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PENILE CANCER
Urologists at the University of Chicago specialize
in the latest surgical techniques to treat penile
cancer. In combination with colleagues in Medical
Oncology and the Cancer Research Center, we offer
a comprehensive and diverse option of therapies.
Diagnosis
Penile cancer is rare in the United States (annual
incidence of 1-2 per 100,000 men, which translates
into 1400 cases yearly). Squamous cell carcinoma
accounts for 95% of penile cancer cases. The highest
incidence in the world is in South America, India,
and Africa. Penile cancer is most common in uncircumcised
and nonwhite populations. Onset is in the fourth
and fifth decades of life.
The cause of penile cancer appears
to be chronic irritation. Predisposing factors
include presence the foreskin (uncircumcised men),
phimosis (tight opening of the foreskin), and
poor hygiene. Phimosis is present in more than
50% of patients with penile cancer. The closed
space under the foreskin allows accumulation of
smegma and chronic irritation. The risk of penile
cancer can be virtually eliminated by neonatal
circumcision. Delayed circumcision offers only
slight protection against the subsequent development
of penile carcinoma. Penile cancer is associated
with exposure to ultraviolet [UV] radiation treatment
for psoriasis. There is also evidence of a relationship
between penile cancer and HPV types 16, 18, and
33. These are commonly found in women with cervical
cancer.
Penile cancer begins as a small
lesion and gradually enlarges to involve the entire
penis. It may be flat and cause an ulcer. Alternatively,
it may extend away from the penis with the appearance
of cauliflower or broccoli. Laboratory studies
are usually normal in patients with penile cancer.
There is a limited role for radiologic imaging.
CT and MRI scans can be helpful in patients with
high grade or invasive tumors in whom pelvic or
retroperitoneal lymphadenopathy is suspected.
A delay in seeking medical attention is very common
and can result in progression to advanced local
disease. The course of penile cancer is relentless
and most untreated patients die within 2 years.
Penile cancer metastasizes in
a predictable pattern to inguinal lymph nodes
followed by drainage into pelvic lymph nodes (and
beyond). Metastatic deposits in the regional lymph
nodes continue to enlarge if left untreated, causing
skin necrosis, infections, and erosion of the
femoral vessels. The risk of spread (metastasis)
is related to the size of the initial (primary)
lesion. Spread is most common to the lymph nodes,
especially those in the thigh. The tumor begins
as an area of induration (firmness), erythema
(redness), warty growth, nodule, or superficial
ulceration. Rarely painful, constitutional symptoms
(fatigue, fever, etc.) may result from chronic
infection in the nodes.
At clinical presentation, determination
should be made of the lesion’s size, location,
and depth of involvement. The scrotum and perineum
must be inspected and inguinal areas palpated.
Pathologic staging by deep biopsy remains necessary
to plan appropriate management. Accurate staging
is imperative for guiding treatment recommendations.
If there are suspicious (enlarged and hard) lymph
nodes in the groin, antibiotics are often prescribed.
If the lymph node enlargement does not disappear,
then surgery may be required to remove the lymph
nodes (ilioinguinal lymphadenectomy).
The goal of treatment is complete removal of the
primary lesion with adequate margins. The standard
of therapy for the primary lesion is partial or
total penectomy (total or partial removal of the
penis). Partial penectomy has produced the lowest
recurrence rate and is the standard against which
all other treatment modalities must be compared.
Because of the disfigurement and psychological
impact of penile amputation, other treatment options
have gained increasing acceptance in the treatment
of penile cancer, but must be used within their
limitations.
- Circumcision:
20% percent of lesions are located on the prepuce.
If the cancer is small, low grade, noninvasive,
involves only the prepuce, is not located near
the coronal sulcus, and permits an adequate
margin, complete tumor removal can be accomplished
with circumcision, although circumcision alone
is followed by a 30 -50% recurrence rate. Long
term survival approaches 90%. These patients
must be followed very closely.
- Moh’s
Microsurgery (MSS): A method of surgically
removing skin cancer by removing tissue in thin
layers. Zinc chloride paste, a fixative, is
applied after application of dichloroacetic
acid, a keratolytic agent. Layers of chemically
fixed tissue are excised and examined microscopically
until cancer free planes are obtained. MSS includes
color coding of excised specimens, accurate
orientation through creation of tissue maps,
and frozen section analysis of excised tissues.
