• There is a significant decline in prostate
cancer related mortality: d/t early prostate
cancer detection programs.
• Role of PSA screening efforts, introduction
& refinement of systematic transrectal
ultrasonography (TRUS)– guided prostate
biopsy techniques, and increased public
awareness about prostate cancer.
• TRUS of the prostate- first described by
Watanabe et al(1968).
• TRUS-guided systematic sextant biopsy
protocol- introduced by Hodge et al(1989).
• TRUS: mainstay of many image-guided
prostate interventions, including prostate
biopsy, brachytherapy, cryotherapy, & high-
intensity focused ultrasonography (HIFU),
evaluation of appropriate patients for treatment
ANATOMY OF PROSTATE
• The prostate lies
neck and urogenital
anterior to rectum,
an ideal position to
be imaged by
• On the basis of pathologic zonal architecture,
prostate is divided into:
Anterior fibromuscular stroma (AFS) that is
devoid of glandular tissue,
transition zone (TZ),
central zone (CZ),
periurethral zone, and
peripheral zone (PZ).
• But these regions are not visible
sonographically as distinct entities.
• Normal CZ and PZ(posterior):
majority of adenocarcinomas;
• TZ(anterior) is more heterogeneous.
• Most common imaging modality for
• Most commonly used for:
prostate cancer detection,
evaluation of other conditions such as
directing the biopsy of prostate cancer.
A, In the transverse plane with the hypoechoic urethra centrally located
(star) and dotted line representing transverse measurement.
B, Midline sagittal view with the hypoechoic urethra running the length of
the gland, D1 represents longitudinal and D2 anteroposterior measurement.
Seminal vesicles and vasa
deferentia in the transverse plane
• Endorectal probes available in both
side- and end-fire models; transmits
frequencies of 6 to 10 MHz.
• Newer biplane probes provide
simultaneous sagittal and transverse
• Increasing frequency yields increased
• The commonly used 7-MHz transducer
produces a high-resolution image with a
focal range from 1 to 4 cm from the
transducer (best for PZ where most
• Lower frequency transducers (e.g.older 4-
MHz) have a focal range from 2 to 8 cm
but at lower resolution; they improve
anterior delineation of large glands,
increasing the accuracy of volume
measurements, but provide poor internal
• Medium-gray image of normal PZ
serves as the "reference point" for
judging lesions as hypoechoic (darker
than the normal PZ), isoechoic
(similar to the normal PZ),
hyperechoic (lighter than the normal
PZ), or anechoic (completely black).
• TRUS should be performed in both
transverse and sagittal planes.
• π/6 × transverse diameter × AP
diameter × longitudinal diameter
• Mature average prostate-20-25 g and
remains constant until age 50.
• For more accurate determination of
prostate volume (Brachytherapy),
Planimetry is required.
IMAGING ON TRUS
• All hypoechoic lesions within the PZ: consider
• A hypoechoic lesion is malignant in 17-57% of
cases, but they are not pathognomonic for
• Lack of a distinct hypoechoic focus doesn't
preclude biopsy, as 39% of Ca prostate cases
are isoechoic, & 1% hyperechoic on
conventional gray scale TRUS.
• Granulomatous prostatitis, prostatic
infarct & lymphoma- all may produce
• Extracapsular extension of prostate
cancer, although not well visualized if
present as a microfocus, is suggested by
a focal loss of the typically bright white
Classic hypoechoic peripheral zone (PZ) lesion
(dotted line) in the right midgland that transrectal
ultrasonography–guided biopsy proved to be a
Gleason 3 + 3 = 6 adenocarcinoma.
TRUS without Biopsy
• Treatment planning volume measurements:
brachytherapy, cryotherapy, BPH therapy
• Volume measurement during hormonal downsizing
for EBRT or brachytherapy
• Placement of fiducial markers for EBRT
• Evaluation of azoospermia: ejaculatory duct cysts,
seminal vesicle cysts, etc.
