Undetected invasive lobular carcinoma of the breast: review of false-negative smears

Fine-needle aspiration and core biopsy in the diagnosis of breast lesions: A comparison and review of the literature

In recent times, the diagnosis of breast lesions has mostly become dependent on core needle biopsies (CNBs) with a gradual reduction in the rate of performing fine-needle aspiration cytology (FNAC). Both the procedures have their pros and cons and outsmart each other taking into account different parameters. Both the methods are found to be fraught with loopholes, taking into account different performance indices, diagnostic accuracy and concordance, patient benefit, and cost-effectiveness. Unlike the popular belief of an absolute superiority of CNB over FNAC, the literature review does not reveal a very distinct demarcation in many aspects. We recommend judicious use of these diagnostic modalities in resource-limited settings and screening programs taking into account parameters such as palpability and availability of an experienced cytopathologist.

Grey zone lesions of breast: Potential areas of error in cytology

Fine-needle aspiration cytology (FNAC) of the breast is a rapid, cost-effective, and sensitive procedure to diagnose breast lesions, and was widely employed to diagnose breast lesions in the past. However, in recent times, core needle biopsy of the breast is gaining popularity and acceptability, although FNAC still looms large. There are some intrinsic disadvantages to FNAC, of which the most important is probably difficulty in classification of a significant percentage of breast lesions. Such lesions are usually denoted by the rubric “grey zone lesions of the breast.” This article attempts to review these grey zone lesions and highlight the difficulties in diagnosing them.

Rapid cell blocks improve accuracy of breast FNAs beyond that provided by conventional cell blocks regardless of immediate adequacy evaluation

A new "rapid cell block" technique (RCB; the predecessor of Cellienttrade mark Automated Cell Block System) is efficient at recovering sparse material. We previously found that RCBs of breast fine-needle aspirations (FNAs) frequently allow histologic classification of problematic ductal proliferative lesions. Previous studies that did not emphasize cell blocks found that on-site evaluation (OSE) of breast FNAs improves diagnosis. The purpose of this study was to determine if RCB could replace the utility of OSE of breast FNAs. The study included 604 consecutive ultrasound-guided noncyst breast FNAs composed of three cohorts based on the presence or absence of immediate adequacy assessment, conventional (collodion bag) cell blocks (CCB), and RCB. The cohort with OSE together with CCB did not perform as well as the cohort without OSE but with RCB. In a third cohort, performance characteristics of RCBs and CCBs were compared in an independent review by two cytopathologists blinded to the final cytology and follow-up histology diagnosis. By itself, the RCB histologic section was diagnostic 97% of the time, and it provided a diagnostic accuracy superior to CCB by itself and comparable to that provided by the combination of the smears with CCB. Highest accuracy was obtained by combining smears/monolayer preparations and RCB. Replacing OSE with RCBs provided substantial cost savings and savings of time for cytopathologists, radiologists, and their assistants.

Cytologic diagnosis of lobular carcinoma of the breast: experience with 555 patients in the Rene Huguenin Cancer Center

BACKGROUND

Fine-needle aspiration generally produces results that are not as good for lobular carcinoma as the results for ductal carcinoma of the breast. In this study, the authors evaluated their team's performance in cytologic diagnosis of lobular carcinoma over 11 years and analyzed the reasons for diagnostic failure.

METHODS

Cytologic findings were analyzed in 555 consecutive fine-needle cytopuncture specimens from women with palpable, invasive lobular carcinoma of the breast. The authors also examined the influence of the cytologist's experience, the clinical tumor size, the histologic subtype, and the histologic grade on diagnostic performance. All negative samples were re-examined, along with all samples that had been obtained during the last year of the study, to refine the morphologic description of lobular carcinoma.

RESULTS

Malignancy was diagnosed in 68.8% of specimens overall. The individual pathologists diagnosed malignancy in from 44.4% to 81.1% of specimens, depending on their experience. Diagnostic performance was correlated with clinical tumor size, histologic grade, and histologic subtype, and correct diagnoses were significantly more frequent in pleomorphic subtypes than in "classic" types. Re-examination of all 32 negative specimens reduced the false-negative rate from 5.8% to 3.8%.

CONCLUSIONS

Despite the pitfalls associated with lobular carcinoma of the breast, fine-needle cytopuncture remains a useful diagnostic tool before treatment. Failures can be reduced through experience and by better knowledge of cytologic features.

