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Urologic Advances
The field of urology continues to make extraordinary advances in knowledge,
skills, technology and healthcare delivery. These advances have in some cases
required urologists to make attitude changes in the way we manage our
patients. In this issue I will attempt to update the current diagnoses and treatment
options for the common urology problems.
The Urology Institute celebrated its 10th Anniversary in August of 2002 at
the MGM Resort in Las Vegas. In this issue Dr. Green shares a few photos of
the trip, which included meetings, entertainment and a banquet.
Dr. Rufus Green is a Board Certified Urologist and Chief of Urology at the
St. Paul University Medical Center, and
a member of the Clinical Teaching Staff
at The University of Texas Southwestern
University School of Medicine in
Dallas, Texas. Dr. Green and his wife
Bernadette have three children, Geoffrey
Alan, Rylee Dominique and Remington
Rufus.
Doctor Green answers some important questions updating current trends in Urology.
Let us begin.
PROSTATE CANCER
Q: What can I do to reduce my risk of developing prostate cancer?
A: There is evidence to suggest that the intake of red meat and dairy
products appears to be related to increased risk of metastatic prostate cancer.
A low fat, high-fiber, plant-based diet slows PSA progression. In addition, there
is a positive association between moderate alcohol (liquor, not wine or beer).
There is no association proof that exercise prevents/reduces the risk of developing prostate cancer.
Q: Is the PSA test still valid for prostate screening?
A: Although highly specific, the sensitivity of PSA in detecting prostate
cancer has room for improvement. Multiple forms of PSA have been developed to
increase the sensitivity and thus the detection rates for prostate cancer. Use
of free PSA increases the detection rate of aggressive prostate cancer more than
PSA alone.
Q: How many needle biopsies of the prostate should be done to detect prostate
cancer?
A: The standard number of biopsies is 6-8; however, more biopsies do
detect more organ-confined prostate cancer. When the standard 6-8 biopsies do
not detect prostate cancer in the face of an elevated PSA, then (extreme/saturation
biopsies) 18-20 should be done under local anesthesia.
Q: What are the treatment options for prostate cancer?
A: The treatment choice takes into account the patient's age, overall
health, grade, stage, and Gleason score of the prostate cancer. In general for
organ-confined cancer the choices are expectant, surgery, radiation (external)/(internal)(brachytherapy), hormonal and cryotherapy. Each modality has advantages and
disadvantages. Outcomes for surgery and brachytherapy are similar for low stage
and grade disease. Cryotherapy has primarily been reserved for radiation failures.
Hormonal therapy has primarily been used for advanced disease or as adjuvant
therapy.
KIDNEY STONES
Due to advances in shockwave lithotripsy and endoscopic instrumentation, the
majority of urinary stones can now be managed without open surgery. This results
in improved overall efficiency with decreased loss of service for patients.
Q: How do lithotriptors break kidney stones?
A: A number of mechanisms have been proposed to explain how
shockwaves (SW) break kidney stones, namely, 1. Spall, in which the compressive
component of the shockwave reflects off the stone and the stone fails in tension;
2. Cavitation, in which the tensile component of the shockwave induces bubbles
that collapse violently and pit the stone surface; 3. Squeezing, in which, as
the shockwave propagates through and past the stone, differential stress between
the stone and fluid causes the stone to bulge and fail; 4. Superfocussing, in
which reflection of the SW off curved surfaces or corners of the stone produces
localized regions of high stress; 5. Fatigue, where exposure to successive SWs
acts to progressively widen existing flaws until the stone fails; and 6. Layer separation,
where failure in tension occurs at internal sites of weakness.
It is most likely that all of these mechanisms contribute to stone fragmentation.
Q: How do you diagnose kidney stones?
A: Certainly the symptoms of flank pain, nausea, hematuria
with or without fever, UTI, or frank vomiting are highly suggestive of kidney
stones; however, radiologic imaging confirms the diagnosis. Helical CT is emerging
as the preferred modality for definitive diagnosis of renal calculi. CT has
been shown to have superior sensitivity and specificity when compared to intravenous
urography.
