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By
the International Paraneoplastic Association
Updated
May 23 2000
What
is Paraneoplastic Cerebellar Degeneration (PCD)?
A
paraneoplastic syndrome is an autoimmune disease, similar to diseases such
as Lupus, rheumatoid arthritis or psoraisis. A 'neoplasm' is a cancer,
whereas a 'paraneoplasm' is an antibody produced by a patient's own immune
system to keep cancer at bay - sort of like nature's chemotherapy. In most
cases these cancer-fighting antibodies focus their attack on the cancer
cells. A paraneoplastic syndrome occurs when a cancer victim produces antibodies
that end up attacking not only the cancer, but also healthy cells. In rare
instances the paraneoplastic antibodies attack the cerebellum, the area
of the brain located at the lower back of the head, just above the brain
stem and below the cerebral cortex. The cerebellum is responsible for all
the wonderful things we take for granted: balance, swallowing, voice volume,
fine motor coordination,
eye movement, etc. Paraneoplastic
Cerebellar Degeneration (PCD) is just one form of paraneoplastic disorder.
In
a person with PCD his/her own immune systems produce hostile antibodies
which are transported through the circulatory system. These antibodies
are found in blood plasma, but somehow make =
How
is PCD diagnosed?
In
the past, diagnosing PCD and other paraneoplastic disorders was difficult,
often involving tests on spinal fluid that was extracted through a lumbar
puncture. Today, however, a simple blood test can be performed to determine
the presence of PCD-related antibodies. One laboratory doing this blood
test is Athena Diagnostics, Inc. in Boston.
A
correct diagnosis is very important. There are other diseases and conditions
that mimic the neurological symptoms of paraneoplastic disorders and PCD
patients are often initially misdiagnosed. PCD often occurs in patients
with lung, breast, ovarian and other cancers. In some cases, the symptoms
of PCD show up before the cancer is even suspected. Prompt diagnosis of
PCD can help doctors find cancer earlier if it exists. However, it is relatively
common for people with PCD to have occult cancers --- that is, cancers
that are difficult to find or diagnosis. In some diagnosed cases of paraneoplastic
disorders, cancer is never found.
In
patients where an underlying cancer is detected, doctors usually recommend
treatment of the cancer as the first step. In some cases, PCD symptoms
and degeneration has been abated upon tumor excision, chemotherapy, or
radiation. It is therefore important to locate the source of the cancer,
if possible, and work to eradicate it.
In
addition to treatment of the primary cancer, PCD patients can also undergo
"plasmapheresis" a sort of blood dialysis in which the plasma is replaced
with saline solution or other fluid in an effort to flush out the antibodies
that are causing the harm. This blood cleansing technique can ease the
symptoms of PCD, and can sometimes arrest any progression of neurological
dysfunction so it is important that patients avail themselves of this treatment
as soon as possible. A similar treatment, IVIG, also is used to cleanse
the antibodies from the blood.
Some
patients respond to steroids such as Cortisone, Prednisone, or Prelone.
Some doctors may wish to try using a steroid-stimulating hormone called
ACTH as an alternative. There is also the possibility of treatment with
IVIG, or intravenous gamma globulin, as well as Cytoxin, a chemotherapy
drug called cyclophosphamide.
Dr. Robert Darnell at Rockefeller University in New York City also recently announced that his research laboratory has had some success in lessening the effects of certain types of PCD through the use of immunospressant drugs. This therapy is still in the experimental stage, however.
Unfortunately, research into new and effective treatments for PCD are limited. One of the goals of the International Paraneoplastic Association is to lobby for greater research and medical attention to these disorders.
How
else might we combat the neurological deficits of PCD?
Physical
therapy, speech therapy, and occupational therapy can help patients to
recover some function. Another effective technique is aquatherapy. Aquatherapy
is assisted "walking" in a pool with the help of therapists and flotation
devices. The water helps helps patients with severe ataxia to feel a greater
sense of freedom and ease of motion. Some aquatherapy centers have open
hours in which patients can use the specially equipped pool with friends
or family members who have received some basic training in appropriate
techniques.
PCD
patients are also hypercoagulopathic, meaning that their blood clots easily,
presenting a risk of pulmonary embolisms and the like. Physical therapy
important on this basis alone: regular exercise will help the patient lessen
his/her risk of blood clots by staying as active as possible; aquatherapy
can be one way to do that.
What
sort of research is being done on PCD?
Much
of the research on PCD is limited, as it is a rare disorder. The primary
concern of physicians is understandably treatment of the underlying cancer.
Many physicians hold the belief that Paraneoplastic Cerebellar Degeneration
is an untreatable sign of imminent death and therefore find it to be an
unfruitful area for research. This is an unfortunate attitude since many
PCD patients live for years after diagnosis. Also, understanding the antibodies
related to paraneoplastic syndromes might actually help us to better fight
cancer. Physicians studying just this topic include Dr. Jerome Posner of
Memorial Sloan Kettering Cancer Center and Dr. Robert Darnell of Rockefeller
University, both in New York City.
Some
hospitals doing research on PCD are:
Rockefeller
University - New York, NY (Dr. Darnell)
Sloan-Kettering
- New York, NY (Dr. Dalmau and Dr. Posner)
Duke
University, North Carolina (study of medication for treating
University
of Texas M.D. Anderson Cancer Center (Dr. Kurt Jaeckle)
What
about caregivers and family members?
It
is equally important that the caregivers get adequate support. The disorder
typically emerges suddenly and without warning. The neurological manifestations
of PCD are complex and often require the patient to have 24-hour care.
New caregivers need advice on how to deal with the limitations that the
neurological deficits can place on the patient's life. Many caregivers
will require quick access to information on caring for a disabled person.
This includes information on: social security benefits, insurance coverage,
handicapped licence plates, etc.; evaluations for physical therapy; medical
equipment: hospital beds, ultra-light wheelchairs, hand-held showerheads,
etc.; home healthcare and visiting nurses; social workers and other support
services; nursing home care or assisted living.
Where
can I turn for more information?
The
International Paraneoplastic Association is a grassroots organization dedicated
to helping patients and families cope with paraneoplastic disorders. The
Association also hopes to lobby for greater research into treatments and
cures. The Association maintains an email support group and web page for
people affected by paraneoplastic disorders. For information, contact Carolyn
Lawrence,
Other organizations that can provide more information:
American Autoimmune Related Diseases Association,
Inc.
National Institute of Neurological Disorders and Stroke
National Organization for Rare Disorders, Inc.(NORD)
The Neurology Fund
American Cancer Society, Inc.