Cáncer de próstata: Las nuevas técnicas diagnósticas dan un vuelco al tumor
Prostate cancer is the development of cancer in the prostatea gland in the male reproductive system. Factors that increase the risk of prostate cancer include older age, a family history of the disease, and race. Prostate cancer screening is controversial. Many cases are managed with active surveillance or watchful waiting. Early prostate cancer usually has no clear symptoms.
Sometimes prostate cancer does cause symptoms, often similar to those of diseases such as benign prostatic hyperplasia. These include frequent urination, nocturia increased urination at nightdifficulty starting and maintaining a steady stream of urine, hematuria blood in the urineand dysuria painful urination. A study based on the Patient Care Evaluation in the US found that about a third of Prostata-Tumor diagnosed with prostate cancer had one or more such symptoms, while two-thirds had no symptoms.
Prostate cancer is associated with urinary dysfunction as the prostate gland surrounds the prostatic urethra. Changes within the gland, therefore, directly affect urinary function.
Because the Prostata-Tumor deferens deposits seminal fluid into the prostatic urethra, and secretions from the prostate gland itself are included in semen content, prostate cancer may also cause problems with sexual function and Prostata-Tumor, such as Prostata-Tumor achieving erection Prostata-Tumor painful ejaculation. Metastatic prostate cancer that has spread to other parts of the body can cause additional symptoms.
The most common symptom is bone painoften in the vertebrae bones of the spinepelvisor ribs. Spread of cancer into other bones such as the femur is usually to the proximal or nearby part of the bone.
Prostate cancer in the spine can also compress the spinal cord Prostata-Tumor, causing tingling, leg weakness and urinary and fecal incontinence. A complete understanding of the causes of prostate cancer remains elusive. Prostate cancer is very uncommon in Prostata-Tumor younger than 45, but becomes more common with advancing age.
The average age at Prostata-Tumor time of diagnosis is Prostata-Tumor Men who have first-degree family members with prostate cancer appear to have double the risk of getting the Prostata-Tumor compared Prostata-Tumor men without prostate cancer in the family.
In the United States in Prostata-Tumor, there were an estimatednew cases of prostate cancer and 30, deaths due to prostate cancer. Genetic background may contribute to prostate Prostata-Tumor risk, as suggested by Prostata-Tumor with race, family, and specific gene variants.
Men who have a first-degree relative father or brother with prostate cancer have twice the risk of developing prostate cancer, and those Prostata-Tumor two first-degree Prostata-Tumor affected have a fivefold greater risk Prostata-Tumor with men with no family history.
No single gene is responsible for prostate cancer; many different genes have been implicated. Two large genome-wide association studies linking single-nucleotide polymorphisms SNPs to prostate cancer were published in This SNP explains part of the increased prostate cancer risk of African American men as compared to American men of European descent, since the C allele is much more prevalent in the latter; this SNP is located in the promoter region of the MSMB gene, thus affects the amount Prostata-Tumor MSMB protein Prostata-Tumor and secreted Prostata-Tumor epithelial cells of the prostate.
Finally, obesity  and elevated blood levels of testosterone  may increase the Prostata-Tumor for prostate cancer. Consuming fruits and vegetables has been found to be of little benefit in preventing prostate cancer.
Prostata-Tumor blood levels of Prostata-Tumor D may increase the risk of developing prostate cancer. Folic acid supplements have no effect on the risk of developing prostate cancer.
There are also some links between prostate cancer and medications, medical procedures, and medical Prostata-Tumor. Infection or inflammation of the prostate prostatitis may increase the chance Prostata-Tumor prostate cancer while another study shows infection may help prevent prostate cancer by increasing blood flow to the area. In Prostata-Tumor, infection with the sexually transmitted infections chlamydiagonorrheaor syphilis seems to increase risk. Papilloma virus has been proposed Prostata-Tumor several studies to have a potential role in prostate cancer, Prostata-Tumor as Prostata-Tumor the evidence was inconclusive.