FEMALE UROLOGY
Urinary incontinence affects approximately 20 million individuals in this country.
Unfortunately, many Americans do not seek treatment due to embarrassment and
lack of understanding of the condition.
Q: Are there different types of urinary incontinence?
A: Yes: total incontinence, urge incontinence, stress incontinence,
overflow incontinence and transient incontinence. It is very important to identify
the type of incontinence so that the appropriate treatment can be selected.
Urodynamic testing can help identify the type of incontinence.
Q: What is female sexual dysfunction (FSD)?
A: Female sexual dysfunction is characterized as a disturbance
in, or pain during, the sexual response cycle. FSD is actually more common than
male sexual dysfunction. FSD is a widespread problem, affecting 25% to 63% of
women in the U.S.
Q: Are kidney stones common in pregnancy and how do you manage them?
A: It has been estimated that kidney stones occur in one in
1500 pregnancies. Most stones are diagnosed during the second and third trimesters
of pregnancy. Most of these stones will pass (70%), therefore, conservative
therapy should be the initial approach. If initial conservative therapy fails,
then intervention is required. The most common type of intervention is ureteral
stent or percutaneous nephrostomy tube placement. In few cases ureteroscopy
with stone removal is done. In all cases x-ray exposure should be minimized.
Shockwave lithotripsy has not been approved for use in pregnancy. The imaging
modality of choice is ultrasound.
KIDNEY DISEASES
Kidney cancer occurs in approximately
30,000 Americans per year.
Approximately 12,000 of these individuals will die this year. Survival rates
are good (95%) when detected early and surgically removed. Those with advanced
kidney cancer have a 20% two-year survival.
Q: Are there less radical ways of treating kidney cancer than removing
the entire kidney?
A: Radical nephrectomy is still the gold standard for managing
kidney cancer. However, small kidney cancers may lend themselves to newer treatment
modalities (nephron-sparing) surgery such as partial nephrectomy or ablative
surgery done open or laparoscopic.
Q: What is a UPJ obstruction?
A: A UPJ obstruction is a narrowing at the junction of the
ureter and kidney. Most common etiology is congenital. Common symptoms are intermittent
flank or abdominal pain. May also be associated with hematuria and urinary tract
infection. Management of UPJ obstruction depends upon the presence of symptoms,
deteriorating renal function, presence of stones or infection. Open surgery
has been the standard; however, less invasive endourologic and laparoscopic
approaches are available.
BPH (THE ENLARGED PROSTATE)
Enlargement of the prostate is a normal consequence of ageing. As the population
ages, more men are presenting with symptoms of BPH. Transurethral Resection
of the Prostate (TURP) is the gold standard for treating BPH.
Q: What are some of the newer modalities for treating BPH?
A: Pharmacotherapy has become the first line of treatment, although
the long-term outcomes are not fully known; this modality fails to reach satisfactory
outcome indicators as often as TURP. Thermotherapy uses heat to destroy prostate
tissue. Examples of thermotherapy are Transurethral Microwave Thermotherapy
(TUMT), Transurethral Needle Ablation (TUNA) and Water-Induced Thermotherapy
(WIT). Overall the results with these alternative therapies vary from 50-80%
of results achieved with TURP.
MALE INFERTILITY
In approximately 50% of infertility cases the male is responsible. Approximately
15% of couples are unable to achieve pregnancy without some form of assistance.
Q: What are some surgically treatable causes of male infertility?
A: Varicoceles are the most common treatable cause of male
infertility. After repair of a varicocele 30-40% of couples achieve pregnancy;
50-80% show improved semen. Other treatable causes are infections, hydroceles,
spermatoceles, epididymal cysts, and sperm granulomas.
Q: What are the current pregnancy rates of vasectomy reversal?
A: If the reversal is performed within three years of vasectomy,
98% potency with sperm and 74% pregnancy rate. However, if vasectomy was performed
more than 15 years,, 71% had sperm with 30% pregnancy.