Cytomorphology of Common Malignant Tumors of the Breast

A definitive cytologic diagnosis of breast cancer is usually possible when using the six major criteria of malignancy (cellularity, dyshesion, monomorphism, anisonucleosis, irregular nuclear membranes, prominent nucleoli) as part of the triple test. Carcinomas of special type have unique clinical and cytologic features that pathologists need to consider, because these may confuse interpretation. Complete subtyping of carcinomas may not always be possible by fine needle aspiration. Diagnostic accuracy for breast carcinoma is excellent. False-negative diagnoses are infrequent and chiefly due to sampling issues. False-positive diagnoses are extremely rare. Uniform report terminology should be used to ensure that diagnostic information is conveyed appropriately and consistently to guide the next diagnostic or treatment step.

Anatomic Pathology Databases and Patient Safety

Context.—The utility of anatomic pathology discrepancies has not been rigorously studied.

Objective.—To outline how databases may be used to study anatomic pathology patient safety.

Design.—The Agency for Healthcare Research and Quality funded the creation of a national anatomic pathology errors database to establish benchmarks for error frequency. The database is used to track more frequent errors and errors that result in more serious harm, in order to design quality improvement interventions intended to reduce these types of errors. In the first year of funding, 4 institutions (University of Pittsburgh, Henry Ford Hospital, University of Iowa, and Western Pennsylvania Hospital) reported cytologic-histologic correlation error data after standardizing correlation methods. Root cause analysis was performed to determine sources of error, and error reduction plans were implemented.

Participants.—Four institutions self-reported anatomic pathology error data.

Main Outcome Measures.—Frequency of cytologic-histologic correlation error, case type, cause of error (sampling or interpretation), and effect of error on patient outcome (ie, no harm, near miss, and harm).

Results.—The institutional gynecologic cytologic-histologic correlation error frequency ranged from 0.17% to 0.63%, using the denominator of all Papanicolaou tests. Based on the nongynecologic cytologic-histologic correlation data, the specimen sites with the highest discrepancy frequency (by project site) were lung (ranging from 16.5% to 62.3% of all errors) and urinary bladder (ranging from 4.4% to 25.0%). Most errors detected by the gynecologic cytologic-histologic correlation process were no-harm events (ranging from 10.7% to 43.2% by project site). Root cause analysis identified sources of error on both the clinical and pathology sides of the process, and error intervention programs are currently being implemented to improve patient safety.

Conclusions.—A multi-institutional anatomic pathology error database may be used to benchmark practices and target specific high-frequency errors or errors with high clinical impact. These error reduction programs have national import.

Improving patient safety by examining pathology errors

A considerable void exists in the information available regarding anatomic pathology diagnostic errors and their impact on clinical outcomes. To fill this void and improve patient safety, four institutional pathology departments (University of Pittsburgh, Western Pennsylvania Hospital, University of Iowa Hospitals and Clinics, and Henry Ford Hospital System) have proposed the development of a voluntary, Web-based, multi-institutional database for the collection and analysis of diagnostic errors. These institutions intend to use these data proactively to implement internal changes in pathology practice and to measure the effect of such changes on errors and clinical outcomes. They believe that the successful implementation of this project will result in the study of other types of diagnostic pathology error and the expansion to national participation. The project will involve the collection of multi-institutional anatomic pathology diagnostic errors in a large database that will facilitate a more detailed analysis of these errors, including their effect on patient outcomes. Participating institutions will perform root cause analysis for diagnostic errors and plan and execute appropriate process changes aimed at error reduction. The success of these interventions will be tracked through analysis of postintervention error data collected in the database. Based on their preliminary studies, these institutions proposed the following specific aims: Specific aim #1: To use a Web-based database to collect diagnostic errors detected by cytologic histologic correlation and by second-pathologist review of conference cases. Specific aim #2: To analyze the collected error data quantitatively and generate quality performance reports that are useful for institutional quality improvement programs. Specific aim #3: To plan and implement interventions to reduce errors and improve clinical outcomes, based on information derived from root cause analysis of diagnostic errors. Specific aim #4: To assess the success of implemented interventions by quantitative measure of postinterventional errors and clinical outcomes and by qualitative assessment by project participants. Funding for this project was approved by the Agency for Health Care Research and Quality in September 2002, and data collection and analysis are ongoing. Over 5000 errors have been collected in the database, and the clinical outcomes of these errors have been tracked. At a national meeting in November 2003, root cause analysis was performed to determine causes of errors. The findings of these root cause analyses have been presented at national pathology meetings and are currently being published.

