NeuroSpine Center of Wisconsin and Oncotech Now Offering Chemoresistance Testing for Brain Tumor Patients

Neurospine Center of Wisconsin and Oncotech Now Offering Chemoresistance Testing for Brain Tumor Patients

Brain tumors account for just 1% of all cancers, yet they remain one of the most deadly. While a cure for most brain tumors has not yet been found, treatment options are improving at a rapid rate. Brain tumor patients are routinely treated with a one-two-three approach.

One: Surgery
Two: Radiation
Three: Chemotherapy
Surgery is an evolving effort, recently enhanced by the use of the Stealth (frameless stereotaxy), and in the future, intraoperative MRI scanning. Gross total resection is the surgical goal, as this gives the patient the very best chance at a positive outcome.

Radiation therapy has seen drastic improvements with stereotactic radiosurgery, IMRT, and most recently GliaSite implantable radiation.

As new chemotherapies are developed, a challenge has remained: Will the tumor cells respond to that particular drug? In an effort to optimize the outcomes for these patients, NeuroSpine Center of Wisconsin is now offering chemoresistance testing for all of our brain tumor patients. At the time of surgery, a portion of the tumor is sent to Oncotech, a company in Tuscan, California, for processing. The tissue is then tested for resistance to a list of chemotherapy drugs selected by the surgeon and/or the oncologist. The results allow the physicians to properly select drugs that the tumor is least resistant to, thus giving the greatest chance of effectiveness. Results are sent back to the surgeon within a week, allowing adequate time to analyze the EDR assay, or Extreme Drug Resistance Assay. The following is information provided by Oncotech on this service.

The EDR Assay provides information that can be critical to your care, by identifying chemotherapy drugs that are unlikely to be effective.

The Extreme Drug Resistance (EDR) Assay is an advanced laboratory test for cancer, also known as a “chemotherapy drug resistance test.” This test is performed by growing a portion of the cancer tumor in the presence of different chemotherapy drugs in the laboratory. If the cancer cells grow in the presence of a very high (extreme) dosage of a chemotherapy drug, studies have shown that the cancer is unlikely to respond to that drug in the patient’s body. The test results are usually released to the treating physician within 10 days of specimen receipt, so that the physician can select the best chemotherapy regimen for the patient, without wasting valuable treatment time.

EDR Assay results have been widely published in scientific literature and have been shown to be 99% accurate in clinical trials. An extensive bibliography, which you may choose to review with your physician, is available for downloading at EDR Assay results can always be used within standard guidelines for the treatment of any cancer type.

By eliminating inactive drugs from the therapy regimen, use of the EDR Assay avoids exposing patients to the toxicity of those drugs that are unlikely to be effective in treating the tumor and can help to improve the quality of life of the cancer patient during treatment.

If you have been diagnosed with cancer and will be having surgery, your tumor can be sent for this special testing by your surgeon.

The Extreme Drug Resistance Assay requires living viable tumor cells to perform the assay. A specimen that is paraffin embedded, fixed, minced, or frozen cannot be used. In addition, patients must not have had chemotherapy or radiation therapy within 3 weeks of specimen collection. The assay can also be performed on other samples containing cancer cells, on malignant fluids, for example.

If the patient is a potential candidate for chemotherapy treatment for cancer, the physician must order the test immediately following surgery. The decision to order the test is usually made prior to surgery so that the appropriate specimen handling materials can be ordered from the laboratory in advance in order to assure they are available at the time of surgery.

Over 80,000 cancer patients have had their tumors tested by the EDR Assay.

If you have questions about the Extreme Drug Resistance (EDR) Assay, you can visit the Oncotech website at for further information. Representatives are available in every region of the United States to answer your physician’s questions, or to facilitate the ordering of the test. For additional information regarding Oncotech services, please have your doctor call an Oncotech representative at (800) 576-6326 for assistance.

Frequently Asked Questions

What is the Oncotech EDR Assay?

The Extreme Drug Resistance Assay (EDR) Assay is a laboratory test performed on a patient’s tumor cells. This lab test can determine the probability of a tumor’s resistance to a specific chemotherapy drug. If the tumor cells grow in the presence of very high concentrations of chemotherapy drug, then the cancer cells are considered resistant to that drug.

How does the EDR Assay help the cancer patient?

Once the EDR testing is completed on a patient’s tumor cells, a lab report is created which shows the probability of resistance for each chemotherapy drug tested. Drugs that are shown to be in the Extreme Drug Resistance range are evaluated by the patient’s physician in order to determine the best course of treatment. Often, this means preventing unnecessary patient exposure to toxic, ineffective chemotherapy drugs.

Is the EDR Assay right for me?

Only your doctor can determine if the EDR assay or any of Oncotech’s other cancer testing services are right for you. Please ask your physician about Oncotech’s Extreme Drug Resistance Assay and prognostic and predictive marker services.

How much does it cost?

Oncotech bills insurance directly and does not balance bill the patient. Patients may be responsible for co-payments or unmet deductible amounts where required by law or insurance contract. Oncotech has negotiated reimbursement contracts with many of the country’s leading insurance carriers, including many managed care organizations. A Social Security Administrative Law Judge has determined that Extreme Drug Resistance Assays are “part of the generally accepted medical practice” and are “not experimental.” Oncotech bills Medicare directly on an accept assignment basis. Oncotech will assist patients in obtaining reimbursement and may provide indigent coverage where appropriate.

How do I get these tests ordered for me?

Your physician can directly order Oncotech laboratory tests if he or she has determined that the EDR Assay or other Oncotech cancer testing services are right for you. The physician’s office can call 1-800-ONCOTECH for requisition forms and specimen handling guidelines.

How long do results take?

Results for the EDR Assay are available in 7 days. Prognostic/predictive marker results are available in 3 days. Other laboratory services vary depending on specific test ordered.

How do I get more information?

More information is available by contacting an Oncotech representative directly at (800) 576-6326. Or e-mail us at

You may also call David Bond APNP, CNRN at NeuroSpine Center of Wisconsin at 920-882-8200 for information on Oncotech testing and other services available to brain tumor patients.

For more information call 920-882-8200 or 1-888-231-5236

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