In prostate cancer, the word “chemotherapy” is essentially synonymous with Taxotere (docetaxel). Taxotere is by far the most common chemotherapy medicine for prostate cancer. Taxotere is an active agent that is also employed for the treatment of breast cancer and lung cancer. Jevtana, which has many similarities to Taxotere, more than any differences, is the second most commonly used type of chemotherapy. Taxotere (and Jevtana) are administered intravenously every three weeks in a cyclical fashion.
These agents are typically used to treat
advanced metastatic prostate cancer. Men with preexisting bone pain usually
notice significant improvement within a week or two of starting therapy. Another sign that the Taxotere is working is
PSA levels decline. If the PSA
does not decline immediately, Taxotere should still be continued for at least
two or three cycles before concluding the treatment is not working. An initial
increase in PSA for 30-60 days is not an indication to stop Taxotere because on
occasion men have a bump upward in the PSA, a “flare” from the dying cancer
cells. However, if the PSA continues to
rise after three cycles, it indicates that the Taxotere is not working.
Cancer response rates can be further improved
by using Taxotere in combination with Carboplatin. Carboplatin is also administered
intravenously and can be conveniently administered at the same time as the
Taxotere. In patients who have normally functioning bone marrow and normal
kidney function, a small dose of Carboplatin, say 200 mg, can be safely
administered along with full-dose Taxotere.
Carboplatin is well-tolerated though occasional side effects include
low-grade nausea, numbness in the hands or feet and tiredness.
Taxotere administered in combination is with
Avastin and Revlimid is another very active combination that will induce a
cancer response in most men. Avastin, which is FDA-approved for colon cancer
but not prostate cancer, is an angiogenesis inhibitor given intravenously every
two weeks. It is generally well-tolerated but requires concomitant blood
thinners due to a higher risk of blood clots. Avastin can also cause slow wound
healing and can't be used before or after surgery. Revlimid oral agent that is FDA-approved
for a type of bone cancer called myeloma. Like Avastin, it also functions by
blocking new blood vessel growth. When using Revlimid in combination with
Taxotere and Avastin we typically limit the Revlimid dosage to 5 mg daily. Side effects
at this dose range are rare though occasionally platelet counts can be
suppressed.
A study using these three agents in
combination that showed very high response rates was published by Dr. Figg from
the National Cancer Institute. This same
study also reported a high frequency of fairly notable side effects including
numbness of the hands and feet as well occasional cases of jaw damage, a
condition called osteonecrosis. Despite
these significant problem, Dr. Figg reported that the vast majority of the men
achieved significant remissions and that the remissions tended to be quite long
lasting.
Aggressive combination protocols like these
require various supportive measures to be successful. Defending against low white blood cell counts
with an immune stimulator such as Neulasta should be considered routine. Neulasta
is a powerful medicine that stimulates the bone marrow to manufacture white
blood cells more quickly and in greater numbers. Side effects are rare but
occasionally, serious but transient episodes of lower back pain can occur.
Another bone marrow stimulator, Aranesp, can
defend against the development of progressive anemia. Anemia is a common in men
with prostate cancer and can be due to hormone therapy, chemotherapy, or even
from the prostate cancer invading the bone marrow. Symptoms of anemia are
shortness of breath and fatigue. Timely and appropriate use of Aranesp helps to
maintain normal red blood cell counts and can reduce the need for blood
transfusions.
Taxotere usage has been greatly postponed in
men with metastatic prostate cancer ever since the FDA approval of Xtandi and
Zytiga. These agents induce meaningful remissions with far fewer side effect
than Taxotere. However, patient tend to
have a rapid and virulent progression of the cancer after Zytiga and Xtandi
stop working. Taxotere, possibly in
combination with Carboplatin should probably be implemented quickly in most
cases.
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