SON 2112 Ultrasound of the Abdomen Part II Prostate Holdorf SON 2112 Ultrasound of the Abdomen Part II

Outline Normal Anatomy Terms and Landmarks Zonal Anatomy Classifications of Prostate Cancers Image Orientation Prostate Cancer Indications for Transrectal Ultrasound Laboratory Values Sonographic Appearance Transrectal Ultrasound Prostate Staging Benign Prostatic Hyperplasia (BPH) Prostate Volume Treatments

Common uses of Prostate Sonography Transrectal ultrasound of the prostate gland is performed to: Detect disorders within the prostate. Determine whether the prostate is enlarged, with measurements acquired as needed for any treatment planning. Detect an abnormal growth within the prostate. Help diagnose the cause of a man's infertility.

A transrectal ultrasound of the prostate gland is typically used to help diagnose symptoms such as: A nodule felt by a physician during a routine physical exam or prostate cancer screening exam. An elevated blood test result. Difficulty urinating.

Patient Prep Patient should wear comfortable, loose-fitting clothing for the ultrasound exam. Patient may be asked to wear a gown during the procedure. Patient may be instructed to avoid taking blood thinners, such as aspirin, for seven to 10 days prior to the procedure if a biopsy is planned. An enema may be taken two to four hours before the ultrasound to clean out the bowel. The ultrasound image is immediately visible on a video display screen that looks like a computer or television monitor. The image is created based on the amplitude (strength), frequency and time it takes for the sound signal to return from the area of the patient being examined to the transducer and the type of body structure the sound travels through. For ultrasound procedures requiring insertion of the transducer, such as transvaginal or transrectal exams, the device is covered and lubricated.

The Procedure The prostate gland is located directly in front of the rectum, so the ultrasound exam is performed transrectally. For a transrectal ultrasound, the patient is asked to lie on his side with his knees bent. A protective cover is placed over the transducer; it is lubricated, inserted through the anus and placed into the rectum. The images are obtained from different angles to get the best view of the prostate gland. If a suspicious lesion is identified with ultrasound or with a rectal examination, an ultrasound-guided biopsy can be performed. This procedure involves advancing a needle into the prostate gland while the radiologist or urologist watches the needle placement with ultrasound. A small amount of tissue is taken for microscopic examination.

Done with the Basics

Transrectal ultrasound (TRUS) of the prostate initially was thought to be the gold standard test for the prostate, providing clinically important information of benign and malignant conditions, including prostatic hyperplasia, prostatitis, obstructive infertility and prostate cancer evaluation including screening, diagnosis, biopsy, staging and monitoring of response to therapy. Over time, the strengths and limitations of transrectal ultrasound have become better defined. Patients today are mainly referred for TRUS related to cancer evaluation and biopsy. Transrectal ultrasound was initially considered a primary screening test for prostate cancer. This has now been replaced by prostate specific antigen (PSA) and digital rectal examination. Occasionally, patients are referred for TRUS for infertility and prostatitis.

Normal Anatomy The prostate is located in the retroperitoneum and is bordered: Anteriorly by the pubic bone Posteriorly by the rectum Superiorly by the urinary bladder Inferiorly by the urogenital diaphragm The inferior vesical artery is typically the arterial supply to the prostate with branches from the internal iliac artery.

The prostate gland diagram

The prostate gland diagram

The inferior vesical artery

Image Orientation Transrectal ultrasound (TRUS) produces transverse and sagittal images. With Transrectal Sonography, the image is inverted to maintain standard medical imaging orientation. The rectum is displayed at the bottom of the screen.

Orientation- MRI and Ultrasound

Terms and Landmarks APEX- inferior portion of the gland situated superior to the urogenital diaphragm. BASE-Superior portion of the gland situated below the inferior margin of the urinary bladder. SEMINAL VESICLES: Two Sac-like out-pouchings of the vas defferens situated adjacent to the superior/posterior aspect of the prostate, between the urinary bladder and rectum.

EJACULATORY DUCTS: Duct that passes through the central zone and empties into urethra. This duct originates from the combination of the vas defferens and the seminal vesicles. VERUMONTANUM: A longitudinal ridge within the urethra in which the orifices of the ejaculatory ducts are located on either side.