Q: If a man has no sperm (azoospermia) what are the alternatives for
obtaining sperms?
A: There are a number of sperm retrieval techniques, namely,
Open Testis Biopsy (TESE), Microsurgical Epididymal Sperm Aspiration (MESA),
Percutaneous Epididymal Sperm Aspiration (PESA), Vasal Aspiration of Sperm (VAS),
Seminal Vesicle Aspiration (SVA).
Q: Are there genetic risks in azoospermic men undergoing sperm retrieval
techniques for use in assisted reproductive techniques?
A: Yes, men who have congenital absence of the vas may carry
a cystic fibrosis gene mutation. Severe oligospermia may have a deletion in
their Y chromosome that is responsible for low sperm production. This may be
passed on to male offspring. The most common karyotypic abnormality found in
men with azoospermia and severe oligospermia is 46XXY (Klinefelter's Syndrome).
PEDIATRIC UROLOGY
Common problems in pediatric urology revolve around the following areas:
Antenatal Hydronephrosis, Neonatal Urology, Infancy and Childhood Urology, and
Infection, Bedwetting, and Reflux.
Q: What are the most important prognostic features in antenatal hydronephrosis?
A: Oligohydramnios is associated with pulmonary hypoplasia
and poor renal function and/or severe obstruction.
Q: What are the indications for interventions?
A: Bilateral hydronephrosis, thick bladder wall (male),
and oligohydramnios; favorable urine parameters, normal karyotype, and no other
severe congenital structural anomalies.
Q: What are the most likely causes of antenatal hydronephrosis?
A: UPJ Obstruction (41%), UVI Obstruction (23%), duplication
anomalies (13%), Posterior urethral valves (10%), Others (13%) and Reflux (15-20%).
When confronted with an abdominal mass in a child, think Urology.
Q: What are the fertility issues associated with undescended testes?
A: Normal descended testes have a 95% fertility rate, unilateral
undescended testes 71-92% , and bilateral undescended testes 43-62%.
Q: What is testis torsion and can testis torsion be present at birth?
A: Testis torsion is the twisting of the testis in the scrotum,
resulting in complete or partial blockage of blood flow to the testes. Testis
torsion in the Neonate occurs in the third trimester and presents at birth with
a firm, swollen, erythematous scrotum or absent testis. The testis is not salvageable
and can be removed non-emergent. Childhood torsion is an emergency. Salvage
rates decrease dramatically beyond 8 hours.
Q: How do you manage pediatric urologic trauma?
A: Pediatric urologic trauma is managed similar to adults.
Primary management is observation.
MALE SEXUAL DYSFUNCTION
The term sexual dysfunction may be used by some as a synonym for erectile dysfunction
(ED), but sexual dysfunction may include a wider variety of disorders, including
diminished libido or loss of desire, premature ejaculation, inability to achieve
orgasm, and priapism.
Q: What is the most common male sexual dysfunction?
A: Premature ejaculation.
Q: What are the current drug treatment options of premature ejaculation?
A: Antidepressants, (e.g., paraxetine, sertraline, fluoxetine
and clomipramine), topical ointments, (e.g., SS-cream or lidocane), PDE5 inhibitors.
SS-cream is a newly developed topical agent made from the extracts of nine natural
products which is applied to the glans penis one hour before sex.
Q: What drugs cause ED?
A: Antihypertensives, vasodilators, cardiac drugs, tricyclic
antidepressants, and selective serotonin reuptake inhibitors (SSRIs).
Q: What oral therapies are effective for treating ED presently?
A: PDE5 inhibitor Sildenafil (Viagra). In Europe sublingual
apomorphine (Ixense), which acts centrally. Other PDE5 inhibitors are presently
being investigated.
Q: How do you treat low libido (hypogonadism)?
A: Low testosterone levels are often associated with low libido.
Men with low testosterone levels should receive replacement therapy. The side
effects of testosterone include elevation in the serum hematocrit, LFTs, lipids
and PSA. Testosterone may be administered by pill, topical gel, patches, and
injections. The gel preparation is the most common and most expensive preparation.
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