Effect of Lean method implementation in the histopathology section of an anatomical pathology laboratory

Background:

In the USA, the lack of processes standardisation in histopathology laboratories leads to less than optimal quality, errors, inefficiency and increased costs. The effectiveness of large-scale quality improvement initiatives has been evaluated rarely.

Aim:

To measure the effect of implementation of a Lean quality improvement process on the efficiency and quality of a histopathology laboratory section.

Methods:

A non-concurrent interventional cohort study from 1 January 2003 to 31 December 2006 was performed, and the Lean process was implemented on 1 January 2004. Also compared was the productivity of the Lean histopathology section to a sister histopathology section that did not implement Lean processes. Pre- and post-Lean specimen turnaround time and productivity ratios (work units/full time equivalents) were measured. For 200 Lean interventions, a 5-part Likert scale was used to assess the impact on error, success and complexity.

Results:

In the Lean laboratory, the mean monthly productivity ratio increased from 3439 to 4074 work units/full time equivalents (p<0.001) as the mean daily histopathology section specimen turnaround time decreased from 9.7 to 9.0 h (p = 0.01). The Lean histopathology section had a higher productivity ratio compared with a sister histopathology section (1598 work units/full time equivalents, p<0.001) that did not implement Lean processes. The mean impact, success and complexity of interventions were 2.4, 2.7 and 2.5, respectively. The mean number of specific error causes affected by individual interventions was 2.6.

Conclusion:

It is concluded that Lean process implementation improved efficiency and quality in the histopathology section.

Pathologists' assistants practice: a measurement of performance

Despite their widespread utilization, little is known about the quality of pathologists' assistants' services. Pathologists' assistants' performance was compared with pathology residents' performance using the metrics of lymph node retrieval and tissue resubmission rates. Lymph node retrieval was calculated by retrospective review of surgical pathology reports from a sample of axillary dissection, mastectomy, and colorectal specimens. Tissue resubmission rates were calculated by retrospective review of a sample of general surgical pathology reports. Pathologists' assistants retrieved a significantly greater total number of lymph nodes compared with pathology residents; however, there was no difference in the total number of positive lymph nodes retrieved. Cases for which pathologists' assistants performed the gross examination had a significantly decreased resubmission rate compared with those performed by residents. In this setting, the gross examination performance of pathologists' assistants was equivalent to or superior to that of pathology residents. These results provide the first information available relating to pathologists' assistants' performance in surgical pathology.

Interobserver variability associated with the MIB-1 labeling index: high levels suggest limited prognostic usefulness for patients with primary brain tumors

BACKGROUND

The use of the MIB-1 labeling index (LI) as a potential prognostic marker for patients with primary brain tumors is controversial. Many studies advocating its prognostic usefulness have suggested discrete MIB-1 LI cut-off values, above which patients have significantly worse outcomes. However, interobserver variability associated previously with MIB-1 LI calculation has not been reported despite the fact that the degree of interobserver variability impacts the clinical usefulness of such cut-off values.

METHODS

MIB-1 LIs were calculated independently using a standardized protocol by six pathologist observers for 50 astrocytic gliomas of varying grades. The level of interobserver agreement was determined by calculating kappa statistics for pairwise pathologist comparisons using MIB-1 LI cut-off values of 2.5%, 5.0%, 8.0%, 11.0%, and 15.0%. Spearman rank correlation coefficients were used to assess the pairwise associations between observer MIB-1 LIs.

RESULTS

Although there was general agreement among pathologists regarding whether an MIB-1 LI for a given astroglial tumor was low, moderate, or high based on the analysis of correlation, a high level of interobserver variability was associated with the determination of specific MIB-1 LIs. The highest level of agreement occurred using a cut-off value of 5.0%, with pairwise kappa statistics for this value ranging from 0.52 to 0.80.

CONCLUSIONS

The high level of interobserver variability suggests that proposed discrete MIB-1 LI prognostic cut-off values most likely are not useful clinically for predicting outcome for individual patients with primary brain tumors. Further prospective studies are needed investigating the prognostic usefulness of MIB-1 LI ranges that optimize interobserver agreement.

