Carcinoma of Unknown Origin Primary (CUP) Cancer

Carcinoma of unknown origin primary, or CUP, is a rare disease where malignant cancer cells are found in the body but the original place the cancer began is unknown. Cancer cells can form in any tissues or area of the body. Primary cancer refers to the original place the cancer began to grow before it spread or going through the process of metastasis. In some cases, many severe, specialists are not able to determine where the cancer has started, or which type of cancer it is. For these kinds of cancer patients, diagnosis may be carcinoma of unknown origin or occult primary tumor cancer.

Certain types of cancer are harder to give an origin point for than others. This is because many cancer cells look similar to others. As in, lung cancer cells can resemble breast cancer cells, and vice versa. In these cases, your CUP diagnosis may shift to which type of cancer you actually have once it is determined. In some cases, the primary cancer may never be found. This could be because the primary cancer is extremely small and slow growing, the body’s immune system fought against and killed the primary cancer, or the primary cancer was removed or treated during the surgical or medical intervention on another issue you may have had.

An example of this type of situation would be a woman testing positive for carcinoma of unknown origin cancer and having a hysterectomy around the same time to remove the issues she was having with her monthly menses. After the hysterectomy, she is now testing completely negative for cancer. This would tell her doctors that the CUP cancer was most likely in the uterus and was removed with surgery.

What are the signs of carcinoma of unknown origin cancer?

The signs and symptoms you experience with CUP cancer will vary depending on which areas of your body are affected. Often this type of cancer does not cause any readily visible symptoms at all. If symptoms are seen, most are first attributed to other illnesses, before testing for cancer begins. If you are experiencing any of the following signs, schedule an appointment with your doctor to cover all of the bases.

  • Pain in one part of the body that does not go away.
  • Thickening of skin or lump in any part of the body.
  • Fever for no known reason that is not controlled by medication and does not go away.
  • Changes in your bowel habits like constipation and diarrhea or changes in frequency of urination.
  • A cough that does not go away or a hoarse voice that does not recover within a normal time frame.
  • Unusual bleeding or discharge from anywhere in the body.
  • Night Sweats.
  • Sudden weight loss with no known reason or cause.

What tests are done to determine if I have CUP cancer?

There are certain tests that most people with suspected carcinoma of unknown origin primary cancer may have.

  • Urinalysis is done to check the urine and its contents like sugar, protein, blood, and bacteria.
  • Blood chemistry studies are done to check the blood to measure certain amounts of substances released into the blood by organs and tissues within the body. An unusual count or higher number of these can be a clear sign of disease.
  • Fecal occult blood tests are done to check your fecal output, or stool, for blood that can only be seen with a microscope. Small samples of stool are placed on special cards and returned to the doctor for testing. Certain types of cancers do cause bleeding, so finding blood in the stool can be a sign of colon or rectal cancer.
  • Physical examination and medical history is an exam of the entire body for overall health, including checking for all signs of disease, lumps, bumps, or abnormalities. Your history of medications and past treatments will also be recorded.
  • Complete blood count is a procedure where a sample of the blood is drawn and tested for these things: number of red blood cells, white blood cells, and platelets; the amount of hemoglobin in red blood cells; and the portion of the sample made up of red blood cells.
  • If these tests prove that there may be cancer in your body, further testing may be done which will include a biopsy. A pathologist will view your tissues under the microscope to determine the type of biopsy you may need.
  • An excisional biopsy is the removal of the entire lump or tissue abnormalities.
  • Fine needle aspiration biopsy is the removal of tissue or fluids from the body using a thin needle.
  • Core biopsy is the removal of tissue using a wide-gauge needle.
  • Incisional biopsy is the removal of part of the lump or a sample of the abnormal tissue.

If cancer cells are found in your samples after your biopsies, further testing and labs will be done and used to determine the type of cancer that you do have.

  • Immunohistochemistry is a test that uses the bodies antibodies to check for certain antigens in the samples. Certain cells changes are linked to specific types of cancer.
  • A histological study is a laboratory test where stains are added to a sample of your cells and then checked under a microscope.
  • Reverse transcription-polymerase chain reaction or RT-PCR test is a lab test where cells in a sample of your tissue are studied using chemicals to watch for changes in the genes.
  • A cytogenic analysis is a lab test where cells in your sample of tissue are viewed under a microscope to look for changes in the chromosomes. Certain chromosomal changes are linked to specific types of cancer.
  • Electron and light microscopy are lab tests where your tissue sample is viewed under regular and high-powered microscopes to find any abnormalities in the cells.

What types of tests are done after the cancer has been found?

Tests that are done after a cancer diagnosis are more commonly known. The use of a CT scan machine, MRI imaging, PET scans, mammography, endoscopy and tumor marker tests are some that are frequently done on those patients with varying types of cancer. In spite of all of these tests, in some cases, the specific type of cancer or its original origin may never be found. When this happens, your doctor will base your treatment plan on the most likely type of cancer causing your trouble.

Are there factors that can determine a negative or positive outcome with CUP cancer?

Your prognosis with carcinoma of unknown origin primary cancer, as with any cancer, depends on a number of the following:

  • How long you have had cancer, or if it is reoccurring.
  • Whether you are male or female.
  • The way your tumor cells present when checked under a microscope.
  • The number of organs in your body with cancer in them.
  • Where the cancer began in your body and where it has spread.

For most patients dealing with carcinoma of unknown origin primary cancer or CUP, treatments do not cure the cancer. There are numerous clinical trials being done all around the country to learn and improve the treatments for this specific type of undefined cancers. If you suspect you may have CUP cancer, schedule an appointment with your medical care team to begin the proper testing to find your diagnosis. Early diagnosis and detection are key to whole healing.

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