Although there is some evidence Prostata-Tumor prospective cohort studies that frequent ejaculation may reduce prostate cancer risk,  there are no results from randomized controlled trials concluding that this benefit exists. The prostate is a part of Prostata-Tumor male reproductive system that helps make and store seminal Prostata-Tumor. In adult Prostata-Tumor, a typical prostate is about 3 centimeters long and weighs about 20 grams. The prostate surrounds part of the urethrathe tube that carries urine from the bladder during urination and semen during ejaculation.
In prostate cancer, the cells of these prostate glands mutate into cancer cells. The prostate glands require male hormonesknown as androgensto work properly. Androgens include testosteroneProstata-Tumor is made in the testes ; dehydroepiandrosteronemade in the adrenal glands ; and dihydrotestosteroneProstata-Tumor is converted from testosterone within the prostate itself. Androgens are also responsible Prostata-Tumor secondary sex characteristics such as facial hair Prostata-Tumor increased muscle mass.
Most prostate cancers are classified as adenocarcinomasor glandular cancers, that begin when normal semen-secreting prostate gland cells mutate into cancer Prostata-Tumor. The region of prostate gland where Prostata-Tumor adenocarcinoma is most common is the peripheral zone. Initially, small clumps of cancer cells remain confined to otherwise normal prostate glands, a condition known as carcinoma in situ or prostatic Prostata-Tumor neoplasia PIN.
Although there is no proof that PIN is a cancer precursor, it is closely associated with cancer. Over time, these cancer cells begin to multiply and spread to the surrounding prostate tissue the stroma forming a tumor. Eventually, the Prostata-Tumor may grow large Prostata-Tumor to invade nearby organs such as the Prostata-Tumor vesicles or the rectumor the tumor cells may develop the ability Prostata-Tumor travel in the bloodstream and lymphatic system.
Prostate cancer is considered Prostata-Tumor malignant tumor because it is a mass Prostata-Tumor cells that can Prostata-Tumor other areas of the body. This invasion of other organs is called metastasis. Prostate cancer most Prostata-Tumor metastasizes to the boneslymph Prostata-Tumorand may invade rectum, bladder and lower ureters after local progression.
The route of metastasis to bone is thought to be venous Prostata-Tumor the prostatic venous plexus draining the prostate connects with the vertebral veins.
The prostate is a zinc -accumulating, citrate -producing Prostata-Tumor. The protein ZIP1 is responsible for the active transport Prostata-Tumor zinc into prostate cells. One of the zinc's important roles is to change the metabolism of Prostata-Tumor cell in order Prostata-Tumor produce Prostata-Tumor, an important Prostata-Tumor of semen.
The process of zinc accumulation, alteration of metabolism, and citrate production is energy inefficient, and prostate cells sacrifice enormous amounts of energy ATP in Prostata-Tumor to accomplish this task. Prostate cancer cells are generally devoid of zinc. This allows prostate cancer cells to save energy not making citrate, and utilize the new abundance of energy to grow and spread.
The absence of zinc is thought to occur via a silencing of the gene that produces the transporter protein ZIP1. The cause of the epigenetic silencing is unknown.
Strategies which transport zinc into transformed prostate cells effectively eliminate these cells in animals. Unfortunately, oral ingestion of zinc is ineffective since high concentrations of zinc into prostate cells is not possible without the active transporter, ZIP1.
Loss of cancer suppressor genes, early in the prostatic carcinogenesis, have been localized to chromosomes 8p10q13qand 16q. P53 mutations in the primary prostate Prostata-Tumor are relatively low and are more frequently seen in metastatic settings, hence, p53 mutations are a late event in the pathology of prostate cancer. RUNX2 is Prostata-Tumor transcription factor that prevents cancer cells from undergoing apoptosis thereby contributing to the development of prostate cancer.
The androgen receptor helps prostate cancer cells to survive and is a target for many anti cancer research studies; so far, inhibiting the androgen receptor has only proven to be effective in mouse studies. The American Cancer Society 's position regarding early detection by PSA Prostata-Tumor is "Research has not yet proven that the potential benefits of testing outweigh the harms of testing and treatment.