Seminal Vesicles

Seminal Vesicle Cyst

Seminal Vesicles ultrasound Transverse and Bow-tie appearance

Ejaculatory Duct

Ejaculatory Duct Cyst Ejaculatory duct obstruction

CORPORA AMYLACEA-calcifications commonly seen in the inner gland of the prostate. SURGICAL CAPSULE-demarcation between the inner gland (central and transitional zones) and the outer gland (peripheral Zone). EIFFEL TOWER SIGN-is shadowing created by calcification in the area of the urethra and Verumonianum.

Corpora Amylacea

The Eiffel Tower Sign-central zone The Eiffel Tower Sign-central zone. In the center shows the urethra, which looks like the Eiffel tower.

Eiffel Tower Sign

Surgical Capsule Benign Prostatic Hypertrophy–Calcifications Surgical Capsule Benign Prostatic Hypertrophy–Calcifications. An angled transverse scan through the left base region of the prostate demonstrates calcifications, associated with benign prostatic hypertrophy, along the surgical capsule (small arrows). The peripheral zone (p) is normal. Note the normal sharp demarcation of the prostate (curved arrow) from the periprostatic fat.

Zonal Anatomy (McNeal) The original concept of a 5-lobed prostate has been replaced by McNeal’s concept of zonal architecture. The prostate glandular zones include the following:

Peripheral zone Posteriorly located portion of the prostate containing 70% of the prostatic glandular tissue, thus it is the location of mot prostate cancers. Central zone Superiorly located portion of the prostate containing 25% of the prostatic glandular tissue. Ejaculatory ducts pass through this zone from the seminal vesicles to the urethra. Transition zone Contains 5% of the prostatic glandular tissue. It is the site of origin of benign prostatic hyper plasia (BPH). Fibromuscular zone Anteriorly located non-glandular portion of the prostate. Non-glandular tissue; thus, it is not affected by cancer, prostatitis or hyperplasia.

Prostate anatomy

Right lateral zone anatomy

Zonal prostatic anatomy

The normal Prostate as it appears with ultrasound

Possible warning signs of prostate problems Frequent urination, especially at night. Difficulty starting or stopping urination. Weak or dribbling stream. Not able to urinate. Pain or burning sensation when urinating. Blood in the urine or semen. Constant pain in the lower back, pelvis, or upper thigh

The Four Stages of Prostate Cancer Stages A and B: Cancer is confined to the prostate Stages C and D: Cancer has spread outside the prostate. Symptoms Fatigue Pain in bones Weight loss Low RBC count Urinary obstruction

Classification (Grading) of Prostate Cancers Gleason Score is the most commonly used system of classifying the histological characteristics of prostate cancer. It predicts the aggressiveness of the disease.

Gleason Score

Prostate Cancer The incidence of prostate cancer in the US is approximately 200,000 cases per year with a mortality of 30,000 cases per year. Risk factors include: Age >80% of prostate cancers are diagnosed in men older than 65 years. Race African American men are 2 times more likely to develop prostate cancer than white men. Genetics First-degree relative up to 2-3 x greater risk of developing prostate cancer.

Indications for Transrectal US. Abnormal digital rectal exam Elevation of PSA (>4.0 ng/ml) Prostate-specific antigen. PSA (an enzyme) is present in small quantities in the serum of men with healthy prostates, but is often elevated in the presence of prostate growth, hence may be an indicator of prostate cancer.

Laboratory Values Prostate Specific Antigen (PSA) PSA (an enzyme) increases with age and prostate volume. Elevation occurs with benign conditions such as prostatitis and BPH, and with prostate cancer. Prostate cancer will elevate PSA 10x greater than BPH.

PSA levels < 4 ng/ml* Normal 4 - 10 ng/ml Benign/Potential Malignancy >10 ng/ml Most likely cancer There are also age and volume adjusted PSA levels. * Ng/ml is an indication of concentration. Ng stands for nanograms. ml stands for milliliters. It shows how much solid substance there is in any particular milliliter of liquid.

PAP- Prostatic Acid Phosphatase Elevated in association with prostate carcinoma. Not used as routine screening test as it may be elevated with other conditions.

The Sextant Biopsy method

Sonographic Appearance of prostate cancer Prostate cancer may have a varied appearance depending on the size of the lesion (focal vs. diffuse) and background of the prostate (normal vs. hyperplastic). Although prostate cancers can appear as hyperechoic, isoechoic, or hypoechoic, the CLASSIC appearance of prostate cancer in ultrasound is a hypoechoic, peripherally-oriented lesion.

