Although it is the most frequent tumor in men -with more than 35,000 cases per year in Spain-, affecting mainly patients over 65 years of age, and represents the second cause of death from cancer in our environment, prostate cancer continues to be in some unknown aspects. “We speak of prostate cancer when the cells of the prostate – a gland that only men have and that produces part of the liquid that forms semen – begin to grow out of control”, explains the head of the Urology Service at Hospital Universitari Joan XXIII of Tarragona, Dr. Josep Segarra. Thus, as to what contributes to this uncontrolled growth, he himself points to “genetic alterations and factors that we still do not know” as causes.
Based on the fact that the disease is usually asymptomatic, “its existence can be suspected when there are alterations in digital rectal examination and/or prostate-specific antigen (PSA), a protein produced by prostate cells and that is detected in blood”, details the doctor. On the other hand, in more advanced cases of the disease, urinary discomfort, blood in the urine or bone pain can be added to the symptoms.
“We have overcome the reluctance that existed when it came to going to the specialist’s office by men”
Dr. Josep Segarra, head of the Urology Service at the Joan XXIII University Hospital in Tarragona
In this sense, “when a digital rectal examination is performed, palpable indurations of the prostate are sought and if detected, a biopsy will be performed, regardless of the PSA value in the blood.” But the head of the Urology Service clarifies that the protein is specific to prostate tissue, but not prostate cancer. “The fact of having high PSA values does not mean that they correspond to malignant prostate cells, since benign ones also produce PSA, that is, having high values does not necessarily mean suffering from prostate cancer,” he says.
Thus, when the values are between 4 and 10 ng/ml, it is necessary “to take into account other parameters, such as the patient’s age, prostate volume or even an MRI of the prostate, tests that help decide that the patient is a tributary of a biopsy, since it is the only test to arrive at a confirmation diagnosis”. In this sense, Dr. Segarra indicates that “PSA can give rise to false positives when it comes to large or inflamed prostates, or false negatives in the early stages of the disease, when the tumor is small”.
In addition to being related to age -the incidence being 80% in men over 80 years of age, although the clinical incidence is lower-, There are also hormonal (testosterone) and racial (affects African-Americans more than Caucasians) risk factors that must be taken into consideration, to which must be added the “discussed environmental and dietary factors, for which a diet rich in fruits, vegetables and cereals”, indicates the doctor.
Regarding genetic factors, 9% of prostate cancers are familial. “We refer to these cases when three or more relatives are affected or there are two diagnosed before the age of 55”, details the head of the Urology Service, adding that “there is also an association between prostate cancer and the existence in the familial breast cancer or ovarian cancer”.
Today, prostate cancer cannot be prevented, so early detection is essential, although it is not without some controversy. In this sense, the European Association of Urology recommends digital rectal examination and PSA determination biannually to all asymptomatic patients from 50 years of age (45 years if there is a family history) up to 70-75 years, provided there are between 10- 15 years of life expectancy and as long as the patient is informed and accepts the benefits and the risk. “Fortunately, we can say that we have already overcome the reluctance that existed when it came to going to the specialist’s office on the part of men and that the population is increasingly aware of the need for self-care,” says the doctor.
“With the current understanding of the biology of prostate cancer and its natural history, we have learned that some low-risk prostate cancers do not require immediate aggressive treatment. Many of these patients will not die from their cancer,” says Dr. Segarra.
On the relationship between this paradigm shift and prostate cancer, in recent years, the treatment of the disease includes what is called ‘active follow-up’. “It consists of not treating the patient diagnosed with low-risk prostate cancer immediately, and only doing so if a deterioration or progression of the parameters that are monitored for the tumor is observed during the protocolized follow-up. At this point, the patient is offered radical prostatectomy or radiotherapy”, details the specialist. “Currently, at the Hospital Universitari Joan XXIII we have more than a hundred patients in active follow-up, whose purpose is to avoid overtreatment and, preserving the quality of life, the survival of patients,” says Dr. Segarra.
The value of research
For all these reasons, research is essential. In this regard, the head of the DIBIOMEC group (Biomarkers of diseases and molecular mechanisms) of the Institut d’Investigació Sanitària Pere Virgili (IISPV), Dr. Matilde Rodríguez Chacón, details that “what is of interest is finding a good biomarker for early diagnosis and of prognosis that helps urologists decide which treatment is best for each patient.
Although the prostate-specific antigen (PSA) biomarker has been the most widely used in the last three decades, the researcher points out that “other biomarkers are needed to help make better decisions.” In practice, he continues to explain, “there are a number of genetic markers that help predict the degree of tumor aggressiveness, as well as tests that measure multiple biomarkers in biofluids, but their use is not yet recommended.”
“We are interested in finding a good biomarker for early diagnosis and prognosis that helps urologists decide which treatment is best for each patient”
Matilde Rodríguez Head of the DIBIOMEC group of the IISPV
Thus, the DIBIOMEC group -created in 2016 and which brings together clinical researchers from the Department of Urology, Pathological Anatomy and basic scientists-, “In 2019, a panel of non-invasive prognostic biomarkers was found, which allows the aggressiveness of the tumor to be assessed and guides the most appropriate treatment, but it does not prevent a biopsy to confirm the diagnosis, since a patient without histological confirmation of cancer cannot be treated of prostate. With only blood and semen samples, seven markers could be identified and the aggressiveness of the tumor predicted with a 91% success rate”, as explained by the doctor and head of the DIBIOMEC group.
In an effort to improve the prognostic panel, the research group continued to recently reduce three biomarkers from a single fluid – semen – to predict tumor aggressiveness. A line of research endorsed by various international publications, awards, scholarships and two patents on which they continue to work today, since, concludes Dr. Matilde Rodríguez Chacón, “we are interested in finding a biomarker that, in addition to being non-invasive and economical, It can be used with a high percentage of success applicable to aggressive tumors and avoid overtreating patients with indolent tumors and thus improve their quality of life”.