The micrographic surgeon is responsible for
all steps in the process, including interpretation
of frozen sections. Healing is by secondary
intention. Best applied for small distal penile
lesions less than 1 cm. Following Moh’s
surgery, the glans is often misshapen and meatal
stenosis is common.
- Laser:
Nd-YAG; acceptable for the rare superficial
Tis, Ta, and T1 lesions (survival compares favorably
with partial penectomy). Although laser therapy
offers the advantage of being organ preserving,
the depth of laser penetration and histologic
confirmation of tumor destruction can be difficult
to determine; deep biopsies are necessary.
- Penectomy:
For lesions near the coronal sulcus or involving
the glans and distal shaft of the penis, partial
penectomy is necessary. A 2 cm margin proximal
to the tumor is desirable, leaving a 3 cm or
greater stump. The stump must be adequate for
upright urination, a directable urinary stream,
and satisfactory sexual function. Negative margins
must be confirmed in the operating room. Local
recurrence rates are 0-6%.
Larger lesions, or those in the mid or proximal
shaft of the penis, require a radical (total)
penectomy. This is also true for those lesions
that may be treated with a partial penectomy
but will, if performed, result in a stump inadequate
for upright urination, a directable urinary
stream, and satisfactory sexual function.
- Radiation
Therapy: The sole advantage of radiation
therapy is that it preserves penile anatomic
structure. The disadvantages are that penile
cancers are relatively radioresistant and there
is a high rate of complications (fistula, stricture,
edema, superficial necrosis, and pain). Approximately
30-50% patients will require subsequent penectomy.
- Chemotherapy:
There is no defined role for chemotherapy, although
it may be of help in patients with palpable,
bulky, bilateral inguinal adenopathy proved
by biopsy who are at high risk for local recurrence
and distant metastasis. Chemotherapy prior to
lymph node dissection may make surgery technically
easier and may improve surgical margins. The
most effective chemotherapeutic drugs are cisplatin,
bleomycin, and methotrexate.
Treatment of penile cancer
is often individualized to each patient. Surgeons
at the University of Chicago are trained in
the most up-to-date and technologically-advanced
methods of treating kidney cancers. At you
appointment, your surgeon will be glad to
discuss all of these treatment options with
you.
Surgery is the main treatment for penile cancers.
Partial Penectomy
- This involves removal of the
end of the penis. This operation is used for
penile tumors that are small and located towards
the tip of the penis.
- A stump of penis is left
behind through which the patient urinates and
ejaculates.
- If an inadequate length of
stump is left behind, the entire penis is removed
(see Radical (Total) Penectomy, below.
- Patients are followed closely
for any sign of recurrence.
- This operation is rarely
used in conjunction with a lymph node dissection.
Radical (Total) Penectomy
- This involves removal of the
entire penis and urethra (the tube through which
urine exits the body). This operation is used
for penile tumors that are large and located
in the middle or at the base of the penis. Also,
this operation is used when a partial penectomy
is attempted but adequate length is not achieved.
- The urethra is redirected
to the area between the scrotum and rectum (perineal
urethrostomy). The patient must sit to urinate
and cannot ejaculate. The testes are left in
place so reproduction is possible, but only
through surgery to harvest sperm from the testes
followed by in vitro fertilization.
- Patients are followed closely
for any sign of recurrence.
- This operation is often used
in conjunction with a lymph node dissection.
Ilioinguinal Lymph Node Dissection
- This involves removal of
the lymph nodes in the groin. This operation
is used for men with penile cancer who have
palpable masses in their groins after taking
6 weeks of antibiotics.
- Ilioinguinal lymphadenectomy
can carry substantial morbidity, such as infection,
skin necrosis, wound breakdown, edema, and even
a low, but finite, mortality rate.
- Patients are followed closely
for any sign of recurrence.
- Because the treatment of
penile cancer is often individualized to each
patient, at your appointment, your surgeon will
be glad to discuss all of these treatment options
with you
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