Carcinoma of the prostate
Cap
Incidence and epidemiology
One of the most common cancer in the world,
several
risk factors
have been identified,
-increasing age ,
-race ( more common in black),
-positive family history of cap,
-high dietary fat intake, &
-smoking.
*PIN (prostatic intraepithelial neoplasia) is a
precursor for cap.
*Usually the tumor is multifocal within the prostate
with some variation in tumor grade.
Grading
Gleason grading system most commonly used,
it relies upon the glandular architecture.
There are 5 grades from well differentiated to
undifferentiated glandular achitecture
Gleason score by summation of the primary &
secondary areas so its from 2 to 10 grades
Staging
: (TNM staging system)
Tis-carcinoma in situ (PIN)
T1-discovered accidentally either by resected prostate
or high PSA level.
-T1a- less than 5% of resected tissue,
-T1b- more than 5% of resected tissue,
-T1c- detected by elevated PSA
T2-tumor palpable by DRE or visible by TRUS
confined to prostate.
T2a- confined to one lobe
T2b- to b
oth lobes
T3-extracapsular extension including seminal vesicle.
T4-tumor extend to bladder neck, rectum, or pelvic
side wall.
N = Regional lymph node.
N0—no regional LN.
N1—metastases to regional lymph node.
M =distant metastases.
M1a—distant metastases to non regional LN
M1b—distant metastases to bone.
M2—distant metastases to other sites.
Clinical features
*Most cases are asymptomatic
-the presence of symptom suggest locally advance
or metastatic disease.
*Obstructive or irritative voiding symptoms
if tumor grow into the urethra or trigone.
*metastatic disease to the bone or spinal cord may
cause bone pain pathologic fracture or spinal cord
compression.
*DRE may detect induration.
D.Dx of prostatic nodule include.
1-Chronic granulomatous prostatitis,
2-previous TURP or needle biopsy,
3-prostatic calculus.
*locally advance disease with lymphadenopathy may
lead to lymphedema of lower limb.
Investigation
*Uremia, if pt had obstructive uropathy.
*Anemia, may be present in metastatic disease.
*Tumor markers Alkaline phosphatase & serum acid
phosphatase may be elevated,
-
PSA
(prostate specific antigen) has great rule in
diagnoses of cap
D.DX of high PAS
1-BPH
2-urethral instrumentation
3-infection
4-vigorous massage
4-prostatic biopsy or TURP
But the elevation not as high as in cap.
*normal value depend on age usually <4 ng/ml.
*PSA need about one month to return to its normal
value after prostatic biopsy or TURP and only one
week after prostatic message
*Imaging. Like
-TRUS (transrectal ultrasound),
-endorectal MRI, &
-bone scan
(cap typically give osteoblastic lesion in bone).
*Prostatic biopsy
Usually obtained under TRUS guidance.
Indicated in pt with either abnormal DRE or elevated
PSA.
Treatment
The treatment depend on
-the grade & stage of the tumor,
-the life expectancy of the pt,
-associated morbidity,
-the ability of therapy to ensure disease free survival,
-the pt & physician preference.
A-Localized disease
1-Radical prostatectomy
. Result depend on tumor
stage &selection of better candidate pt usually with
organ confined tumor.
2-Radiation therapy& brachytherapy
. improved
imaging & the use of 3-dimention can increase the
dose & decrease the toxicity to the surrounding
normal organs.
3-Cryosurgery.
Freezing of the prostate by using
multiprobe cryosurgical device. Temperature may
reach -25 to-50 C lead to tissue destruction.
The term
brachytherapy
refers to a treatment
technique that places radioactive sources in close
proximity to or directl into the tumor.
-can be classified as either interstitial or intracavity.
*
Interstitial brachytherapy
involves the placement
of radioactive needles, afterloaded needles or
catheters, or radioactive seeds directly into the
prostate,
bladder, penis, or periurethral soft tissues.
*
Intracavitary brachytherapy
includes placement
of radioactive catheters into a lumen or orifice, such
as in the urethra, to treat urethral and penile tumors.
*Permanent implants involve the use of radioactive
seeds that are left in the patient.
B-Metastatic disease.
a single microscopic metastatic focus of prostate
cancer in only one pelvic lymph nodes is a hallmark
that its incurable by any currently available treatment
madality
Usually treated by endocrine therapy, because cap is
hormonal dependant tumor about 70-80% of pt with
metastatic cap responding to androgen deprivation.
Complete deandrogenization is regarded as gold
standard procedure need blockage of both testicular &
adrenal androgen.
Testiculat androgen
(95% of testosteron)
can be blocked by either
Surgical
through bilateral orcheactomy or
Medical
by LHRH analogue which cause increase
testosterone release in the first few weeks so should
covered by flutamide to overcome flare up specially
if there is spinal cord metastasis
Andral androgen
blocked by drug acting on the
peripheral receptors like flutamide