As for the PSA level to determine the presence of prostate cancer?
Detection of prostate cancer at an early stage of development before the appearance of clinical manifestations is a major challenge facing oncologists. Certainly, many have heard that there are such substances as tumor markers. Increasing their quantity in the blood indicates the presence and progression of malignant tumors in a particular organ. The reliability of many of the tumor markers is in the range of 50-60%. However, the increase of PSA levels in prostate cancer almost always indicates the presence of cancer in this gland (the confidence level is 90%).
What is a DOG
This abbreviation stands for as the prostate specific antigen. PSA is a tumor marker for prostate cancer, by which it is possible to detect cancer at the preclinical stage of development. For the first time this substance was discovered in 1979 in the seminal fluid. Since 1987, the determination of this tumor marker in the blood has revolutionized the diagnosis of prostate cancer at an early stage. Thanks to this radical surgery allow to fully cure patients.
Prostate specific antigen is normally present in the body of every man. This substance is produced in the prostate gland and is necessary for the liquefaction of semen. A small amount of PSA gets into the bloodstream and there are constantly circulates in two forms: free and bound (combined with plasma proteins).
At what level of PSA in the blood should raise the alarm
A normal prostate specific antigen in the blood is 2 to 6.5 ng/ml depending on age:
- 40-49 years 2.5 ng/ml;
- 50-59 years 3.5 ng/ml;
- 60-69 years, 4.5 ng/ml;
- Years 70-79 is 6.5 ng/ml.
Increased this indicator more than 10 ng/ml is a direct indication for prostate biopsy and full examination of the patient, in fact, significantly increases the probability of having cancer. After that, with a positive histological response, it is necessary to conduct radical surgery, if possible.
Related article: Common DOG – the norm analysis in men
The increase in the amount of PSA in the blood more -6,5 2,5 ng/ml (the norm at different ages own) and 10 ng/ml indicates a possible presence of the pathology of the prostate gland. To determine the need for biopsy was calculated by the ratio of free prostate specific antigen to total. It is believed that the presence of cancer in the blood increases the amount of bound forms of tumor marker and falls – free Rule is when the ratio of free to total exceed 15%. Reduction pokazatelja is an indication for biopsy and possibly later the operation.
Howeverthe level of prostate specific antigen in the blood may increase after exposure to a number of reasons. Learn more about them we will discuss in the next section.
What can affect the level of tumor marker in blood
Let's first understand how the amount of substance can increase in the blood stream. There are two options: the first is the increase of production of the gland that occurs with prostate cancer, the second – increased penetration in the vasculature on the background of the normal functioning of the prostate gland.
The last option is of particular interest, let us examine it in detail. If there is inflammation directly in the gland there is an increase in vascular permeability and damage to the body. Due to this, a greater amount of PSA is absorbed into the bloodstream compared to the norm.
Upon the occurrence of BPH also increases the level of tumor marker, in particular. This is due to several reasons. First, this pathology increases the size of the body. A large gland produces more prostate specific antigen, simple as that. Second, the expanding adenoma compresses the blood vessels and healthy tissue, resulting in formation of foci of ischemia and heart attacks. All this increases the level of tumor marker in blood.
Recommendations for determining the level of PSA in the blood
In addition to the above reasons, the level of prostate specific antigen affected by various medical manipulations and even ejaculation. So pay attention to the following points before donating blood for tumor markers to avoid false positive result:
- To conduct the research you need at least 3 days after massage of the prostate.
- You need to abstain from ejaculation for 2 days before testing.
- Conducting transrectal ultrasound of the prostate also significantly affect the result, so this procedure is carried out at least a week before the test.
- After biopsy of the organ, the level of tumor marker, you can define a minimum of 6 weeks.
- Only after half a year you can get a true result on the level of prostate specific antigen in the blood during such operations as transrectally resection of the prostate.
Determination of the level of prostate specific antigen in the blood is a great way for early diagnosis and treatment control of malignant tumors in the prostate gland. This method is quite informative.
But there are many factors that can give false-positive response and to mislead, both Clinician and patient. Therefore, it is only through patient explanation of the nuances of preparation for bloodtumor marker, carefully collected anamnesis, objective and instrumental methods of examination you can set the correct diagnosis.