الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
- Bladder carcinoma is the most common encologic
problem in Egypt. Two different clinicopathological
entities are generally recognized. namely:
bilharzial and non - bilharzial types. The former
type
iasis
which is
is more
associated with urinary schistosomcommon
and affects farmers at a
relatively young age.
Transitional cell carcinoma of the bladder
’usually presents as localized superficial lesion
in approximately 80 o of the cases. However •
after initial management the recurrence rate
ranges from’ 40 to 70 per cent. Several intravesical
chemotherapeutic agents have been used
either as a prophylactic or in the treatment of
completely unresected tumor. More
chemotherapedtic agents have been
after transurethral resection and
recently •
used immediately
fulguration to
prevent implant&~ion of the tumor which may be
responsible for recurrences.
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Several clinical trials using new drugs have
justified the increasing incorporation of intravesical
chemotherapy into therapeutic programs for
bladder cancer patients. Until recently, thio-tepa
and ethoglucid were the only agents used and they
were largely reserved for patients unsuitable for
surgery •
Treatment patterns are gradually changing on
two levels. New agents such as mitomycin C and
adriamycin have been introd~ced. These d rug s
appear to produce higher objective response rates
than thio - tepa with less toxicity. Although a
prospective randomized study has yet to prove
their superiority the excellent response rat e s
achieved in patients failing thio - tepa therapy
and the impressive complete and partial regression
rates documented by several investigators suggest
this advantage.
Instillation of antitumor agents into the
bladder within 48 hours of complete endoscopic
excision of superficial tumors has been shown to
- 111 -
lengthen the tumor - free interval and reduce the
recurrence rate. Although myelosuppression continues
to be a therapy associated with risk when
cytotoxic agents are instilled shortly after surgery
, the degree of this effect seems to b e
correlated with the molecular weight of the agent.
It is hoped that this potential hazard will b e
diminished or completely eliminated with the use
of drugs that have s, higher molecular weight than
thio - tepa.
The relative risks of local and systemic
side effects, for each drug need to be· determined.
Information must be gained on each drug’s
ability to enter normal or neoplastic urothelial
cells. The role of urinary pH, bladder capacity
and vesico-ureteric reflux must all be correlated
with toxicity and response rates for each
drug. The duration of treatment has been largely
empirical and limited to 1 to 2 hr••:.varying
this time may be fruitful. The frequency 0 f
instillation has also varied , however, m 0 s t
regimens rely on a weekly schedule. More frequent
instillations might be more effective. The role
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of continuous bladder irrigation has
explored. A low drug concentration
contact with the urothelium might
ior effect.
not been
in prolonged
provide superx:
few agents , such as cisplatin and methotrexate
, have been found consistently to induce
clin-ically useful remission and a 9 - 12 months.
Prolongation of life for responders compared to
non - res~onders. Since cisplatin, methotrexate ,
adriamycin and probably mitomycin C have been
shown to be effective anti-tumor agents for
transitional cell carcinoma , patients with disseminated
bladder cancer can now be considered
for chemotherapy, where clinically appropriate.
The a~m of immunotherapy is to stimulate
the immune ~atem to eliminate an established
tumor , prevent a recurrence • and prevent the
development of a new tumor. Unfortunately, we
still cannot predict with certadnty the effects
of specific immunization in an individual patient
with tumor. Both humoral and cellular immunity
may be stimulated by a particular regimen and
lead to enhancement of tumor growth by blocking
antibodies rather than tumor destruction b y
cytotoxicity and production of deblocking antibodies
rather than blocking antibodies.
”