Microtubule-associated protein-2: a new sensitive and specific marker for pulmonary carcinoid tumor and small cell carcinoma

Microtubule-associated proteins (MAPs) are a major component of cytoskeleton family proteins associated with microtubule assembly. MAP-2 has been shown to be specifically expressed in neuronally differentiated cells. Pulmonary neuroendocrine carcinomas such as carcinoid tumors and small cell carcinomas are derived from neuroendocrine cells. We hypothesize that neuroendocrine cells may also express MAP-2, and therefore, MAP-2 may be used as a marker for pulmonary carcinomas of neuroendocrine differentiation. To investigate the utility of using MAP-2 expression to separate pulmonary neuroendocrine from non-neuroendocrine tumors, we examined the expression of MAP-2 immunohistochemically in 100 cases of pulmonary carcinomas. The immunoperoxidase method with antigen retrieval was used to characterize the expression of MAP-2, chromogranin, synaptophysin, and neuron-specific enolase in 25 small cell carcinomas, 25 carcinoid tumors, 25 adenocarcinomas, and 25 squamous cell carcinomas. All tumors were lung primaries. All 25 cases of carcinoid tumors (100%) as well as 23 of 25 cases (92%) of small cell carcinomas were positive for MAP-2. Four of 25 cases (16%) of adenocarcinomas were positive for MAP-2 and synaptophysin. Among the 25 squamous carcinomas, 4 cases (16%) were positive for MAP-2, 2 cases (8%) were positive for synaptophysin, 11 cases (44%) were positive for neuron-specific enolase, and none was positive for chromogranin. In conclusion, MAP-2 is a new sensitive and specific marker for the pulmonary tumors of neuroendocrine differentiation. We recommend that MAP-2 be added to immunohistochemical panels to separate non-neuroendocrine from neuroendocrine lung tumors.

National practice characteristics and utilization of pathologists' assistants

OBJECTIVE

To obtain descriptive information regarding the practice characteristics and utilization of US pathologists' assistants.

DESIGN

A self-administered, mailed, voluntary, anonymous questionnaire was distributed to a cross-sectional sample of 515 US pathologists' assistants registered as members of the American Association of Pathologists' Assistants. The questionnaire contained items relating to subject demographics, practice characteristics, specific task performance, and amount of time spent per day on the performance of specific tasks. Descriptive statistics were used to describe the data in terms of measures of central tendency and dispersion.

RESULTS

The response rate was 66.8%. The majority of questionnaires sent and received were from East Coast regions. Of all respondents, 46.6% were women, 57.6% were less than 40 years old, and 60.0% had been practicing 10 years or less. Over half (54.0%) had a master's degree. Almost the entire sample reported working 30 or more hours per week, with 43.4% reporting working more than 40 hours per week. The majority reported earning annual salaries between $56 000 and $75 000. Although task analysis of responses revealed a wide range of responses, the majority of the sample reported spending most of their daily time performing surgical specimen gross examinations (median 300 min/d). Approximately half of respondents also reported spending up to 90 minutes per day on nonspecific tasks such as logging specimens and answering the phone. Most respondents reported spending more daily time on such nonspecific tasks than on autopsy prosection or research.

CONCLUSIONS

To our knowledge, this national survey provides the first description of pathologists' assistants across the United States. These data provide a useful tool for tracking changes in the profession.

Clinical perception of disease probability associated with Bethesda System diagnoses

The degree to which clinical perceptions of Papanicolaou smear sensitivity contribute to patient mismanagement is uncertain. A voluntary, anonymous questionnaire was mailed to 350 obstetricians/gynecologists (OGYNs) and 350 other primary care providers (PCPs) located in Pennsylvania or Ohio. The clinicians estimated the probability of no disease, dysplasia, and invasive carcinoma for 1 of 7 Bethesda System diagnoses. Differences in probability estimates between provider types and between the clinicians and medical literature data were measured. The response rate was 22.7%. Compared with published values, clinicians estimated similar disease probabilities for many diagnoses. However, for some diagnoses, the probability estimates differed considerably from published values (e.g., overestimation of dysplasia and invasive carcinoma for benign diagnoses and underestimation of dysplasia for some dysplasia diagnoses), and such errors could contribute to patient mismanagement. OGYNs generally were more accurate in probability estimates than PCPs. Methods to convey more accurately these diagnostic disease probabilities should be examined.

