Prostate Cancer: Are We Not Overestimating The Role Of Screening And Treatment?

Over the past 10 years, the frequency of prostate cancer has increased significantly. The old standard method of diagnosis - digital rectal examination - was complemented by a widely used now to determine the level of prostate-specific antigen (PSA) in men 50 years and older. Undoubtedly, this method has become a major factor contributing to increased detection of prostate cancer. The discovery of seal, or nodular formation in the prostate during the digital rectal examination, elevated PSA, or both, suggesting the presence of prostate cancer in such cases in hospitals, clinics and urology offices conducting transrectal ultrasonography (U.S.) prostate cancer. However, ultrasound of the prostate –not an effective method for diagnosis of cancer, and is now widely used biopsy of the prostate gland under ultra sound using the so called biopsy guns

Such biopsies can be performed both in stationary and in the outpatient setting without anesthesia. Standard procedure is to obtain a biopsy of any suspicious area of the prostate, as well as from the following six areas: base, middle and edge segment on each side (polipozitsionnaya transrectal needle biopsy). If the biopsy reveals cancer, you can determine its pathological stage in Gleason's classification of the volume occupied by a cancerous tumor in each of the samples, and the total number of biopsies containing cancer cells. Thus it is possible to conduct a histological study of the different sections of the prostate, but the definition of tumor volume on biopsy is very approximate.

Recently, methods of early detection of prostate cancer undoubtedly improved. But is it good? Prove that overly active detection of prostate cancer is expensive and often leads to not compulsory treatment of tumors, which may be asymptomatic or not amenable to progression and the clinical recommendations of the American College of Physicians of NEWBORN prostate cancer highlighted the lack of evidence that digital rectal examination, PSA determination, transrectal ultrasonography and biopsy under ultrasound reduce mortality from prostate cancer. It is known that the accuracy and reproducibility of the digital rectal examination as a method of identifying the suspect seals in the prostate gland is not very high. The level of PSA may rise moderately in benign prostatic hyperplasia, and probably with age. Many disputes are and what are the indications for biopsy of the prostate, in which cases justify such treatments as radical prostatectomy or radiation therapy. Important factors influencing the choice of treatment for prostate cancer include pathological stage and tumor volume, age and overall health of the patient. However, the published data on disease outcome is not enough to create practical recommendations to make clinical decisions. As a result, powerful and uncontrollable national scale efforts aimed at diagnosis and treatment of localized prostate cancer.

The Expert Group of the American Urological Association, which develops practical recommendations for the management of patients with clinically localized prostate cancer, prepared a review of all published data on disease outcome in the use of radical prostatectomy, external beam therapy, short-distance radiotherapy, and expectant management. As shown by this review, to compare the clinical outcomes using all these methods can not, because each of them was used in very different populations Thus, according to urological research, the average age of patients who underwent radical prostatectomy, was equal to 62,7 years, and using delaying tactics - 70 years, ie the difference was 7.3 years. In patients who underwent radical prostatectomy, in 23% of cases the tumor was highly differentiated, in 57% - moderately differentiated and 20% - low-differentiated. In contrast, patients who had been used in the management of expectant management, 62% of cases the tumor was highly differentiated, 35% - moderately differentiated, and only 3% - the low-differentiated. Thus, these patients were generally older, and pathological stage of tumor they have often been lower. While waiting game for many of these patients was quite justified, we can not accurately compare the results of treatment for them and those patients in whom prostatectomy was performed. Due to the fact that the clinical characteristics of patients who received radiotherapy, and pathological stage are detectable tumors were quite different, comparing the results of treatment with clinical outcomes after radical prostatectomy or use expectant management is also not possible.

Evaluating the published data on clinical outcomes after treatment for prostate cancer should take into account the fact that almost all these data are based on survival curves of Kaplan-Meier. If the reported 5-year outcomes, only 13% of patients actually seen in 5 years, if we are talking about 10 - and 15-year outcome, the real figures are even lower. Thus, almost all data on clinical outcomes in cancer of the prostate cancer based on the results of monitoring of patients in just a few years. The validity of such extrapolations is highly questionable.

The Expert Group of the American Urological Association attempted to analyze all the published data on complications related to the treatment of localized prostate cancer. Such data were little, and the quality of their presentation leaves much to be desired. Many authors simply do not mention the complications. The frequency of complications in the different articles varies widely, various authors give different definitions of specific complications. Thus, the incidence of rectal after external beam radiotherapy, according to various sources, ranging from 16 to 55%. Although it is known that radiation proctitis mild or moderate severity occurs fairly often and usually passes quickly, is also known that it can be so severe that require the imposition of colostomy. However, the published data is difficult to determine how often proctitis is really becoming a serious problem.

