What is prostate cancer and what factors cause it to appear? Can it be prevented?
Prostate cancer is the most frequent tumor in men and the third in mortality, after lung cancer and colorectal cancer. It is a hormone-dependent tumor, specifically testosterone-dependent. Its genesis is not related to this hormone, but its treatment is.
The factors that cause its appearance are still to be determined, as it is not related to tobacco or other toxic risk factors. A few years ago there was speculation about the possible relationship that vasectomy could have with the appearance of cancer, but this could not be confirmed.
A known risk factor is obesity, since cholesterol metabolism has a clear relationship with the appearance of this cancer. Therefore, the preventive measures for this type of tumor would be general hygienic dietary measures, without the protective effect of any specific factor (for example, pumpkin seeds) having been demonstrated.
What techniques and advances have been developed to detect this type of cancer?
The early diagnosis of this tumor is one of the fields where most progress has been made, thanks to a marker such as PSA (prostate-specific antigen), which has allowed earlier detection of this type of tumor and the possibility of offering curative treatments.
The diagnosis of this tumor is always made by prostate biopsy. This is indicated according to the PSA, its absolute value, its relationship with the free PSA, its kinetics, etc.
Many advances are being made in this area to improve diagnosis. On the one hand we have molecular diagnostic techniques that allow us to further refine the indications for biopsy, such as urine tests (PCA3) and blood tests (PSA Score, ProPSA). On the other hand, imaging techniques, such as prostate MRI, and improvements in prostate biopsy offer us earlier and more precise detection of tumors.
What treatments and techniques are used to combat it?
There are different treatments that we divide into local, or with curative intent, and systemic, with the intention of controlling the cancer.
Among those with curative intent there are basically two: surgery and radiotherapy.
Surgery is performed in 3 different ways, open or traditional, laparoscopic or robotic. It consists of the removal of the prostate and seminal vesicles, and also of the lymph nodes (lymphadenectomy) when indicated. Erection nerves will be preserved in indicated cases.
There are no differences in the oncological results between the 3 techniques, but there are differences in the blood transfusion rate, which is higher in open surgery, as well as in recovery, which is faster with non-invasive techniques.
The most frequent complications are impotence and incontinence, which depend on the surgeon’s experience.
Radiotherapy can be external, by means of an electron accelerator, or interstitial (Brachytherapy), by means of a permanent implant of radioactive seeds in the prostate.
The side effects of radiotherapy, as in surgery, are impotence and incontinence, in addition to other complications derived from radiation such as cystitis and radicular rectitis, as well as urethral strictures.
Other options are energy treatments, such as cryotherapy, HIFU (high intensity ultrasound) and Irreversible Electroporation. These are minimally invasive local treatments. They are currently in the experimental phase and we only know results in the short and medium term.
As systemic treatments we have hormone therapy and chemotherapy.
Hormone therapy consists of a chemical castration of the patient to suppress the supply of testosterone.
What is the current prognosis for prostate cancer patients?
The prognosis of prostate cancer depends mainly on the stage of the cancer and its degree of differentiation. Cases are differentiated into 3 major groups: low, intermediate and high risk, depending on the PSA, digital rectal examination, and the Gleason grade of the biopsy. These groups give us a lot of information about the evolution of these patients.
The prognosis for patients in the low-risk group is excellent, and the chances of dying from prostate cancer are, in these cases, very low. On the contrary, for high-risk patients the expectations are worse, and they are likely to need more treatments in the future.