Keep in mind that not all cancers are hypoechoic, and not all hypoechoic lesions are cancerous. The larger the lesion and the higher the PSA level, the more likely hypoechoic lesion will be a cancer.

Prostate cancer

Prostate Cancer: Transverse transrectal ultrasound image of the prostate shows tumor in the left base(white arrow). The tumor is hypoechoic relative to normal prostatic tissue.

Prostate Cancer : transrectal ultrasound scan: large bilateral peripheral zone hypoechoic area—extensive carcinoma in the peripheral zone (arrows).

Transrectal Ultrasound (TRUS) Since the introduction of PSA screening, the role of TRUS has been limited to aid in guided needle biopsy. Pre exam preparation may include: Cleansing enema Pre and post prophylactic antibiotics. The patient is placed in the left lateral lithotomy or knee-elbow position.

Lithotomy position for a prostate biopsy.

Methods of prostate biopsy. Lesion directed biopsy Biopsy based on a sonographic lesion is infrequently used due its poor detection rate. Systematic Sextant Biopsy Hodge et al demonstrated that taking systematic biopsies ( 3 on right and 3 on left) that the cancer detection rate was superior to the lesion-directed method. Parasagittal Sextant Biopsy To improve on the traditional sextant biopsy method, urologist are including additional biopsy cores in the lateral aspects of the peripheral zone.

Coronal schematic representation of sextant biopsy technique, including sampling of both the peripheral and central zones. Arrows indicate areas of biopsy sampling.

Prostate Staging/cancer Staging is used to determine the type of treatment for prostate cancer and is an indicator of prognosis. Clinically non-palpable Palpable nodule confined to prostate Palpable nodule extending through capsule Metastases

Treatments for prostate cancer Treatment options include Watchful waiting Hormonal therapy Radiation treatment Cryotherapy: the use of extreme cold in surgery. surgery

Brachytherapy Permanent prostate brachytherapy (seed implants) is a prostate cancer treatment that uses ionizing radiation to destroy cancer cells. The radioactive material is placed either directly into a malignant tumor or very close to it, thus the term brachytherapy, which means short therapy in Greek. Radiation kills the tumor by destroying the DNA within the cancer cell. When the cancer cell attempts to divide and reproduce itself, it is unable to do so because the DNA is no longer intact and as a result, the prostate cancer dies.

Seed implant sites

Benign Prostatic Hyperplasia BPH is an enlargement of the prostate that occurs in the peri-urethral and transitional zones of the gland. Symptoms include: Difficult initiation of voiding Urinary frequency Small stream BPH is an enlargement of the inner gland which is hypoechoic relative to the peripheral zone.

BPH

Prostate Volume Prostate volume is utilize to determine PSA density (volume adjusted PSA) and to better determine the best method of treatment. Prostate volume formula Volume =height x width x length x 0.52

Reason for determining prostate volume: Ultrasound Volume Estimation is the typical procedure that doctors use to ascertain the size, interpret the type and elevation of PSA levels. This procedure will also be used after the doctor has employed a course of anti-cancer treatment, to determine if the course of action is effective against the prostate cancer. The UVE can use different techniques to determine volume, ranging from planimetry measurements (cross-sectional imagining across a plane of the prostate) or based on its diameter.

Name the four zones of the prostate What zone of the prostate is the source of most prostate cancers? What zone of the prostate is not affected by cancer? Describe Benign Prostatic Hyperplasia (BPH).

Anatomical Spatial Relationships 5.The ejaculatory ducts pass through the ______________ and empties into the urethra. 6.Seminal vesicles are two sac-like out-pouchings of the vas deferens situated adjacent to the __________ aspect of the prostate between the urinary bladder and the rectum. 7.The base of the prostate id the ______________ portion of the gland. 8.The apex of the prostate is the _______________ portion of the gland. 9.The demarcation between the inner gland and the outer gland is called the ___________.’

The prostate is situated in the retroperitoneum and is bordered: 10.Anteriorly by the ____________ 11.Posteriorly by the ____________ 12.Superiorly by the ____________ 13.Inferiorly by the ____________ 14.Describe Prostate-Specific Antigen. (PSA) 15.When do PSA levels rise?