Frequently Asked Questions


If we have not answered your question here please contact our client services department and include your question in the message.

Why is the know error® system necessary?

The biopsy evaluation process can include up to 18 complex steps and several medical professionals working in different locations. Each year, it plays a critical role in determining the diagnoses and corresponding treatments of millions of patients. With such a complex process executed at a large scale, the risk of Specimen Provenance Complications (SPCs) (switched and contaminations) is a serious concern for both physicians and patients. The know error® system which includes a DNA Specimen Provenance Assay (DSPA) can increase diagnostic accuracy by identifying otherwise undetected SPCs.

Will the patient’s DNA information be safe?

Collected patient DNA will ONLY be used for tests ordered. Personal information will never be sold or shared and is protected by the Health Insurance Portability and Accountability Act (HIPAA), a U.S. law designed to provide privacy standards to protect patients’ medical records and other health information provided to health plans, doctors, hospitals and other health care providers. To review our comprehensive privacy policy, please refer to

Do you run the DNA Specimen Provenance Assay (DSPA) looking for cancer?

Strand is not a pathology lab and does not diagnose cancer, but rather facilitates the process of increasing diagnostic accuracy by confirming that the biopsy tissue is free from contamination (i.e. the samples are pure) and the tissue matches the DNA from the reference sample supplied to Strand.

Does use of the know error® system affect my relationship with my current pathology lab?

Your pathology lab will continue to provide pathology services as it is doing so today. If the biopsy results return positive for cancer, a small piece of the paraffin block (or an extra, unstained slide) used to render the diagnosis will be sent to Strand to perform a DNA Specimen Provenance Assay (DSPA) test. The physician’s office and the pathology lab utilize DSPA in order to increase diagnostic accuracy by reducing Specimen Provenance Complications (SPCs) and complying with MolDx/CMS requirements to verify the source and purity of genomic test results.

What are Specimen Provenance Complications (SPCs)?

Specimen Provenance Complications (SPCs) encompass a wide spectrum of error conditions including specimen transposition(switches), extraneous/foreign cell contamination, and patient misidentification that occur in clinical or anatomical pathology. Occult SPCs can lead to serious diagnostic mistakes and adverse patient outcomes.

What happens if a non-match is detected?

A client services representative will call the designated contact immediately to report the issue. We will conduct additional research to ensure someone internally is not the source of the non-match. Once that is verified, we strongly recommend that the lab re-cuts the block(s) in question to make new slides, has pathology read those slides for diagnosis and send unstained slides for confirmation testing. A summary of the initial findings and an addendum to the original lab report will be issued within 2-3 days following receipt of the new tissue samples.

What are the different types of non-match results that may occur?

We segment the different types of non-match results into four main categories:

  1. Specimen transposition (switches)– tissue contains entirely different DNA profile than the reference sample DNA
  2. Extraneous/foreign cell contamination– second DNA source is present in addition to the reference sample DNA
  3. Quantity/quality not sufficient (QNS)– DNA is not of sufficient quantity or quality to provide a profile we can compare with the reference sample DNA
  4. Genetic anomaly– discrepancy due to genetics of tissue sample
What is a genetic anomaly and how do you identify one?

A genetic anomaly occurs when the patient’s cancer causes a mutation in the cells of the tissue sample and gives the appearance of a non-match. In order to confirm the existence of a genetic anomaly, we must re-cut and re-test the tissue. If this yields the same result, we can confirm that the non-match is due to a genetic anomaly.

What extra steps must my office take to use the system?

The know error® system involves minimal steps and can be implemented with little disruption to the standard biopsy collection process, regardless of whether pathology services are performed in-house or by a reference lab partner.

The few extra steps include: 1) obtaining patient consent, 2) swabbing the patient’s mouth and 3) returning the swab in the provided mailer to the DNA lab. Strand Diagnostics provides training for the medical professionals and staff involved in the collection process.

Typically, orders for DSPA are generated whenever a positive cancer diagnosis is rendered on a tissue(s). When DSPA is being ordered, the pathology lab should cut two(2) 4-micron slices from the appropriate paraffin block(s) and send to Strand Diagnostics using the supplied transport vials from the Know Error biopsy kit. Unstained slides may be sent instead.

What types of tissues do you accept for DSPA testing?

Strand routinely tests breast and prostate tissues. Other tissue types with which Strand has experience include bladder, cervical, colon and endometrial. If you are interested in utilizing the know error® system or wish for DSPA testing on tumor types outside of what is listed, Strand can further investigate to determine clinical feasibility on a case-by-case basis.

How long does it take to receive the final Know Error DSPA report?

Turn-around-time is 5-6 calendar days for prostate tissue and 2-3 calendar days for breast tissue. Time frames vary for other tissue types that are not routinely tested at our lab.

How do I order UroSeq® or other gene panel tests from Strand?

If a prostate patient meets the recommended guidelines and your practice utilizes the know error® system, you can simply order Strand’s UroSeq® Hereditary DNA Repair Gene Panel through client services. In some cases, a practice may be able to establish “reflex” orders of UroSeq® testing. Other practices may call Monday through Friday, 8:00 a.m. to 5:00 p.m. ET at 1-888-924-6779 and select option 2 to speak with a client services representative.

What genes are analyzed as part of the UroSeq® gene panel?

Strand’s UroSeq® Hereditary DNA Repair Gene Panel testing includes BRCA1, BRCA2, ATM, CHEK2, HOXB13, PALB2 and RAD51D and the Lynch Syndrome genes MLH1, MSH2, MSH6, PMS2, and EPCAM.

How long does it take to receive a UroSeq® report?

Turn-around-time is approximately 2 weeks from the receipt of both the buccal swab (which may have been submitted as part of the know error® system) and the test order.

If I utilize the know error® system, do I need to order a special kit for UroSeq® testing?

No, conveniently, the DNA reference swabs in the Know Error kit collected at the time of biopsy are sufficient for germline DNA analysis and the hereditary gene panels offered by Strand. No additional patient visit or specimen collection is required.

Call 1-888-924-6779 and select option 2 (Monday – Friday 8 am to 5 pm ET) for a client service representative to answer questions or to get you started using UroSeq with the know error system.

What if the UroSeq® Hereditary DNA Repair Gene Panel are positive for mutations?

If a patient tests positive for a germline mutation in any of the genes in Strand’s UroSeq panel, Strand takes the following actions:

  1. Strand Client Services treats a positive finding as very serious, and thus sends both an email to the practice and calls the practice to convey the message LIVE (no voice mails).
  2. Strand Client Services provides to the practice a suggested written communique intended for the patient advising him to seek genetic counseling (from Strand, or from anywhere the patient deems worthy).
  3. Strand Client Services stands ready to receive a call from the patient for scheduling a free consult with a genetic counselor. (To schedule a consultation, the patient calls Strand Client Services at 1-888-924-6779 x119).
  4. Strand’s Medical Affairs personnel are notified and are ready to consult with the treating physician and/or navigator as to what the positive findings mean. (To schedule a consultation, the physician calls Strand Client Service at 1-888-924-6779 x119 8am to 5pm ET M-F).
  5. If the patient does speak with a genetic counselor arranged by Strand, notes are subsequently sent to the treating physician or his/her administrator documenting that conversation as well as the recommendations provided to the patient.