The digital rectal exam identifies changes in the prostate, but PSA testing and MRI are other tests ordered by urologists in cases of suspected disease. If you have questions about prostate cancer diagnosis, don’t miss this guide we’ve prepared.
Among the tests to detect prostate cancer, the digital rectal exam is the most well-known. In this procedure, the doctor inserts a finger into the rectum and can thus identify changes in the prostate.
However, to confirm a prostate cancer diagnosis, the patient needs to undergo other tests, and that’s what we’ll talk about in today’s blog. Take this opportunity to clear your doubts.
Main tests for detecting prostate cancer
For the diagnosis of prostate cancer, the urologist generally recommends the digital rectal exam and the PSA test. Learn more about them below.
Digital Rectal Exam
The digital rectal exam is one of the main tests for diagnosing prostate cancer.
During the exam, the urologist inserts a lubricated gloved finger into the patient’s anus and examines the back and side parts of the prostate to check whether the size, texture, and shape of the organ are within normal limits.
The digital rectal exam generally does not require preparation and tends to be quick, causing minimal discomfort. Additionally, it is quick, lasting 10 to 15 seconds. The man should stand slightly bent over the office examination table, lie on his back, or lie on his side, depending on the doctor, who may ask the patient to bear down as if trying to have a bowel movement.
This exam should be part of the male check-up starting at age 45, but the Brazilian Society of Urology recommends that Black men or those with a family history have the exam starting at 40.
PSA Test
The PSA test is a blood test that measures the amount of Prostate-Specific Antigen, a protein produced by the prostate. The test should be part of the routine from age 45 or from age 40 if there is a cancer risk, such as father or brothers who had the disease before age 60.
There are two types of PSA tests, and both are important for the diagnosis of prostate cancer. Here are the differences:
- Total PSA: measures the total amount of PSA, combining the PSA bound to proteins and the free PSA in the blood;
- Free PSA: measures only the amount of PSA not bound to proteins, meaning it is free in the bloodstream. This test helps differentiate between benign conditions, such as benign prostatic hyperplasia, and prostate cancer.
Preparation includes:
- Avoid fatty foods, intense physical activities, and sexual activity 48 hours before the test, as all of these can temporarily increase PSA levels;
- Have not undergone a rectal exam or urethral catheterization 48 hours before;
- Have not used suppositories 72 hours before;
- Do not ride a motorcycle, bicycle, or horse 48 hours before the test;
- Check whether it is necessary to suspend continuous-use medications.
During the exam, the instructions are to remain relaxed and inform the nursing staff if you experience discomfort during or after the collection.
The interpretation of the PSA test is based on the following values:
- Normal: if it is below 4 nanograms per milliliter (ng/mL) of blood;
- Abnormal: the PSA is abnormal between 4.0 ng/mL and 10 ng/mL, and there is a possibility of prostate cancer.
If the value exceeds 10 ng/mL, the likelihood surpasses 50%.
Does ultrasound detect prostate cancer?
Many men wonder if ultrasound detects prostate cancer. The truth is that this exam is requested in case of abnormalities in the results of the rectal exam and PSA test. In other words, it is a complementary procedure to the rectal exam and PSA test.
There are two types of prostate ultrasound:
- Abdominal: identifies visible changes in size and appearance, and it is recommended when a prostate biopsy is not yet necessary. With the result, the doctor assesses whether a biopsy is needed.
- Transrectal: a lubricated probe is inserted into the rectum, and anesthetic may be used if the person has hemorrhoids. This exam captures clearer images of the prostate.
Preparation for prostate ultrasound includes:
- Laxatives or an enema 24 hours before the procedure;
- Drinking up to 1 liter of water 1 hour before the exam.
Does a urine test detect prostate cancer?
Currently, there is a urine test capable of detecting prostate cancer. The PCA3 test started as a project by USP scientists that involved the Medical Research Laboratory of the Urology Discipline of the USP School of Medicine, in partnership with the Institute of Biomedical Sciences.
