Prostate cancer

Description:

Cancer prostatic zhelezyobychno arises at men 50-60 years are more senior. It occurs at persons of young age seldom. The exception is made by prostate sarcoma. This seldom found disease affects young people and even meets at children's and youthful age that connect with an embryonal etiology of a tumor. The probability of detection of a prostate cancer at the man aged from 40 up to 59 years makes 1:78 (1,28%), aged from 60 up to 79 years - 1:6 (15,6%). In general about 3% of men have chance to die of a prostate cancer.

In structure of oncological diseases of a number of the countries the prostate cancer takes the 2-3rd place, and in the USA came to the 1st place. In Great Britain the prostate cancer takes the 2nd place among all oncological diseases at men. The prostate cancer takes the 2nd place after a skin melanoma, considerably surpassing malignant diseases of a lung and stomach.

Symptoms of the Prostate cancer:

The clinical picture of a prostate cancer depends on a process stage. Allocate the localized, locally-spread and generalized prostate cancer. Carry to the localized prostate cancer I (T1a-sn0m0) and II (T2a, bN0M0) stages of tumoral process, i.e. tumors limited to the prostate capsule without its invasion and without the regional and remote metastasises. The locally-spread prostate cancer includes the III stage (T3a-bN0M0). Existence of the regional or remote metastasises is characteristic of generalized process. Such division dictates the accurate choice of an optimum way of treatment among the existing numerous methods of therapy. A problem of diagnosis after verification is definition of the patient in one of these three groups. At early stages patients practically do not show complaints. On later the symptom complex of a prostate cancer is connected with two main displays of a disease: symptoms of obstruction of the lower uric ways (the speeded-up and complicated urination, a sluggish stream of urine etc.) and the symptoms caused by spread of a tumor (a hamaturia, pain). Symptoms of obstruction of the lower uric ways at a prostate cancer meet quite often. In addition to a prelum it is also connected by an urethra tumor with the fact that at most of patients at the age of 60 years and is more senior the accompanying prostate hyperplasia takes place. Therefore at inspection of patients with adenoma of presteel gland it is always necessary to exclude a prostate cancer. The locally-spread prostate cancer can sprout mouths of ureters that one is shown - or a bilateral ureterohydronephrosis, pyelonephritis and a chronic renal failure (such patient showed a transdermal nephrostomy). The hamaturia is noted in the IV stage of a disease (T4) and is connected with germination of a tumor in a bladder. In certain cases the prostate cancer can burgeon in distal department of a rectum and squeeze its gleam. Then the disease will be shown by a lock, tenesmus, bleedings, up to colic impassability. If the tumor of a prostate burgeons in surrounding fabric, also the lymphostasis with further effects is possible. Emergence of the remote metastasises changes also clinical implication of a disease. The main symptom which forces the patient to see a doctor is pain which develops at metastasises in bones. Localization of pain usually corresponds to localization of a metastasis, except for extremities where pain can be conduction because of a prelum of nervous roots at metastatic damage of a backbone. Pain tends to gradual strengthening. Especially sharp pain arises at pathological changes.

Reasons of the Prostate cancer:

Distinguish genetic predisposition, the progressing hyperplasia of a prostate and influence of cancerogenic factors from etiological origins of a prostate cancer. It is noted that a prostate cancer Europeans and Americans, than the people of the Asian continent have much more often. Today it is difficult to define, than it is caused: character of food, national culture, way of life or something other. There are data that meal, saturated with animal fats and rich with calories, promotes development and progressing of a prostate cancer. The highest risk of development of this disease in men who consume in a large number milk, cheese, eggs and meat. Much less often vegetarians are ill. The inhibiting influence of a soy and rice diet, and also regular long reception of vitamin E is noted (and - tocopherol). The low maintenance of some microelements (selenium, zinc) increases risk of a disease of a prostate cancer.

The disease pathogeny in many respects is defined by function of gonads and concentration of male sex hormones (androgens) in blood serum. However sexual activity does not influence risk of development of a prostate cancer. Androgens are growth-promoting factors, of development and functional activity of gland it is normal. With age at men in a prostate production of the enzyme of 5-a-reductase which is responsible for transfer of testosterone in dihydrotestosterone that it leads to increase of level of the last in gland fabrics increases. Dihydrotestosterone in turn induces synthesis of an insulinopodobny growth factor in prostatic cells. The dihydrotestosterones and an insulinopodobny growth factor formed in enough affect autocrinely a stromal cell, and also in the paracrine way reach epithelial cells of a prostate, strengthening in them synthesis of RNA of proteins. Thus, the increased content of dihydrotestosterone in a prostate quite can be one of releasers of both high-quality, and malignant hyperplastic processes. With opening of a gene of HPC 1 (a hereditary prostate cancer 1) on a chromosome 1 predisposition of the person carrying this gene to a prostate cancer is proved.

Depending on a form, character of an arrangement of ferruterous structures in tumors and ratios of epithelial and connective tissue components histologically distinguish a number of types of cancer. If the prostate cancer arises from a ferruterous epithelium, it is called an adenocarcinoma if from a flat epithelium - planocellular. Tubular cancer develops from the narrow channels covered by an epithelium (cubic or prismatic) in which gleam there can be a secret. Alveolar cancer arises at the expense of trailer departments of the branching glands. These are the so-called differentiated cancer forms.