Interobserver agreement of a probabilistic approach to reporting breast fine-needle aspirations on ThinPrep®

We have previously demonstrated the accuracy and reproducibility of a probabilistic/categorical approach for reporting breast fine-needle aspiration (FNA). However, the interobserver agreement in the application of this approach has not been assessed. Twenty breast FNA cases (each on one ThinPrep slide) were pulled from the cytology files of Beth Israel Deaconess Medical Center. The cases included benign epithelial proliferative lesions (6), DCIS (4), and infiltrating carcinoma (10), as shown by subsequent histology. Six pathologists with 14-25 yr of experience in interpreting breast FNA and 0-8 yr of experience with ThinPrep preparations rendered diagnoses according to the probabilistic approach. The kappa statistic for the unremarkable/proliferative, atypical, suspicious, and positive categories were 0.64, 0.08, 0.43, and 0.75, respectively (P < 0.001 for all except for the atypical category [P = 0.09]). Spearman's rho correlating the individual pathologist's diagnosis and the histologic diagnosis ranged from 0.51 (P = 0.02) to 0.78 (P < 0.0001). This was not correlated with the pathologists' years of experience interpreting breast FNA (P = 1.0) or with their years using ThinPrep preparations for breast FNA (P = 0.96). In conclusion, the interobserver agreement was excellent for the positive category in the probabilistic approach, poor for the atypical category, and fair to good for the other categories. The specific level of experience interpreting breast FNA or using ThinPrep among experienced pathologists did not seem to influence their accuracy in reporting the cases in our study.

How stereotactic core-needle biopsy affected breast fine-needle aspiration utilization: An 11-year institutional review

To determine the effect of stereotactic core-needle biopsy (SCNB) on the utilization of breast fine-needle aspirate (FNA) biopsy, we retrospectively reviewed 1,568 cases of breast FNAs that were obtained from 1,188 patients between the years 1990 and 2000. There were 378 positive and atypical cases and 497 negative and unsatisfactory cases in the pre-SCNB group (between 1990 and 1996; 7 years); and 225 positive and atypical cases and 468 negative and unsatisfactory cases in the post-SCNB group (between 1997 and 2000; 4 years). The average number of cases per year in the pre- and post-SCNB groups was 125 and 173, respectively. While the average positive/atypical cases per year in both groups remained relatively constant, the average negative/unsatisfactory cases per year were significantly increased in the post-SCNB group (117 in the post-SCNB vs. 71 in the pre-SCNB). The increase in this group was due to a true increase in the negative diagnoses, since unsatisfactory rate decreased in the post-SCNB group (12.6% in the post-SCNB vs. 9.3% in the pre-SCNB). The sensitivity, specificity, positive predictive value, and negative predictive value were 90%, 79%, 92%, and 82% in the pre-SCNB group and 93%, 86%, 91%, and 90% for the post-SCNB group, respectively. In conclusion, the implementation of SCNB did not result in a decrease in the total number of breast FNAs; however, the distribution of cases changed. FNA is increasingly used to complete the triple test in clinically and radiographically negative cases.

Cytologic diagnosis of invasive lobular carcinoma: Factors associated with negative and equivocal diagnoses

Fine-needle aspiration biopsy (FNAB) of invasive lobular carcinoma (ILC) is associated with notoriously high rates of false negative and equivocal diagnoses. To identify causative factors, we reviewed the cytologic features of presurgical FNAB smears of ILC and correlated the cytologic findings with the number of passes, tumor size, mammographic findings, and the histologic characteristics of the tumor. Smear cellularity, presence of single intact epithelial cells, nuclear size, nuclear atypia, palpability of the tumor, and histologic type of ILC (classic versus nonclassic) were statistically significant in establishing an unequivocally positive diagnosis. We also found that the cytologic cellularity of the lesion does not reflect the actual cellularity of the tumor but instead is an indicator of the architectural arrangement of the neoplastic cells; tumors that form epithelial cell groups, such as in nonclassic ILC, tend to yield more cellular aspirates that are diagnostic for carcinoma. In contrast, classic ILC, in which single neoplastic cells are embedded in fibrous stroma, is more likely to yield a paucicellular smear with subtle atypia and rare single intact epithelial cells. As such, an inconclusive diagnosis in a certain percentage of classic ILC cases may be unavoidable.