Starting at age 50, 45 Prostata-Tumor African American or brother or father suffered from condition before age 65 talk to your doctor about the pros and cons of testing so you can decide if testing is the right choice for you.
There are also several other Prostata-Tumor that can be used to gather more information about the prostate and the urinary tract.
Digital rectal examination DRE may allow a doctor to detect prostate abnormalities. Cystoscopy shows the Prostata-Tumor tract from inside the bladder, using a thin, flexible camera tube inserted down the urethra. Transrectal ultrasonography creates a picture of the prostate using sound waves from a probe in the rectum.
Prostata-Tumor the only test that can fully confirm the diagnosis of prostate cancer is a biopsythe removal of small pieces of the prostate for microscopic examination.
Ultrasound US and magnetic Prostata-Tumor imaging MRI are the two main imaging methods used for Prostata-Tumor cancer detection. Urologists use transrectal ultrasound during prostate biopsy and can sometimes see a hypoechoic area tissues or structures that reflect relatively less Prostata-Tumor the ultrasound Prostata-Tumor directed at them.
As ultrasound has Prostata-Tumor tissue resolution, it is generally not used clinically. Prostate Prostata-Tumor has better Prostata-Tumor tissue resolution than ultrasound. MRI in those who are at low risk might help people choose active surveillance; in those who are at intermediate risk it may help with determining the stage Prostata-Tumor disease, while in those who are at high risk it might help find bone disease.
Prostata-Tumor MRI is also used for surgical planning for men undergoing robotic prostatectomy. It has also shown to help surgeons decide whether to resect or spare the neurovascular bundle, determine return to urinary continence, and help assess surgical Prostata-Tumor.
If cancer is suspected, a biopsy is offered expediently. During a biopsy a Prostata-Tumor or radiologist obtains tissue samples from the prostate via the rectum. Prostata-Tumor biopsy gun inserts and removes special hollow-core needles usually three to six on each side of the prostate in less than a second.
Prostate biopsies are routinely done on an outpatient Prostata-Tumor and rarely require hospitalization. Antibiotics should be used to prevent complications like feverurinary tract infectionsand sepsis  even if the most appropriate course or dose of the antibiotic is still undefined.
The tissue samples are then examined under a microscope to determine whether cancer cells are present, and to evaluate the microscopic features or Gleason Prostata-Tumor of any cancer found. Prostate specific membrane antigen is a transmembrane carboxypeptidase and exhibits folate hydrolase activity. Tissue samples can be stained for the Prostata-Tumor of PSA and other tumor markers Prostata-Tumor order to determine the origin of malignant cells that have metastasized.
The oncoprotein BCL-2 is associated with the Prostata-Tumor of androgen-independent prostate cancer, due to its high levels of expression in androgen-independent tumours in advanced stages of the pathology. The upregulation of BCL-2 after androgen ablation in prostate carcinoma cell lines and in a castrated-male Prostata-Tumor model further established a connection between BCL-2 expression and prostate cancer progression. The expression of Ki by immunohistochemistry may be a significant predictor of patient outcome for men with prostate cancer.
An important part of evaluating prostate cancer is determining the Prostata-Tumoror how far the Prostata-Tumor has spread. Knowing the stage helps define prognosis and Prostata-Tumor useful Prostata-Tumor selecting therapies. Its components include the size of the Prostata-Tumor, the number of involved lymph nodesand the presence of any other metastases. The most important distinction Prostata-Tumor by any staging system is whether or Prostata-Tumor the cancer is still confined to the prostate.
Several tests can be used to look for evidence of spread. Medical specialty professional organizations recommend against the use Prostata-Tumor PET scansCT scansor bone scans when a physician stages early prostate cancer with low risk for metastasis. Bone scans should reveal osteoblastic appearance due to increased bone density in the areas of bone metastasis Prostata-Tumor to what is found in many other cancers that metastasize.
After a prostate biopsy, a Prostata-Tumor looks at the samples under a microscope. If cancer is present, Prostata-Tumor pathologist reports the grade of the tumor.