Implications of prognostic markers in brain tumors

Summarizing the current evidence regarding the usefulness of the previous markers for predicting patient outcome, the most promising proliferation marker for predicting patient outcome in patients with brain tumors appears to be KI-67/MIB-1. Its potential usefulness appears to be greatest (1) for grade II and III astrocytic and oligodendroglial tumors in adults, where it may potentially predict length of survival; (2) for nonpilocytic gliomas in children, where it may also potentially predict survival; and (3) for benign, completely resected meningiomas, where it may potentially predict tumor recurrence. Although MIB-1 shows potential, we do not believe there is evidence yet definitely to consider MIB-1 labeling index a predictor of prognosis in these tumors due to the lack of published prospective studies validating the preliminary findings of multiple investigators who have performed only single-center retrospective studies. We also believe that the exact use of MIB-1 labeling index as an independent prognostic indicator for any type and grade of tumor may be complex, given the fact that all of these brain tumors have multiple independent prognostic factors contributing to patient outcome, many of which are readily available clinical factors. In the present managed care environment, MIB-1 labeling should probably await demonstration that it significantly contributes to the physician's ability accurately to predict patient outcome. The presence of telomerase RNA or telomerase activity appears to correlate with degree of malignancy in multiple types of brain tumors, including gliomas; however, it currently has no use as an independent prognostic indicator of patient outcome. It may instead be a marker for malignant tumor initiation or progression. p53 and EGFR are molecular markers that show promise as prognostic indicators of recurrence-free and overall survival in patients with GBMs, but further prospective studies are needed to confirm the retrospective findings. Postsurgical evaluation of these markers is potentially helpful in planning follow-up and treatment for these patients, those patients having tumors expressing relatively high levels of these markers requiring closer follow-up and, when possible, more aggressive therapies. Despite intensive investigation into the expression of molecules regulating apoptosis in brain tumors, no evidence presently exists to support their usefulness as markers of patient outcome. This also applies to measurements of the apoptotic rate itself in human brain tumors. Our overall impression, therefore, is that despite our great desire to find the Holy Grail of patient prognosis in the measurement of a single molecular marker with a precise cut-off value, one has not been identified ... yet! If we allow ourselves to think in terms of organismal biology, it is not surprising that the attempt directly to correlate one or even five (MIB-1, telomerase, BCL-2, p53, EGFR) gene products with a phenomenon as complex as a patient's long-term survival is unrealistic. More likely, multiple pieces of clinical information (which we already know significantly impact patient outcome in patients with brain tumors) will be considered in conjunction with new, scientifically proved molecular information as it becomes available, allowing us to predict, ever more accurately, a given patient's clinical course and outcome.

The usefulness of pathologists' assistants

The usefulness of pathologists' assistants (PAs) has not been assessed rigorously. Data from a time-motion self-report log generated by an Allegheny General Hospital (Pittsburgh, PA) PA and from the corresponding surgical specimen logs were reviewed to determine the daily distribution of PA time and multiple parameters of practice for gross examination of specimens. Using these data in specific scenarios, PA and non-PA practices were compared. The majority of the PA's time (56.5%) was spent performing gross examination of surgical biopsy specimens. The average cost of gross examination per specimen for a PA and a pathologist was $4.37 and $15.19, respectively. In this practice setting, $91,970.00 is saved per year by the use of a PA. The use of PAs instead of pathologists results in considerable practice cost savings ($560,000 in a practice of 50,000 specimens) or saves pathologists time to perform other necessary functions. PAs are highly useful in an era of cost containment.

Cost-benefit value of microscopic examination of intervertebral discs

OBJECT

Given the virtual absence of histologically detected, clinically unsuspected disease in intervertebral disc specimens, some authors have advocated that histological examination be discontinued. However, the examination of intervertebral disc specimens remains common practice in most pathology laboratories. No cost-benefit analysis of this practice has been made; therefore, the authors' goal in this study was perform such an analysis.

METHODS

Using the University of Iowa surgical pathology database, 1109 patients who had undergone a laminectomy were identified retrospectively. These cases were classified into four categories based on the patients' preoperative clinical diagnosis and final histopathological diagnosis: insignificant clinical diagnosis/insignificant pathological diagnosis (ICIP), significant clinical diagnosis/insignificant pathological diagnosis (SCIP), significant clinical diagnosis/significant pathological diagnosis (SCSP), and insignificant clinical diagnosis/significant pathological diagnosis (ICSP). A significant clinical diagnosis was defined as one other than a benign, noninfectious indication for laminectomy. A significant pathological diagnosis was a diagnosis other than degenerative changes. The cost-benefit value of performing a histological examination in cases with significant or insignificant clinical diagnoses was examined. The cases were classified as: 1068 ICIP, 17 SCIP, 21 SCSP, and three ICSP. On chart review, in all three cases of ICSP an epidural abscess was identified perioperatively and the subsequent histological diagnosis did not affect patient care. The costs per case of identifying a significant pathological diagnosis with a significant and an insignificant clinical diagnosis were $44.79 and $8811, respectively.

CONCLUSIONS

Histological examination of intervertebral disc specimens is cost beneficial only if there is a significant preoperative clinical diagnosis.

Nitric oxide synthase type II expression by different cell types in MHV-JHM encephalitis suggests distinct roles for nitric oxide in acute versus persistent virus infection

Intranasal inoculation with mouse hepatitis virus strain JHM (MHV-JHM) results in acute meningoencephalitis. We found NOS II mRNA expression in brains of acutely infected animals on days 5 through 7 after infection. In situ hybridization and immunohistochemistry demonstrated NOS II message and protein in infiltrating macrophages. Persistent infection with MHV-JHM results in chronic demyelinating encephalomyelitis. NOS II mRNA was detected in persistently infected spinal cords. In situ hybridization and immunohistochemistry showed expression of NOS II in astrocytes in and around demyelinated lesions. These results suggest the role of NO release in acute versus persistent infection with this virus, and its contribution to the resulting pathology, may be different.