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Definition:
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A
pancreatic islet cell tumor is an
uncommon tumor of the pancreas that
arises from a distinct type of cell in
the pancreas, the islet cell. Normally,
islet cells produce insulin and other
hormones, and islet cell tumors can also
produce hormones.
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Alternative Names:
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Islet
cell tumors; Islet of Langerhans tumor;
Neuroendocrine tumors
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Causes, incidence, and
risk factors: |
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In the
normal pancreas, cells called islet
cells produce hormones that regulate a
variety of bodily functions, such as
blood sugar level and the production of
stomach acid.
Tumors
that arise from islet cells of the
pancreas can also produce a variety of
hormones, though some do not. Although
islet cells produce many different
hormones, most tumors secrete only one
specific hormone that leads to specific
symptoms. Pancreatic islet cell tumors
can be benign or malignant (cancerous).
Islet
cell tumors include insulinomas,
glucagonomas, and gastrinomas (Zollinger-Ellison
syndrome). A family history of multiple
endocrine neoplasia, type I (MEN I) is a
risk factor for the development of islet
cell tumors.
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Symptoms:
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Sweating
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Tremor
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Rapid heart rate
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Anxiety
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Hunger
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Dizziness
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Headache
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Clouding of vision
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Confusion
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Behavioral changes
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Convulsions
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Loss of consciousness
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Skin rash that migrates on the face,
abdomen, perineum, buttocks, or lower
extremities
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May be crusty and scaly
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May have raised lesions filled with
clear fluid or pus
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Inflamed mouth and tongue
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Weight loss
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Weight gain (unintentional)
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Peptic ulcer pain
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Vomiting blood
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Diarrhea
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Abdominal pain
Note:
The symptoms depend upon the type of
tumor and the hormone produced.
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Signs and tests:
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The
type of tests performed may vary
depending upon the symptoms associated
with the condition. Some of the
following abnormalities may be detected
on testing:
- an
abdominal CT scan may reveal a
pancreatic tumor (sometimes the tumor
may be too small to see with a CT
scan)
- MRI
of abdomen to show pancreatic tumor (MRI
can sometimes see smaller tumors than
those seen with a CT scan)
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abnormal glucose tolerance test
- low
fasting glucose level
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elevated serum insulin C-peptide
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elevated serum insulin level
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increased gastrin level
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positive secretin stimulation test for
pancreas
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elevated fasting glucose level
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elevated serum glucagon level
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abdominal ultrasound
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endoscopic ultrasound
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intraductal endoscopic ultrasound
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occasionally, the diagnosis and
treatment (surgical removal) requires
exploratory surgery, during which the
surgeon feels the pancreas and may use
ultrasound probes
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Treatment:
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Treatment will depend upon the type of
tumor discovered and whether the tumor
is benign or malignant. Malignant tumors
spread to other organs, grow
aggressively, and may not be treatable.
In general, tumors are removed
surgically, if possible.
If
malignant cancerous cells spread
(metastasize) to the liver, a portion of
the liver may also be removed, if
possible. If the cancer is widespread,
various forms of chemotherapy may be
used to shrink the tumors.
If the
abnormal production of hormones is
causing problems, medications may be
given to counteract their effects. For
example, the overproduction of gastrin
in the case of gastrinomas results in
oversecretion of acid in the stomach,
and medications that block acid
secretion can be taken to reduce
symptoms. |
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Expectations (prognosis):
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Patients may be cured if tumors are
surgically removed before they have
spread to other organs. If tumors are
malignant, chemotherapy may be used, but
is usually unsuccessful at curing
patients. Death may result from serious
problems due to excess hormone
production (hormone crises), such as
very low blood sugar or from widespread
metastasis.
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Complications:
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Metastasis (spread) of the tumor to the
liver can occur. Hormone crises can
occur, depending on whether the cells
that make up the tumor secrete hormones
and what type of hormones are made.
Gastrinomas can induce severe ulcers in
the stomach and small intestine.
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Calling your health care
provider: |
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Call
your health care provider if symptoms of
this
tumor develop, especially if you
have a family history of MEN1.
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Prevention:
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There
is no known prevention for these tumors. |