The study analyzed 12 patients, 6 with cancer and 6 with benign prostate enlargement. The urine samples were 100% accurate in diagnosing prostate cancer. The full research is available in English.
The PCA3 test is already offered by laboratories and is indicated for men aged 50 and over, whose PSA result is high and when the biopsy is positive for prostate cancer.
Preparation consists of drinking 500 ml of water before the procedure. The healthcare professional collects 5 ml of urine after the rectal exam.
Which test confirms prostate cancer?
The biopsy is the test that confirms prostate cancer, and the procedure is performed by a doctor who collects small pieces of the prostate.
Complementary tests for early diagnosis
Computed tomography, magnetic resonance imaging, and bone scintigraphy are complementary tests that help in the early diagnosis of prostate cancer.
Magnetic Resonance Imaging
Multiparametric prostate magnetic resonance imaging is considered an effective test to aid in the diagnosis of prostate cancer, according to an article published by the Brazilian College of Radiology and Diagnostic Imaging.
Multiparametric prostate magnetic resonance imaging is also beneficial for patients treated with suspicions that the cancer has returned.
Biopsy
The prostate biopsy can be performed in laboratories or hospitals. The patient is sedated, and the procedure lasts approximately 10 minutes.
There are two ways to perform the procedure: through the rectal wall (transrectal) or through the perineum, the region between the scrotum and anus (transperineal).
Regardless of the method, the doctor uses small needles to collect small samples from 12 regions of the prostate.
Preparation for the exam includes the use of medications to clean the intestines and antibiotics to reduce the risk of infection.
A common reaction is blood in the urine, stools, and semen. However, it is not intense and improves within a week.
Prostate Health Index
The Prostate Health Index is a blood test that detects the likelihood of prostate cancer through a mathematical algorithm that combines the values of Total PSA, Free PSA, and p2PSA (proenzyme found in tumors).
Fasting is not necessary, and the preparation for the test includes:
1. 48 hours before the test:
- Not having undergone a urodynamic study;
- Sexual abstinence and no ejaculation;
- Not using a bicycle (stationary or regular);
- Not riding a motorcycle;
- Not riding a horse.
2. 72 hours before the test
- Not having used a suppository;
- Not having undergone urethral catheterization or rectal examination;
3. 5 to 7 days before
- Not having had a cystoscopy;
- Not having had a transrectal ultrasound;
- Not having had a colonoscopy or sigmoidoscopy;
4. 30 days before
- Not having had a prostate biopsy.
Men who have undergone total prostatectomy (complete removal of the prostate) only need to fast for three hours before the test.
PSE Test
The PSE Test (Prostate Screening EpiSwitch) is a new test for detecting cancer, developed by Oxford Biodynamics in partnership with the University of East Anglia (UK).
A pilot study with 147 men compared the results of the PSA test with the PSE test, and the PSE test showed promising results, with an effectiveness rate of 94% in detecting prostate cancer.
Scientists will conduct further analyses to confirm the results of the first phase. If validated, researcher Dmitry Pshezhetskiy states that the new PSE test “could significantly improve prostate cancer diagnosis.”
Which men should undergo prostate cancer diagnosis tests?
The rectal exam and PSA test, the main tests to detect prostate cancer, should be done starting at age 45 or starting at age 40 if a father or brothers had cancer before age 60.
However, the Ministry of Health states that screening is only recommended for men with risk factors.
How to prevent prostate cancer?
Adopting healthy habits is important for preventing cancer. Among them, include in your routine:
- Healthy diet;
- Physical exercises;
- Maintaining ideal weight for height;
- Avoiding smoking, alcohol, and drugs;
- Regular follow-ups with a urologist.
Diagnosis is essential to ensure treatment effectiveness
Studies indicate that when diagnosed early, prostate cancer has a high success rate in treatment. That’s why it’s so important to maintain healthy habits, have an annual follow-up with a urologist, and stay informed about health with Dr. Paulo Egydio’s tips on TikTok and Kwai.
Follow Dr. Paulo on all social media and actively take care of your health for a long and happy life.
