Management of Cancer of the
Head and Neck
Chemotherapy:
General Guidelines
Chemotherapy has been used in head and neck cancer in
a variety of settings. It has been used as initial "neo-adjuvant" therapy
prior to radiation therapy when organ preservation is a goal. It has been
used concurrently with radiation therapy in locally advanced tumors where
it has been shown to improve local control and decrease the risk of distant
recurrence. It has been used after definitive surgery and radiation as an "adjuvant" therapy
in patients felt to be at high risk for recurrence, and it has been used
as palliative therapy in patients with advanced unresectable or metastatic
disease.
Most chemotherapeutic agents have been investigated in head and neck cancers.
To date, the agents found to be most effective include cisplatinum, carboplatinum,
taxanes, 5-fluorouracil, methotrexate, and ifosphamide. These agents have
been used alone or in combination in a variety or regimens. The agents
vary in their single agent response rate and toxicity.
Initial evaluation of the patient by the medical oncologist requires a
detailed history and physical examination, as well as consultation with
the head and
neck surgeon and radiation oncologist to optimize care for the individual
patient. In addition to assessing the stage and extent of the cancer
via physical exam and appropriate radiographic studies, the medical oncologist
must evaluate the overall health of the patient with attention to performance
status, organ function and co-morbid conditions which might affect the
ability to use some chemotherapeutic agents. Careful nutritional assessment
prior
to therapy is essential.
Once the patient has been assessed by the multidisciplinary team, a treatment
plan is outlined. If organ preservation is one of the goals of treatment,
chemotherapy given prior to radiation therapy has been shown to be
useful in selecting those patients who are more likely to benefit from radiation
and, thus, achieve organ preservation. More recently it has been shown
that chemotherapy given with radiation can improve the chances for
local
control
of cancer and decrease the risk of distant metastases. The optimal
chemotherapy combination for either of these situations has not yet been
defined and
this is an area of very active clinical investigation. In general,
patients who
have resectable cancers but desire organ preservation should be enrolled
in clinical trials if they are available.
In the setting of advanced, unresectable cancers, recurrent or metastatic
cancer, chemotherapy is often used for palliation. Most single agents
produce objective tumor response rates of 15-35%. Combination chemotherapy
regimens
have produced higher response rates but no clear benefit in terms
of patient survival. The medical oncologist must assess the performance
status of
the patient, and his or her previous treatment prior to recommending
a specific
agent or combination.
Side effects from chemotherapy may be acute or long term. Common
side effects include fatigue, myelosuppression with risk of infection,
nausea
and hair
loss. Cisplatinum can cause renal failure and ototoxicity. The
platinum analogs and taxanes can have neurotoxicity including paresthesias
and painful peripheral
neuropathy. Some agents have mucosal toxicity, which can be worse
when they are given with or after radiation therapy. Mucosal toxicity
is
common with
5-fluorouracil and methotrexate and can also be seen with taxanes.
Medical oncologist must be aware of these and other less common
problems
when
evaluating and treating patients with head and neck cancers.
Due to the location of their tumors and the mucosal effects of
therapy, many patients with head and neck cancer are nutritionally
compromised.
If highly
toxic therapy is planned, placement of a PEG tube prior to starting
therapy enables patients to maintain nutrition during therapy
and recover more
quickly. Whether or not a PEG is in place, the patient's intake
and nutritional status
should be assessed on a regular basis during therapy with appropriate
intervention in a timely fashion.
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