After radical prostatectomy urinary incontinence often develops. Reports on the prevalence of this complication vary: incontinence associated with increased intra-abdominal pressure (eg, by coughing, sneezing, laughing, etc.), there is 50% of patients, and severe incontinence - at 0-15%, although in recent years, this complication rarely mentioned in articles. It should be noted that the interpretation of the significance of this outcome - a purely emotional issue. We (and probably most urologists) are considered minor intermittent urinary incontinence associated with stress, after surgery, as a mere trifle, not considering it a serious problem for those patients who are otherwise feeling well. Other authors (usually not urologists) consider any degree of postoperative urinary incontinence is extremely serious complication, significantly reduces the quality of life of the patient.
After radical prostatectomy is often seen as more painful complication for men - impotence, which is almost inevitable, if used surgical methods, you can not save the nerve fibers. When the biopsy results indicate the presence of tumor or the tops of both lobes of the prostate, may be advisable to conduct extensive removal of the prostate gland without saving the nerves. The patient must clearly understand the need for this and agree with the decision of a surgeon. An informed patient is almost always reconciled to the loss of potency, if aware of the need for expanded operations. In this sense the impotence - not so much complication, as the expected result of attempting to cure cancer. Fortunately, now there is a very reliable method of restoring erections after radical prostatectomy.

Thus, CM Coley et al faced with a formidable challenge: to determine the ratio of favorable and unfavorable effects of screening aimed at identifying prostate cancer. But now that this work has been completed and published, it seems to us that the model that these authors proposed to evaluate the feasibility of such screening, and treatment of localized forms of cancer, is not sufficiently reliable and not particularly useful. One of the published data CM Coley et al. focused, and many others excluded. Even the inclusion of studies to assess the clinical outcomes is not consistent with each other, since the group of patients receiving different treatment was significantly different, and methods of observation were imperfect. Therefore, we can not evaluate the actual clinical outcomes and, therefore, effectively determine the degree of risk, because data on complications arising from treatment also vary widely. It is easy to overstate the importance of some complications and diminish the importance of others.

Doctors are still making significant efforts to determine which prostate cancer most likely will be sluggish or clinically insignificant for the patient, and which require intensive treatment. Are we really helping the patient with strong statements for active intervention? Radical prostatectomy - an attractive method of treating relatively healthy in all other respects, men 50-60 years old with a tumor larger (at least with moderately differentiated adenocarcinoma), which probably does not extend beyond the capsule of the prostate gland. However, we do not know how wise it was a decision on the need of surgical treatment until they are removed and examined lymph nodes and tissue samples obtained during radical prostatectomy. But even if the tumor is limited outside the prostate gland, in the future it may recur. On the other hand, tumors that grow through the prostate capsule into the surrounding tissue or seminal vesicles, recur more often, although not necessarily. Radical prostatectomy provides a real opportunity to remove the entire tumor and to obtain histological material to predict the outcome of the disease and to evaluate the accuracy of preoperative diagnosis. In the case of radiotherapy, or expectant management, we will never know the true spread of the tumor, its volume and pathologic stage; such patients is difficult to compare with those who had underwent surgical treatment.

Further well-designed controlled studies to assess outcomes for different treatments will be very difficult and lengthy. It may be useful accumulation of accurate data, but also better organized and more prolonged period of observation. Since the treatment of prostate cancer is often accompanied by complications in the absence of reliable data on long-term outcome patients must be fully informed of the possible methods of treatment and actively participate in their choices. Now doctors are still far from having a formula, which would help to choose the most suitable treatment policy in each case.
In the meantime, we agree with the recommendation of the American Cancer Society, in accordance with which all men over 50 should perform an annual digital rectal examination to assess the prostate gland. We also agree that at the first examination should determine the level of PSA. If the PSA level is not elevated, and subsequent digital rectal examination did not reveal changes in the prostate, the determination of PSA can be repeated in 2-3 years.

Prostate cancer - an important social problem, the appearance of metastases adversely affects the organism as a whole, claiming many lives and is very expensive. We do not know whether the result will ultimately our efforts to reduce mortality from prostate cancer, but we hope so, especially in connection with a decrease in the incidence of metastatic prostate cancer. Only the significant and continuing efforts made to improve the diagnosis and treatment over time will bring us closer to our goal.