anatomy of prostate and prostate carcinoma

1. Prostate Cancer
Dr Rojan Adhikari
FCPS II resident
General Surgery
Kathmandu Model Hospital

3. Anatomy
• Male accessory reproductive organ
• Conical fibromuscularglandular organ, surrounding the
proximal urethra
Zonal anatomy (Mc Neal)
• Peripheral zone : lies mainly posteriorly and from which
must carcinoma arise and constitute of 70% of prostatic
glands
• Transitional zone: periuretheral, BPH arises
• Central zone: lies posterior to the urethral lumen and
above the ejaculatory duct

7. Lobes
Zones

8. Capsules of prostate
• True capsule
Prostate is surrounded by a fibrous capsule
which contains prostatic plexuses of nerve and
vein
• False capsule
Visceral layer of pelvic fascia forms a fibrous
prostatic sheath outside the true capsule

9. Blood supply
• Inferior vesical artery
• Derived from the internal iliac artery
• Supplies blood to the base of the bladder and
prostate
Nerve supply
• Neurovascular bundle
• Lies on either side of the prostate on the rectum
• Derived from the pelvic plexus , arising from the
S2-4 and L1-2 nerve roots
• Important for erectile function.

10. Lymphatic drainage
• Primarily drains to the obturator and the
internal iliac lymphatic channels.
• There is also lymphatic communication with
the external iliac, presacral, and the para-
aortic lymph nodes.

11. Secretion of prostate
• The prostatic fluid makes up about one-third
of the total volume of semen and contains
various enzymes, zinc and citric acid.

12. EPIDEMIOLOGY
• Prostate adenocarcinoma is the 2nd common malignancy in
males.
• Accounting for 15% of all cancers diagnosed
• Affects men older than 50 years (Median age 68 yrs)
• Second leading cause of cancer deaths in men after lung carcinoma.
• Higher incidence – Scandinavia, North America, Australia, western
and northern Europe
• Low incidence Asian countries

15. NATURAL HISTORY
LOCAL GROWTH PATTERN
• Almost all prostatic carcinomas (>70%) develop in the PZ and
BHP (>90%) arises from the TZ (McNeal)
• Small tumors tend to occur in the anteromedial gland, adjacent
to the fibromuscular stroma, whereas larger, more advanced T
stage tumors are often located in the posterior gland near the
prostatic capsule
• Multifocality is characteristic of prostate cancer 77% (Jewett)
• PZ cancers spread along the capsular surface of the gland, and
may extend through the capsule of the gland, invade seminal
vesicles and periprostatic tissues, and involve the bladder neck or
the rectum.

16. CLINICAL MANIFESTATIONS
EARLY STAGE
Asymptomatic
Cancer is in the peripheral zone
LOCALLY ADVANCED DISEASE
Obstructive / irritative voiding
Retention of urine
Hematuria
Renal failure
Pelvic pain

17. METASTATIC DISEASE
Bone pain
Spinal cord compression symptoms
Paraperesis

18. LOWER URINARY TRACT SYMPTOMS
• Voiding
hesitancy, poor flow, Intermittent stream, sense
of poor bladder emptying, dribbling, episode of near
retention.
• Storage
Frequency, nocturia, urgency, urge incontinance,
nocturnal incontinance
Hematuria prostatic urethra/ trigone involvement
Hematospermia

19. • Extra prostatic spread often asymptomatic/ extensive disease.
• Rectal involvement
 Hematochezia
 Constipation
 Intermittent diarrhoea
 Abdominopelvic pain
• Renal impairment due to prolonged BOO
• Fluid retention/ electrolyte imbalance

20. • Involvement of neurovascular bundles or corporeal bodies –
Impotence/ pelvic pain/ priapism
• Advanced disease metastatic symptoms
• Bony pain / pathological fracture/ Spinal tendernesss
• Spinal cord compression neurological deficits/ sensorymotor
changes/ bladderbowel dysfunction
• Pelvic / Paraaortic Lymph node edema of abdominal wall,
genitalia or lower extrimities/ mass abdomen
• Adrenal/ lung/ skin metastasis
• PNS SIADH/ Cushing syndrome/ Hematologic

21. PHYSICAL EXAMINATION
DRE cornerstone of the physical examination
 Sim’s lateral prone/ Lithotomy/ Kneechest/ Standing
• Typical finding ca prostate Hard, nodular,
asymmetrical may or may not be raised above the surface of
gland and is surrounded by compressible prostatic tissue
Prostatic induration BHP nodule/ calculi/ infection/
granulomatous prostatitis/ infarction

