Diagnostic Ultrasound - Abdomen and Pelvis

Prostatic Carcinoma
Diagnoses: Urinary Tract
• PZ: Can cause ↓ signal on both T2WI and ADC map, may
also be hypervascular
Atrophy
• From normal aging or chronic inflammation
• Typically wedge-shaped areas of ↓ T2 signal and mildly ↓
ADC map signal from loss of glandular tissue (but typically
not as low as in cancer) ± contour retraction
Fibrosis
• Can occur after inflammation, may appear as wedge- or
band-shaped low signal on T2WI
Prostatic Intraepithelial Neoplasia (PIN)
• Dysplasia of epithelial lining of prostate glands
• Management of high-grade PIN is controversial; PCa
diagnosis on rebiopsy is similar to that in men whose initial
biopsies were normal
Atypia (a.k.a. Atypical Small Acinar Proliferation
[ASAP])
• Descriptive term: When needle biopsy shows findings
highly suspicious for, but not diagnostic of, PCa
• If other cores are negative, then short interval follow-up
rebiopsy, since ~ 40% of men with atypia will have PCa
diagnosed on rebiopsy
PATHOLOGY
General Features
• Etiology
○ Unknown: Advancing age, hormonal influence,
environmental and genetic factors play role
• Most common noncutaneous malignancy in western world,
2nd most common cause of cancer deaths among men
Staging, Grading, & Classification
• Staging based on TNM, PSA at time of diagnosis, and
Gleason score
• Grading by Gleason score: 2 values given; 1st is
predominant histologic pattern, 2nd is next most prevalent
histologic pattern; each value ranging from 1-5 (least to
most abnormal)
• T stage
○ T1: Clinically localized (tumor not palpable on DRE)
○ T2: Tumor confined to prostate
○ T3: Locally invasive beyond prostatic capsule
○ T4: Tumor is fixed or invades adjacent structures other
than seminal vesicles, such as external sphincter, rectum,
bladder, levator muscles, &/or pelvic wall
• N stage: N0: No nodal metastases, N1: Metastasis in
regional nodes
• M stage: M0: No distant metastasis, M1: Metastasis to
nonregional lymph nodes, bones, or other sites
Microscopic Features
• 95% of tumors are acinar adenocarcinoma
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Early: Asymptomatic, elevated PSA on screening
○ Advanced: Problems urinating, hematospermia,
hematuria, pelvic pain/discomfort, urinary incontinence,
erectile dysfunction, bone pain, rarely rectal obstruction
○ In general, most agree TRUS-guided prostate biopsy
should be performed when abnormal DRE or elevated
PSA (> 4.0 ng/ml)
– Complications of TRUS-guided prostate needle
biopsy: Sepsis (1-4%), hematuria (most common),
rectal bleeding, vasovagal episode, hematospermia
• Diagnosis: Pathology
• Current methods of prostate cancer detection: DRE, serum
PSA level, TRUS-guided biopsy ± MR
Demographics
• Age
○ Average age at diagnosis is 66, rare before age 40
• Ethnicity
○ African Americans > non-Hispanic whites > Asian
American and Hispanic/Latino
• Epidemiology
○ Heterogeneous disease, and most men with disease will
ultimately die of other causes
Natural History & Prognosis
• 5-year relative survival rates
○ Localized to prostate (AJCC stages I and II): Nearly 100%
○ Regional stage (AJCC stage III and stage IV cancers
without distant disease): Nearly 100%
○ Distant stage (rest of AJCC stage IV cancers = distant
disease): 28%
• Despite having higher volumes and PSA values at diagnosis,
TZ cancers are less likely to be associated with seminal
vesicle, extraprostatic and lymphovascular invasion
Treatment
• Management is complex due to difficulty in accurate
staging and in predicting speed of disease progression
• Options: Watchful waiting, targeted local therapies, radical
prostatectomy, various forms of radiation, hormonal
treatment, chemotherapy, combined approach
DIAGNOSTIC CHECKLIST
Image Interpretation Pearls
• Classic description of hypoechoic prostate lesion for PCa is
less valuable in PSA era when cancer is diagnosed earlier;
greater than 30-40% PCa are invisible on TRUS
SELECTED REFERENCES
1. Trabulsi EJ et al: Enhanced transrectal ultrasound modalities in the diagnosis
of prostate cancer. Urology. 76(5):1025-33, 2010
2. Trabulsi E, Halpern E, Gomella L. Ultrasonography and Biopsy of the
Prostate. In Campbell-Walsh Urology (10th ed., pp. 2735-2747).
Philadelphia:Saunders.
3. Harvey CJ et al: Applications of transrectal ultrasound in prostate cancer. Br
J Radiol. 85 Spec No 1:S3-17, 2012
4. Onur R et al: Contemporary impact of transrectal ultrasound lesions for
prostate cancer detection. J Urol. 172(2):512-4, 2004
5. Wollin DA et al: Guideline of Guidelines: Prostate Cancer Imaging. BJU Int.
ePub, 2015
6. Bouchelouche K et al: Advances in imaging modalities in prostate cancer.
Curr Opin Oncol. ePub, 2015
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