Diagnosis

Prostate Cancer

Diagnosis

The diagnosis of prostate cancer is made by a series of tests:

• PSA determination. This is a blood test in which the level of PSA (prostate specific antigen), a substance that the prostate produces naturally, is determined. There are no normal PSA values, but age, prostate size and number of previous biopsies must be considered. In general, a PSA less than 1 is considered optimal at any age. If a PSA greater than 2.5 is found, it could be a sign of infection, inflammation, enlargement or prostate cancer.
• Digital rectal examination. It is performed to explore the consistency and size of the prostate. If any irregularities in the texture, shape or size of the gland are found, other tests may be needed.
• Urine test. A urine sample is drawn to determine if there is hematuria (blood in the urine) or any other abnormality.

Complementary tests

If any abnormalities are detected in the above tests, other tests, such as the following, may be ordered to determine if you have prostate cancer:

• Multiparametric magnetic resonance imaging of the prostate. It is a non-invasive test in which multiple images of the prostate and its behavior are obtained. MRI yields a risk of harboring prostate cancer -the PIRADS classification- ranging from 1 (very low) to 5 (very high). This technique also makes it possible to visualize only those tumors that are going to be of clinical significance or put the patient's life at risk. MRI also provides very useful information on tumor size, the size of the prostate, tumor staging, its exact location in the prostate, etc.
• Prostate biopsy: Consists in the insertion of a fine needle into the prostate with the intention of extracting part of its cellular tissue and analyzing it. This analysis makes it possible to confirm or rule out the presence of cancerous cells in the prostate.
• Prostate biopsy by image fusion. When there is a PIRADS grade 3 or higher lesion, an ultrasound-guided biopsy is usually performed in which a 3D model is generated in real time, guiding the sampling thanks to the MRI images. This test makes it possible to know exactly what tumor is present, how far it reaches and its degree of aggressiveness in order to design a personalized treatment for each patient. Fusion prostate biopsy not only allows the fusion of images from multiparametric magnetic resonance imaging (MRI), but also PET images, with which a functional assessment of the tumor can be made.
• Microultrasound. This is a new technology that makes it possible to replace multiparametric magnetic resonance imaging (MRI).It allows real-time visualization of the prostate and guided biopsies. In this way, itis possible to detect tumors that the MRI does not detect and facilitates the visualization of the peripheral zone of the prostate. If a suspicious area is detected during the test, a biopsy can be performed at the same time.

How to know the stage of prostate cancer?

When the biopsy confirms the existence of prostate cancer, the next step is to determine its level of aggressiveness (grade). A higher grade indicates a more aggressive cancer that is more likely to metastasize or spread rapidly. In order to determine the aggressiveness of the tumor, techniques used include:

• Gleason score. This is the most common grading system for prostate cancer and helps to separate less aggressive tumors from more aggressive tumors. The grade is a number from 1 to 5, with 1 being the most well-differentiated pattern (looks more like normal cells) and 5 being the most poorly differentiated (looks more abnormal). A primary grade is assigned to tumor cells that make up the majority of the tumor and a secondary grade to cells that make up a minority of the tumor. The Gleason score is therefore the sum of these two plus dominant grades. So the potential range of Gleason scores is from 2 (1+1), non-aggressive cancer, to 10 (5+5), very aggressive cancer.

In addition to these tests, diagnostic tests that facilitate the detection of prostate cancer before the onset of symptoms are also available today: pro-PSA, 4kallikreins, PCA-3, MDX and others.

How to know if there is metastasis of prostate cancer?

Once the diagnosis has been confirmed, if there is suspicion that the cancer may have spread beyond the prostate, imaging tests such as abdominal CT and bone scan may be recommended to rule out the presence of lymph node involvement, organ involvement and bone metastasis.