22.  DRE
 Specificity 50% and Sensitivity 70%
 Only 2550% of men with an abnormal DRE have cancer

23. DIAGNOSTIC WORKUP
Laboratory
Complete blood cell count, blood biochemistry
Serum PSA (total, free, percentage free)
Plasma acid phosphatases (prostatic/total)
Radiographic imaging
• Transrectal ultrasonography (for biopsy guidance)
• Biopsy/Needle biopsy of prostate (transrectal, transperineal)
• Chest radiograph (high risk for metastatic disease)
• Computed tomography of pelvis
• Radioisotope bone scan (PSA >20)
• Magnetic resonance imaging with endorectal coil

24. Diagnosis
• Signs and symptoms of Prostatism
• Abnormal DRE: although correlates poorly with the
volume and extent of cancer, an integral part of the
algorithm.
• Serum PSA: usually > 4 ng/ml
With increasing PSA level, chance of getting cancer
increases, but less likely to be organ confined.
• TRUS guided Biopsy:
1) to establish the diagnosis.
2) to report extent and grade of cancer in each core.
3) to document presence of metastasis

25. Screening
• A Cochrane review published in 2013, presents the main overview
to date. The findings of the updated publication (based on a
literature search until April 3, 2013) are:
• Screening is associated with an increased diagnosis of PCa (RR:
1.3; 95% CI: 1.02-1.65).
• Screening is associated with detection of more localised disease
(RR: 1.79; 95% CI: 1.19-2.70) and less advanced PCa (T3-4, N1,
M1) (RR: 0.80, 95% CI: 0.73-0.87).
• From the results of five RCTs, randomising more than 341,000
men, no PCa-specific survival benefit was observed (RR: 1.00, 95%
CI: 0.86-1.17). This was the main endpoint in all trials.

27. PROSTATE SPECIFIC ANTIGEN
• Serine protease glycoprotein secreted by prostatic
epithelium
• Carcinoma specific
• Normal ~0.4 4 ng/ml (upper limit2.6 ng/ml)
• t1/2 ~ 2.2±0.8 ― 3.2±0.1 days
• Mild elevation 4- 10 ng/ml
• Significant >10ng/ml
• Sensitivity ― 85%, Specificity – 6570%
• Estimated rate of cancer detection by PSA screening
1.83.3%
• Carcinoma with normal PSA ― 25%

28. Benign causes for an elevated PSA
• Benign prostatic hyperplasia
• Acute prostatitis
• Subclinical inflammation
• Prostate biopsy
• Cystoscopy and TURP
• Urinary retention
• Ejaculation
• Digital rectal examination
• Perineal trauma

29. Normal PSA according to age
• 40 to 49 years – 0 to 2.5 ng/mL
• 50 to 59 years – 0 to 3.5 ng/mL
• 60 to 69 years – 0 to 4.5 ng/mL
• 70 to 79 years – 0 to 6.5 ng/mL

30. PSA
• Range % of carcinoma
• 410 25
• >10 60 (localized 50%)
• >50 high suspicion of carcinoma
with LN mets/ bone mets or
disseminated disease

31. PSAD (PSA Density)
 Cancers produce less PSA per cell than nonmalignant
prostatic tissues
• PSA density calculates the ratio of prostate size to
PSA
• A higher PSA density- high chance of malignancy
• BHP ― 0.3ng/ml/gm
• Ca prostate― 3.3ng/ml/gm

32. Prostate cancer antigen 3 gene (PCA3)
• Ratio of PCA3 mRNA over prostate-specific
antigen (PSA) mRNA,
• Determined from a urine specimen collected
after a vigorous digital rectal examination.
• sensitivity ranged from 53 to 84 percent and
specificity ranged from 71 to 80 percent.
(Urology. 2010;75(2):447)

33. PSAV (PSA Velocity)
• Serial PSA measurements and calculate the
rate of rise in PSA
• Accurately measuring PSA velocity requires
three serial readings, ideally with the same
assay, obtained over at least a 12- to 24-
month period
• A rate of rise of >0.75 ng/ml/yr a/w a higher
frequency of cancer

34. Fractionated PSA
• PSA can be measured in two serum
components, either conjugated or free.
• The percentage of free PSA relative to the
total PSA can be informative,
• high ratio (>30 percent) - normal,
• low ratio (<10 percent) is more commonly
associated with prostate cancer.

