA, percent free PSA, patient age, life expectancy, and comorbidity.
Verbik and his colleagues analyzed data on 19,553 men aged 55 to 74 years who were initially involved in the European Randomized Study of Screening for Prostate Cancer (ERSPC) from 1993 to 1999.
To get results, the researchers used modern tables of life expectancy and the two prognostic factors: the rate of comorbidity index Charlson health and self-esteem.
survival curves for men with clinically significant prostate cancer who were not treated were obtained from the surveillance program, Epidemiology, and End Results (SEER), stratified by age and comorbidities.
They evaluated the effect of treatment for prostate cancer, using the results of the intervention against prostate cancer versus observation (PIVOT).
Models predict both prostate cancer and life expectancy were evaluated using the area located at the operating characteristic curve.
The first man 65 years old, has a record index Charlson comorbidity 0 and in good health. "We expect a 10% chance of prostate cancer on biopsy," - Verbik said.
On the basis of data from the ERSPC, SEER database and the PIVOT study data expected duration of the patient's life is 15 years, if there is no prostate cancer. But if you find oncology, and will be treated, "life expectancy is 17 years. He lives 2 more years with treatment, "- explained Verbik. "So, the patient should be referred for a biopsy."
The second man - 75 years old, has a record rate of comorbidity of Charlson 2 and poor health. It is expected that a life expectancy of only 5 years.
The likelihood that prostate cancer is detected by biopsy, higher - 17% - because he is older. 10-year risk of death is almost identical, if treated for cancer or not (81% vs. 82%).
Thus, the death rate from treatment for 10 years is only 1% in this older, sick person.
The researchers hope that the proposed instrument, which, as they say, should be available soon, will help doctors to primary health-care sort of patients for timely referral to a biopsy, thereby reducing unnecessary testing and inaccurate diagnosis.
Based on how to make treatment decisions for individual patients is difficult because individual patients deviate from the statistical forecasts, said Hendrik Van Poppel, MD, of the University of Leuven in Belgium.
The average life expectancy in Belgium is 81 years for men and 82 years for women. "If I have a patient who 75 years, I can say that he will survive another 7 years, so do not post it on a biopsy," - he told Medscape Medical News.
But even though the statistics show that the patient will die at 81 years old, he can live to 92. "Then the disease progresses, and he was too old to be actively treated. This is a problem with all the statistics that we have ", - Van Poppel said.
MRI suggested Van Poppel, may help doctors avoid unnecessary biopsies, simply because he finds significant tumor and not insignificant cancers.
"We know that men should undergo an MRI, when their first negative biopsy, but it is suspected that a patient has prostate cancer ", - he explained.
If in a subsequent MRI revealed nothing, "not to do anything", - he said.
On the contrary, if there is a significant MRI tumor image can guide the operator directly to the tumor, where an accurate sample biopsy, MRI-defined can be selected.
"It allows some patients generally avoid biopsies," - he said.
Nevertheless, Van Poppel found that the use of MRI to the standard biopsy in the United States less than in Europe, so some men may be sent for a biopsy, when it is not required.