Bladder
Cancer Newer TreatmentsCarcinoma in situ: For early bladder
cancer (carcinoma in situ lesions) treatment with a solution containing a live
anti-tuberculous vaccine (called BCG) leads to superior survival figures. This is done through a bladder catheter and is called
"intravesical therapy with BCG" or "BCG treatment" for short.
This local therapy for superficial bladder cancer is apparently superior to intravesical
chemotherapy (Ref. 4). However, phase III trials are needed to establish, which
dosage schedule gives the largest survival advantage. Radical
transurethral resection of the prostate (TURP): It seems that superficial
disease (Tis and T1 stage) and also T2 (which invades the muscle) can be handled
with radical TURP. There was no 10-year survival advantage for a group of patients
who had a radical cystectomy (=cutting the bladder out) initially (see Ref. 5).This
author, when reviewing the data of the Memorial Sloan-Kettering Cancer Centre
in New York, found that the group with initial radical cystectomy had a 10-year
cancer survival rate of 71%, whereas the radical TURP group had an overall cancer
survival rate of 76%. The key in this study is that the patients had initially
3-monthly and then 6-monthly follow-up examinations where they were scrutinized
for recurrences. If a recurrence was found, then immediate action was taken to
deal with this. Re-resection or radical cystectomy was now done and the surgical
specimens were then pathologically examined. Now the bladder cancers were restaged
pathologically, which is much more accurate than clinical staging, and the appropriate
treatment was given. 34% of the initial TURP group had a recurrence and were then
restaged. Their 10-year survival with stage T0 ( no more tumor found) was 82%,
whereas for patients with restaged T1 bladder cancer it was 57% (Ref.5). This
is a superb longterm result for bladder cancer! Radiation seems to be used mostly in combination
with some other treatment modality. Even though it has good effects on its own
in terms of reducing bulk of the disease and in treating pelvic lymph nodes and
paraaortic lymp nodes, it is even more effective when combined with surgery or
chemotherapy. Some groups do presurgical radiation and remove the remaining
cancer tissue 4 weeks after radiation. Other groups prefer to do surgery and then
radiate after that to treat possible local cancer spread and/or pelvic and paraaortic
lymph nodes that could not be removed technically. The patient needs to be informed
why a certain combination would be more advantantageous in a certain situation
than the other. The key is to individualize and do what is best for the patient. Combination
chemotherapy has been found to be much more effective in delaying tumor
growth than any single chemotherapeutic agent. However,
even though short term responses can be obtained in 30 to 50 % of patients, the
longterm survival has only marginally improved. Ref. 6 explains that attempts
concentrate presently on improving the survival rates by stimulating the immune
system with granulocyte colony stimulating factor (colony-forming unit factor
or CFU-C factor) and other immune stimulants in order to be able to treat with
higher doses of combination chemotherapy. This has already been very successful
with testicular cancer in improving survival rates. However, bladder cancer is
a type of cancer that is inherently more resisitant to both radiation and chemotherapy.
The authors in Ref.7 have shown that even with "incurable" stage 4 bladder
cancer patients it is possible to achieve survivals at 5-years with an aggressive
protocol. Using a combination chemotherapy with trexall (=methotrexate), vinblastine,
doxorubicin, and cisplatin (M-VAC) these urological oncologists from New York
were able to cure 41% of these patients with chemotherapy alone. 33% of patients
survived 5 years by treating with this combination regimen first and subsequently
removing the remaining cancer tissue surgically. They also found that the better
5-year survival rates were obtained in those patients who had localized, but non
operable primary tumors initially or who had metastases restricted to lymph node
sites rather than those patients who had distant metastases. Biological
therapies: There is a tendency lately to explore less toxic modalities
of treatment. However, one has to remain critical of the effectiveness (called
"efficacy") of these treatments. On the other hand the researchers are
very much aware that many of the present therapies known to improve survival have
been labeled in the past as "hoax therapies". I would like to summarize
some of the steps that could be taken right now:
| What we can do
now re. prevention of bladder cancer |
Any smoker can quit smoking. This is a proven cancer preventing
step. Also anybody who is presently inhaling second hand smoke should lobby for
a smoke free work environment. Some jurisdictions have this law in place and
the majority of people like it. People can change their diet.
If a person eats more vegetables and less refined carbohydrates, the amount of
natural anti-cancer substances in the food intake are increased and the negative
effect on the cyclic AMP from hyperinsulinism is removed. This zone-type diet
will lead to a much stronger immune system, which will prevent or reduce the development
of many cancers (Ref.8). Chromosomal abnormalities
that have been found in many bladder cancers tend to lead to a higher resistance
to treatment as the cells are deficient for the normal cell functions. In order
to get a lasting break-through for the patients who do not respond to the presently
known treatment modalities, newer methods such as monoclonal antibodies attached
to the patient's own activated macrophages or genetic vaccines etc.will have to
be employed. Several Cancer Agencies around the world are investigating these
methods, but nothing concrete, which would stand up to the test of prolonging
long-term survival has yet been found. Watch out though as it is there that break
throughs will come from. |
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