35. Four kallikrein assays
• Total PSA, free PSA, intact PSA, and human
kallikrein-related peptidase 2 are incorporated
into a testing panel to increase detection of
aggressive cancers.
• The 4K score Test combines the blood test results
with age, DRE findings, and previous biopsy
results.
• A large prospective study showed that the
4Kscore Test had an AUC of 0.82 for detecting
cancers with Gleason score ≥7

36. [-2]ProPSA or p2PSA
• Specific isoform of the PSA proenzyme proPSA
• The Prostate Health Index (PHI) is a derived
measure that incorporates %[-2]ProPSA, free PSA,
and total PSA.
• While the use of the %[-2]ProPSA and PHI might
reduce unnecessary biopsies for men with PSA
values between 2 and 10 ng/mL.
Clin Chem Lab Med. 2013 Apr;51(4):729-39

37. N Engl J Med. 2009 Mar 26;360(13):1320-8. doi: 10.1056/NEJMoa0810084. Epub 2009 Mar 18.
Conclusion:
PSA-based screening reduced the rate of death from prostate
cancer by 20%.

38. PSA + DRE
• DRE - detection rate of 3.2 percent,
• PSA – detection rate 4.6 percent,
• PSA + DRE -- 5.8 percent
(J Urol. 1994;151(5):1283)

39. PROSTATIC ACID PHOSPHATASE (PAP)
• Normal 05.5 u/l
• Sensitivity 10%
• Specificity90%
• Abnormal PAP correlates with higher tumor
stage

40. IMAGING
CXR
– Pulmonary metastasis
– Miliary pattern
Axial skeletal survey : Specific sites of bony pain
– Osteoblastic secondaries
USG abdomen-pelvis:
• hydroureteronephrosis
• large post void residual urine volume
• retroperitoneal lymphadenopathy
• Liver mets.

41. TRANRECTAL
ULTRASONOGRAPHY(trus)
• TRUS of the prostate, first described by
Wantanabe (1968)
• Normal adult prostate : Symmetric, triangular,
relatively homogenous structure with an
echogenic capsule
• All hypoechoic lesions within the PZ should be
noted and included in the biopsy material in
suspicion of malignancy.

42. TRUS
– Staging of clinically localized prostate cancer
– Guidance during the seed/interstitial
brachytherapy
– Monitoring prostate
– Evaluation and aspiration of prostate abscess
– Monitoring the response to prostate cancer
treatment

43. TRUS Guided biopsy of the prostate
• Gold standard for diagnosis of prostate cancer
Recommendation: TRUS guided Bx in patients
with PSA> 4 ng/ml
• To establish the diagnosis
• To report extent and grade of each core
• To document presence of Pelvic LN
involvement and ECE

44. Accuracy 58%
 Extraprostatic extension
 Sensitivity66% Specificity 46%
 Seminal vesicle invasion


Echogenic abnormalities
Ant. displacement and enlargement of SV

45. PSA DRE TRUS
 Sensitivity 96% 87% 84%
 Specificity 14% 60% 41%67%
 PPV 32% 48% 52%
 NPV 88% 92% 91%

46. CT scan
• Primary role
–Size determination of the gland
– Assess pelvic LN metastasis
– Treatment planning
– Extra Prostatic Extension:
• Loss of periprostatic fat planes
• Bladder base deformity
• Obliteration of the normal angle b/w the SV and post. aspect of UB
• LN involvement
– Abnormality in size
– Sensitivity 25%
– Reserved for patients with higher PSA values (>20-25 ng/ml)
– CT guided FNAC

47. MRI
• Superior to CT in defining prostate apex, NVB and anterior
rectal wall
• Better delineation of periprostatic fat involvement
• Indication
Abnormal DRE
PSA>20
Poorly differentiated ca
Sensitivity to locate gland tumor- 79% and specificity- 55%
LN detection- Low sensitivity but high specificity
MRSI (Magnetic Resonance Spectroscopic Imaging) : increases
accuracy

48. 99TC BONE SCAN
• Clinically apparent metastatic disease limited to bone in 80-
85% of patients of metastatic ca prostate
• A close correlation exists between pretreatment PSA level
and incidence of abnormal bone scan results
• Osteoblastic secondaries
•MC sites of metastasis
Vertebral column 74%
Ribs 70%
Pelvis 60%
Femora 44%
Shoulder girdle41%

49. Thank you
• To be continued