**2. Definitions**

cultural shift into the research of various topics including medical errors and their prevention. More specifically, health care initiatives concerning public reporting of outcomes, provider and institutional reimbursement, and methods to improve existing systems, combined with individual accountability, were introduced. Beyond public and private agency investment, government involvement was also increased with the Agency for Health Care Research and Quality providing funds for identification of best practices, in addition to patient safety indicators and standardizing metrics. Despite the above measures, contemporary analyses suggest that medical errors may actually result in over 400,000 deaths per year [2], with the U.S. Department of Health and Human Services Offices of the Inspector General reporting 180,000 deaths resulting from medical errors among Medicare beneficiaries in 2008 [3], and an annual cost exceeding \$17 billion [4].

Medical errors continue to illuminate the fragility and complexity of the medical system. Within this context, it is critical to point out that most of these errors are potentially preventable [2]. For example, it has been estimated that roughly 1 in 113,000 surgical procedures involve an incorrect operative intervention [5]. Subsequent analyses performed by the Joint Commission further revealed that communication errors (70%), procedural noncompliance (64%), and leadership (46%) were significant contributors to such events. However, other commonly cited antecedents to sentinel events include team competency, availability of information, organizational culture, failure to mark or clearly mark the operative site, inadequate medical record review, and of paramount importance, deficient continuum of care [6]. It is important to recognize the systemic and procedural breakdowns that often preclude postdiagnostic procedures that may not be operative in nature but may be catastrophic for the

There are two broad categories of occurrences in terms of potentially introducing serious

• **Practical errors**, which involve the production of patient samples into therapeutically rel-

• **Interpretative errors**, which concern the processing of these diagnostic data into a report

At the same time, reporting of errors that occur across the various sub-specialties of laboratory medicine often proves difficult. For example, validated studies have demonstrated increased propensity toward error through the inherent systematic complexity (e.g., due simply to the increasing number of process-related steps) [7]. Surgical pathology is particularly vulnerable to breaches in patient safety, in part due to the wide variability in tissue types, anatomic nuances, biologic sampling, inconsistency and human involvement in diagnostic interpretation, as well as time constraints (and pressures) [8]. The Quality Practices Committee and College of American Pathologists (CAP) designed validated guidelines and metrics in laboratory quality, with data collection and peer review initiatives such as Q-PROBES (a peer-comparison quality assurance service offered by the College of American Pathologists that was created in 1989), in order to establish patient safety benchmarks [9]. However, despite increased awareness, the necessity of improving pre-existing pathology paradigms has only been considered recently [10]. Additionally, an expert panel from The CAP, as well as the Pathology and Laboratory Quality Center, in association with the Association of Directors of

patients if improperly conducted (or erroneously delivered and/or interpreted).

for use in the subsequent step(s) along the patient's care continuum.

medical errors into the arena of laboratory medicine:

evant data, and

142 Vignettes in Patient Safety - Volume 3

In order to familiarize other surgical subspecialties with potential procedural weaknesses within the pathology workflow, a conceptual framework of practical and interpretative errors derived from Meier [12] is outlined (**Table 1**). A brief overview of the taxonomic


structure of altered case reports will be provided, which constitutes one way of identifying error in pathology. **Figure 1** highlights significant sources of error in both of these processes [13, 14]. It is of paramount importance for providers to understand the limitations of research in the current literature regarding the preponderance/magnitude of potential and actual error that exists in pathology (as well as the common failure modes in such settings) (**Figure 2**).

**3. Clinical vignette #1**

samples did not originate from the same patient.

vision.

Shahar et al. [16] described a 47-year-old man who presented to the emergency room after reports of progressive right lower extremity weakness. Relevant history included 40-packyear of tobacco abuse as well as upper-limb dysmetria. Magnetic resonance imaging (MRI) revealed distinct ring-enhancing lesions in the left frontal lobe of the brain, which were biopsied and reported as metastatic small cell lung carcinoma. The patient received radiation treatment for increasing right lower extremity weakness, headache, and blurred

Patient Safety Issues in Pathology: From Mislabeled Specimens to Interpretation Errors

http://dx.doi.org/10.5772/intechopen.79634

145

**Figure 2.** Brief overview of common errors in the pathology workflow; derived from Zarbo et al. [15].

The patient demonstrated worsening lethargy and headache prompting a brain computed tomography (CT) that showed an enlarging mass with midline shift. Histopathological examination suggested glioblastoma with no evidence of metastatic carcinoma. Despite suspicion of a possible rare "collision tumor" (a tumor specimen from a single patient in which pathology reports do not coincide), DNA sequencing of the two biopsies was performed to determine if the tumor was monoclonal. Several genotypic and microsatellite analyses revealed that the

**Figure 1.** Relative frequency of errors occurring during practical/systemic and interpretive/diagnostic processes. (**A**) Reasons for clinical lab error prior to delivery of sample for interpretation. These errors are not differentiated between pre- and post-verification [13]. (**B**) Data for cases of medical negligence resulting in practice considered below the standard of care. Clinical pathology refers to laboratory error, practical error refers to system errors, miscellaneous surgical pathology errors refer to claims which show no pattern in specimen diagnostic criteria and are considered random, and other repetitive pattern errors include sarcomas, lymphoma, lung, gastric, fine need aspirates, prostate, bladder, and nongynecologic cytology errors; 57% of claims are from practical errors, melanoma, breast, Papanicolaou, and gynecologic samples [13, 14].

Patient Safety Issues in Pathology: From Mislabeled Specimens to Interpretation Errors http://dx.doi.org/10.5772/intechopen.79634 145

**Figure 2.** Brief overview of common errors in the pathology workflow; derived from Zarbo et al. [15].
