Which patients are eligible for treatment?
Because not all types of cancer are equally sensitive to dendritic cell vaccination, the treatment method is currently applied to various types of cancer:
- Hereditary Non-Polyposis Colorectal Cancer (HNPCC) / Lynch syndrome (a type of colon cancer)
- Melanoma (a type of skincancer which also occurs in the eye)
- Prostate cancer
- Kahler’s disease/ Multiple myeloma (a cancer of the blood cells)
- Malignant lymphoma after stem cell transplantation
The objective is to expand the selection with more types of cancer in the future.
The patient has to be in a good condition, may not have received any chemotherapy in the last month and may not have any metastases in the brain. Also, with a few exceptions, he or she may not have had other tumours in the past five years. If the patient believes he is eligible for this experimental treatment, he may contact his own oncologist or surgeon and ask for a referral letter. The attending physician may then send the necessary medical information to the clinical departments of the Radboudumc.
Before treatment the patient will first be examined to ascertain that he is a suitable candidate for the vaccination program. A physician will see the patient in an outpatient clinic of the Radboudumc and blood will be taken. The blood will be examined to ascertain the value of several parameters. Also tumour material will be requested in order to test whether the tumor will be sensitive to the vaccination. This entire procedure will take two to three weeks.
If the results of the blood analysis are correct and the tumor meets all the criteria, the patient may be treated with the vaccine. In principle, each patient receives three vaccinations. The TIL needs to obtain a large amount of white blood cells to generate enough dendritic cells for three vaccinations. After training the dendritic cells to recognize the cancer cells and activate the patient’s immune system, the cells are ready to be given back to the patient by way of a vaccination. The immune system’s response will be monitored using a skin test. If the disease stabilizes or improves, the patient will be considered for revaccinations after half a year and after a year time. In case of revaccinations, the TIL will check whether there are enough dendritic cells left in stock or whether there is need for a new apheresis. The patient’s immune response will be monitored in the same manner as before.
Potential side effects
Possible side effects after vaccination are: fever, shivering and fatigue. These complaints may occur up to two days after vaccination and usually disappear within a few days. If necessary these complaints may be treated with acetaminophen/paracetamol.
Apart from the above complaints, patients may also experience vitiligo; this is discoloration of sections of the skin. This depigmentation is caused by the fact that normal skin cells bear the same characteristics (marks) as the malignant melanoma cells. The discoloration may occur anywhere on the body and its range cannot be predicted. The depigmentation is permanent, but only seen in few patients.
Aplogies, the left menu is not accessible in english yet. Underneath you can find the text of the step-by-step treatment walkthrough.
Step 1: Apheresis
During the apheresis immune cells are extracted from the patient’s blood. The patient is hooked up to the centrifuge with two venipunctures (needles), one in each arm. The patient’s blood flows through one venipuncture towards the centrifuge. In the centrifuge, the immune cells that the Tumor Immunology Laboratory (TIL) needs to create the vaccine - a specific kind of immune cells called ‘monocytes’ - are separated from the patient’s blood. The remainder of the blood is returned to the patient through the other venipuncture. The entire apheresis takes three to four hours.
Step 2: Processing
After the apheresis, the isolated immune cells are brought to the Tumor Immunology Laboratory (TIL) for further processing. Lab technicians grow the monocytes to dendritic cells and ‘train’ them to recognize (the patient-) specific cancer cells. Among other things, they do this by bringing the dendritic cells in contact with characteristic particles of the patients cancer cells. The lab technicians perform all of these steps in cleanrooms, special laboratories where no bacteria, other germs or particles could come in contact with the patient’s cells.
Step 3: Vaccination
Once the lab technicians have trained the dendritic cells to recognize the cancer cells, the dendritic cells are ready to be returned to the patient. The cells are returned through a vaccination by way of an infusion and/or injection in the skin or a lymph node. The vaccination takes about fifteen minutes, after which the patient will be kept for some time for observation.
Patients will be vaccinated thrice, with two weeks intervals. After the second and third vaccination a blood sample is taken to monitor how the immune system reacts to the vaccine. In addition, a skin test is performed after the third vaccination.
Step 4: Skin test
After the third vaccination, a skin test is performed by injecting dendritic cells in the skin at four points in a small area on the back of the patient. The injected cells are the same dendritic cells that were given to the patient in the vaccine. This is to check that the cancer-fighting T cells have spread throughout the body. These injections will take about fifteen minutes.
After two days, the dermatologist will examine the skin at the Dermatology Department. He will do a biopsy (remove a small section of skin with a diameter of no more than ¼ inch) of the four injection points under local anaesthesia. The wound will be stitched and will leave a small scar. This procedure takes about half an hour.
From the biopsies of the skin test immune cells are isolated to analyze the immune system’s reaction to the vaccine.