Strand Diagnostics provides advanced forensic services that enhance patient safety

Sept. 22, 2013

Laura Beggrow



Joined Strand Diagnostics in January 2013; previously served as Vice President of U.S. Sales and Marketing at Genomic Health.


Bachelor of Science Degree in Nursing from Ohio State University.


I enjoy traveling and learning about different cultures and people.

Strand Diagnostics is a comprehensive molecular diagnostic testing company using cutting-edge technology focused on advanced forensic services. Our laboratory has a healthcare division that developed and markets the know error® system used by physicians and laboratories to ensure patients are always matched with the appropriate diagnosis. This unique system also provides value in the research setting by protecting the integrity of clinical data by detecting any instances of specimen handling error and/or fraudulent activity related to data representation.

The know error system helps to safeguard patients from possible diagnostic and treatment errors. With the biopsy evaluation process requiring nearly 20 steps and several medical professionals involved in the biopsy diagnostic testing cycle, there are a number of specimen provenance complications that can arise. The core features of the know error system include: unique patient identification barcoding; forensic chain of custody; providing strict means of control and documentation of all samples; DNA specimen provenance assignment (DSPA) testing; and a conclusive report summarizing individual patient findings.

The know error system involves three steps that are simply implemented during the standard biopsy collection process. The first step is a reference sample of DNA, taken by swabbing the inside of the patient’s cheek. This swab is sent to our independent DNA lab. Next, the patient’s biopsy tissue sample(s) are placed in barcoded specimen containers and sent to the pathology lab for evaluation. Last, if the biopsy results are positive for cancer, our DNA laboratory performs a DSPA test to compare the DNA profiles of the biopsy tissue and the reference sample. Concordance of these DNA profiles allows for absolute confirmation of the patient’s identity. The only role of a pathologist in the implementation process of the know error system is to oversee cutting and sending of the appropriate tissue scrolls for DSPA testing.

The value of DNA testing on biopsy samples has been confirmed by scientific studies. In January 2013, the American Journal of Clinical Pathology published an article by John D. Pfeifer titled “Rate of Occult Specimen Provenance Complications (SPCs) in Routine Clinical Practice.” This publication documented the rate of occult SPC occurrence through prospective analysis of more than 13,000 prostate biopsies performed using the know error system. The results indicated that up to 3.5% of the specimens evaluated may not have come from the patient being diagnosed. With each case involving at least two individuals, the error rate actually underestimates the percentage of patients potentially affected by incidents of biopsy misidentification. Furthermore, these errors were found across a variety of practice settings and diagnostic laboratories.

Dr. Pfeifer also studied the cost-effectiveness of DNA-based short tandem repeat testing (STR), which was published in 2012 in Value in Health. Results indicated the STR-based testing would likely be a cost-effective method for preventing treatment errors resulting from biopsy misidentification, and that health policymakers should consider covering the cost of testing.

In the last couple of years, two additional studies have looked at DNA in the biopsy process. One study, published in 2007 in the Journal of Urology, found the medical community may be ready for a “DNA time-out,” or pause to confirm DNA against a malignant specimen, to address the problem of biopsy switching errors. In 2011, the Journal of Clinical Oncology published a study that found, “The potential for biopsy mismatches in clinical trials and clinical practice is an under-recognized problem that requires rigorous attention to details of chain of custody and consideration of more widespread DNA identity testing.”

Evolving solutions in specimen provenance are valuable tools for laboratorians. Strand Diagnostics is significantly improving the quality of healthcare delivery by arming physicians with the ability to deliver results accurately and in a timely manner, ensuring that the right treatment is being delivered to the right patient.

To date, we have received more than 106,000 patient samples at our laboratory. The know error system protects these patients from undetected specimen provenance complications (SPCs)—including specimen mislabeling and undetected tissue transposition or contamination. In the absence of know error testing, SPCs occur in as many as 3.5% of patients diagnosed with cancer.

When a patient is told he or she has cancer, it’s critically important to ensure the correct patient is identified. The results of misidentification can be catastrophic for the patient and the physician. Many documented cases show firsthand how errors can set into motion life-altering, often drastic treatment measures, including the removal of healthy tissue in cancer-free patients. Mistakes can also delay life-saving treatment for patients with cancer.

The know error system also plays a critical role in personalized medicine—an approach that has gained momentum in the past few years and aims to improve patient care. I feel strongly that confirming a diagnosis must be the first step of any customized
treatment plan.

Expansion opportunities are being explored. The incorporation of cutting-edge forensic technology into our forensic services, and the expansion of our know error system for other cancers, remain top priorities for our organization. We are also exploring ongoing opportunities to expand in the clinical trial setting. Additionally, we continue to offer our services in a retrospective manner for any laboratory or clinic where a biopsy sampling error is suspected.