Cancer most often (90%) develops from peripheral departments of a prostate while a hyperplasia - from the central and tranzitorny areas. In 5-25% of cases the combination of cancer and hyperplasia of a prostate is noted.

Cancer therapy of a prostate:

Verification of the diagnosis of a prostate cancer is at the same time followed by establishment of a stage of a disease that defines the nature of future treatment. For a process stadirovaniye most often use ultrasonic scanning of a prostate, MRT of bodies of a small pelvis (including a dynamic magnetic and resonant prostatovezikulografiya), KT (more rare), an osteostsintigrafiya.

At early stages of a prostate cancer the main medical strategy are applied: dynamic observation, a radical prostatectomy and radiation therapy (remote radiation therapy or brachytherapy), the transrectal high-intensity focused ultrasonic ablation of a prostate (HIFU). In a stage of development there are a cryotherapy and laser therapy.

The radical prostatectomy is considered an optimum method of treatment of the localized prostate cancer. According to literature it is known that 10-year survival after a radical prostatectomy makes 80-90%. Surgical treatment has a number of undoubted advantages in comparison with other methods: radical oncotomy, exact stadirovaniye of process, long bezretsidivny survival. The radical prostatectomy is absolutely shown to patients with cancer of a prostate of I and II stages which expected life expectancy makes 10-15 years, and is a choice method at this category of patients. Before a radical prostatectomy at patients with the localized and locally-spread prostate cancer it is possible to apply neoadjuvant hormonal therapy.

Among postoperative complications erectile dysfunction or an incontience of urine most often can develop. After a radical prostatectomy the lethality is low, but deduction of urine and a potentiality considerably depend on technical features of operation and experience of the surgeon.

The radiotheraphy is carried out by means of outside radiation with focusing on a prostate or implantation of special radioactive capsules through a crotch directly to a prostate under control of transrectal ultrasonic scanning (brachytherapy). Radiation therapy is effective at the cellular level, influencing structure of DNA. It leads to loss by a cell of ability of reproduction, she grows old and dies. Against the background of remote radiation therapy at patients complications can develop. The acute effect of radiation therapy on area of a basin can cause diarrhea, irritations in a rectum and a dysuria. The brachytherapy, or implantation of radioisotopes, provides higher radiation level in a prostate at a smaller exposure dose of surrounding bodies, than usual radiation therapy. Higher intraprostatichesky dose promotes effective elimination of a tumor with the smallest percent of complications.

For treatment of locally-spread forms of a disease use generally conservative methods (hormonal therapy and remote radiation therapy). In treatment of such forms of a disease of "the gold standard" the maximum androgenic blockade which is directed to reduction of content in testosterone blood as the prostate cancer is a hormonedependent tumor is. For this purpose use as monotherapy (a bilateral orkhiektomiya, an estrogenoterapiya, anti-androgens), and the combined treatment including a castration combination (surgical or medicamentous) with anti-androgens (флутамид, flutsiny). Testicles produce about 95% of all androgens therefore their removal causes effective decrease in testosterone. In addition to surgical castration there are some more possible mechanisms of an androgenic deprivation: medicamentous castration (estrogen, antagonists of the factor luteinizing hormone-rileasing), androgenic blockade of cells of targets (steroid anti-androgens, pure anti-androgens). In last years most widely estrogen was applied to cancer therapy of a prostate. However estrogen has toxicity to the cardiovascular system which is shown not only in their influence on metabolism of lipids, but also on system of coagulation and increase in volume of liquid. Natural complications of treatment by estrogen are dysfunction of a myocardium, liver, a hypernatremia, arterial hypertension, a gynecomastia. Now these drugs use only in the presence of bone metastasises.

The maximum androgenic blockade includes a simultaneous exception of testicular and adrenalny androgens as the 1st line of hormonal cancer therapy of a prostate. The maximum androgenic blockade can be reached in various ways: castration or any other principle of treatment which excludes products of testicular androgens in combination with an exception of adrenal androgens or in the place of products, or in target cells. At the patients receiving therapy by anti-androgens it is also reasonable to determine the DOG level. Its increase demonstrates progressing of a disease and about need to change the nature of treatment.

Most often the prostate cancer metastasizes in pelvic bones and a backbone. Characteristic changes define at a X-ray analysis of pelvic bones and lumbar department of a backbone at their metastatic defeat which carry more often osteoblastic, the osteolytic or mixed character is more rare. Owing to alternation of osteoblastic and osteolytic sites of pelvic bones have a spotty, marble appearance. Epidural metastasises are a usual complication of a system and widespread prostate cancer. In view of tendency of a prostate cancer to innidiation to vertebralny and juxtaspinal areas, probability of a compression of a spinal cord it is high. Early diagnosis and treatment of epidural metastasises is shown on purpose perhaps longer preservation of motive function, and also function of intestines and bodies of a small pelvis. All patients with a constant dorsodynia and the revealed involvement of a backbone, existence or lack of neurologic symptomatology which make risk on an epidural compression should conduct radiological examination. Apply the bisfosfonata strengthening bone structure and interfering demineralization of a bone to stopping of a pain syndrome and prevention of secondary changes. The most effective drug of this group is zoledronovy acid (zometa).

The chemotherapy of a prostate cancer has auxiliary value because of low sensitivity of a tumor to the available himiopreparata. This type of therapy is applied at treatment of gormonrezistentny forms of a generalized prostate cancer.