• Therapeutic aspiration or unroofing of prostatic
cysts; drainage of prostatic abscess
• Diagnosis of suspected symptomatic prostate cancer (i.e.,
bone metastasis, cord compression)
• Screening for prostate cancer in asymptomatic patient >
age 50 with > a 10-year life expectancy (if strong family
history or if African-American, consider screening at age
Prostate nodule or significant prostate asymmetry
regardless of PSA level
PSA > 4.0 ng/dL regardless of age
In men < age 60 to 65 years, consider biopsy if PSA > 2.5
If PSA > 0.6 ng/dL at age 40
Increased PSA velocity (>0.75 ng/dL/year)
Free PSA in considering initial biopsy with PSA < 10
ng/mL: >25% no biopsy; >10% and <15%, consider
biopsy; <10%, biopsy
• Prior to intervention in symptomatic
BPH (e.g., surgical therapy or initiation
of 5α-reductase inhibitors)
• Prior to cystoprostatectomy or
orthotopic urinary diversion
• To diagnose failed radiation therapy
before use of second-line therapy
• Follow-up biopsy (3-6 months) after
diagnosis of high-grade PIN or ASAP.
• Data from the Prostate Cancer
Prevention Trial have shown that no safe
PSA threshold can rule out prostate
cancer in any age range.
• For a serum PSA value between 4.0 and
10.0 ng/mL, using a % free PSA
threshold of <25% allowed detection of
95% of cancers while eliminating 20%
• Volume-based PSA parameters
evaluated to reduce confounding from
• These include:
PSA density (PSAD; PSA divided by
complexed PSA density (complexed
PSA divided by prostate volume), and
PSA transition zone density (PSA
divided by transition zone volume).
• PSA levels between 4 and 10 ng/mL
and a normal DRE:
PSAD ≥ 0.15- prostate biopsy
PSA transition zone volume was the
parameter with highest overall
sensitivity & specificity.
PSA Dynamics/PSA Velocity(PSAV):
• Rate of change in PSA.
• With PSA levels between 4-10 ng/mL, PSAV
≥ 0.75 ng/mL/year: a specific marker for the
presence of prostate cancer.
• In PSA <4, PSAV > 0.5ng/mL/yr is
• PSAV may play a role in the prediction of life-
threatening prostate cancer .
• A PSAV > 0.35 ng/mL/year 10-15 years prior
to diagnosis- fivefold increased risk of life-
threatening prostate cancer more than a decade
• Significant coagulopathy
• Painful anorectal conditions
• Severe immunosuppression, and
• Acute prostatitis.
• Written, informed consent.
• All anticoagulant therapy (warfarin,
clopidogrel, aspirin/NSAIDs, herbal
supplements) should be stopped 7-10
days before prostate biopsy.
• For coagulopathic pts., INR
correction below 1.5.
• decreases the amount of feces in the
rectum, thereby producing a superior
acoustic window for prostate
• may reduce bacterial seeding of the
• Topical lidocaine jelly.
• Infiltration anesthesia around nerve
• Direct infiltration(Intraprostatic
• Skin & subcut.infiltration for
• Left lateral decubitus position with knees
and hips flexed 90 degrees.
• Lithotomy position preferred for
transperineal biopsies, brachytherapy
treatment planning, or placement of fiducial
gold markers for external-beam therapy.
• Lithotomy position is preferred when color
Doppler imaging is used to identify areas of
hyperemia for targeted biopsy of the
prostate(distribution of color Doppler flow
within the prostate is dependent on patient
TRUS PROSTATE BIOPSY
• Assess prostate volume.
• Prostate imaging in transverse &
sagittal planes(from base to apex).
• Note location and characteristics of any
lesions (i.e., hypoechoic, hyperechoic,
calcifications, contour abnormalities,
• A spring-driven, 18-gauge, needle core
biopsy device or biopsy gun, passed
through the needle guide attached to
the ultrasound probe.
• Biopsy gun advances the needle 0.5 cm
and samples subsequent 1.5 cm of
tissue with the tip extending 0.5 cm
beyond the area sampled.
• one core, bilaterally,
each from base, mid,
• samples both PZ &
• Vast majority of
TRUS BIOPSY SCHEMES
EXTENDED CORE BIOPSY
• Improved cancer detection rates by
incorporating additional laterally
directed cores into the standard
systematic sextant technique.
• At present, 6 cores are considered
inadequate for routine prostate
biopsy for cancer detection.
• TZ and SVs are not routinely sampled(low
yields for cancer detection at initial biopsy).
• TZ and anteriorly directed biopsies may
occasionally prove necessary to diagnose
prostate cancer in patients with persistently
elevated PSA levels and prior negative
• A role for TZ biopsies in men with gland size
> 50 mL, with an additional yield of 15%
• Seminal vesicle biopsy is not routinely
performed unless there is a palpable
abnormality, when PSA value > 30, or
if brachytherapy is being considered.
Various reported systematic biopsy schemes.
A, Sextant biopsy scheme originally proposed by Hodge and
associates (Hodge et al, 1989b)
B, The 10-core biopsy of Presti and coworkers (2000).
C, The 12-core, or double sextant, biopsy.
D, The 13-core “5-region biopsy” of Eskew and colleagues
REPEAT PROSTATE BIOPSY
• Use of a 2nd
prostate biopsy in all cases
of a negative finding on initial biopsy is
• But 3rd
repeat biopsies should
only be obtained in selected patients
with high suspicion of cancer and/or
poor prognostic factors on the 1st
• Overall cancer detection rates for repeat
prostate needle biopsy with various biopsy
templates ranges from 10% - 38%.
• Indications for a repeat prostate biopsy
include the following:
1) A highly suspicious DRE (digital rectal
2) A persistently rising serum PSA (> 0.4 –
3) A low free PSA (certainly < 10%, maybe <
22% - 25%)
4) Presence of PIN or atypia on prior biopsy
ADVANCED USG TECHNIQUES
FOR PROSTATE IMAGING
COLOR & POWER DOPPLER TRUS:
• Color Doppler imaging is based on
the frequency shift in the reflected
sound waves from the frequency of
• depicts the velocity of blood flow in
a directionally dependent manner.
• Color assignment is based on the direction
of blood flow related to the orientation of
the transducer receiving the signal; flow
toward the transducer- red and flow away
in shades of blue; color is not specific for
arterial or venous flow.
• Top image, solid white arrow
depicts hypoechoic lesion
within the peripheral zone
concerning for prostate cancer.
• Lower image depicts
hypervascular area seen with
color Doppler imaging, yellow
and red area corresponds to the
hypoechoic area seen on the
POWER DOPPLER IMAGING
(enhanced color Doppler, color
amplitude imaging [CAI], or color
• uses amplitude shift to detect flow in
a velocity and directionally
• Advantages: ability to detect slower
flow and to have less reliance on the
Doppler angle, making it more
suitable for detection of prostate
A. Color Doppler transrectal ultrasonography (TRUS) and
B. Power Doppler TRUS identify a Gleason 4 + 4 = 8
adenocarcinoma in the left midgland
• Patients with detectable color Doppler
flow within their dominant tumor at the
time of TRUS-guided biopsy are at a
10-fold increased risk for PSA
recurrence after radical retropubic
CONTRAST ENHANCED TRUS(CE-TRUS):
• Intravenous microbubble ultrasound contrast
agents, infused systemically during gray-scale and
TRUS Doppler imaging amplify flow signals within
the microvasculature of prostate tumors, allowing
selective visualization of malignant foci.
• These agents increase the echogenicity of the
intravascular space on grey-scale imaging and
provide a dramatic visible increase in the Doppler
• These are constructed with air or higher-molecular-
weight gas agents encapsulated (albumin or
polymer hard shell, lipid- or surfactant-coated) for
• CE-TRUS + 3D IMAGE
RECONSTRUCTION of enhanced
• GREY-SCALE HARMONIC imaging:
better spatial & temporal resolution.
• FLASH REPLENISHMENT
IMAGING: improved visualisation of
Unenhanced color (A) transrectal ultrasonography (TRUS) and power Doppler (B)
TRUS fail to detect evidence of an underlying malignancy. After infusion of a
microbubble contrast agent, color (C) TRUS and power Doppler (D) TRUS
demonstrate an area of increased flow in the left midgland that proved to be a Gleason
3 + 4 = 7 adenocarcinoma on targeted biopsy
ARTIFICIAL NEURAL NETWORKS
• New sonography technique.
• employs real-time sonographic imaging of
the prostate at baseline and under varying
degrees of compression.
• Through computerized calculations,
differences in displacement between
ultrasonic images from baseline and during
compression may be visualized, and regions
with decreased tissue elasticity may be
tagged as suggestive of malignancy.
Elastography demonstrates an area of decreased compliance in the right base
consistent with an underlying malignancy (blue near arrow). Note color scale
in upper right corner indicating relative tissue “firmness.” Targeted biopsy of
this region revealed a Gleason 4 + 4 = 8 adenocarcinoma
ENDORECTAL MRI & MR
• MRSI identifies biochemical changes
within the tissue that may predate the
appearance of histological changes.
• MRSI suggestive of malignancy may
not have biopsy detectable PCa at the
time of MRSI but may develop
histological cancer at a later date.