Breast cytology - is there still a role?

Evaluation of inadequate, indeterminate, false-negative and false-positive cases in cytological examination for breast cancer according to histological type

Background

We previously investigated the current status of breast cytology cancer screening at seven institutes in our area of southern Fukuoka Prefecture, and found some differences in diagnostic accuracy among the institutions. In the present study, we evaluated the cases involved and noted possible reasons for their original cytological classification as inadequate, indeterminate, false-negative and false-positive according to histological type.

Methods

We evaluated the histological findings in 5693 individuals who underwent cytological examination for breast cancer (including inadequate, indeterminate, false-negative and false-positive cases), to determine the most common histological types and/or features in these settings and the usefulness/limitations of cytological examination for the diagnosis of breast cancer.

Results

Among 1152 cytologically inadequate cases, histology revealed that 75/173 (43.6%) cases were benign, including mastopathy (fibrocystic disease) in 38.6%, fibroadenoma in 24.0% and papilloma in 5.3%. Ninety-five of 173 (54.9%) cases were histologically malignant, with scirrhous growing type, invasive ductal carcinoma (SIDC) being significantly more frequent (49.5%) than papillotubular growing type (Papi-tub) (P < 0.0001), solid-tubular growing type (P = 0.0001) and ductal carcinoma in situ (DCIS) (P = 0.0001). Among 458 indeterminate cases, 54/139 (38.8%) were histologically benign (mastopathy, 30.0%; fibroadenoma, 27.8%; papilloma, 26.0%) and 73/139 (52.5%) were malignant, with SIDC being the most frequent malignant tumor (37.0%). Among 52 false-negative cases, SIDC was significantly more frequent (42.3%) than DCIS (P = 0.0049) and Papi-tub (P = 0.001). There were three false-positive cases, with one each of fibroadenoma, epidermal cyst and papilloma.

Conclusions

The inadequate, indeterminate, false-negative and false-positive cases showed similar histological types, notably SIDC for malignant tumors, and mastopathy, fibroadenoma and papilloma for benign cases. We need to pay particular attention to the collection and assessment of aspirates for these histological types of breast disease. In particular, several inadequate, indeterminate and false-negative cases with samples collected by aspiration were diagnosed as SIDC. These findings should encourage the use of needle biopsy rather than aspiration when this histological type is identified on imaging. Namely, good communication between clinicians and pathological staff, and triple assessment (i.e., clinical, pathological and radiological assessment), are important for accurate diagnosis of aspiration samples.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7349809170055423

Comparison of the accuracy of breast cytological diagnosis at seven institutions in southern Fukuoka Prefecture, Japan

OBJECTIVE

Cytological examination is inexpensive and relatively simple to carry out and deserves utilization in breast cancer screening. We investigated the status of cytological diagnosis at seven facilities in southern Fukuoka Prefecture, Japan.

METHODS

We collected data on the criteria for cytological judgments and status of breast cytological diagnosis at seven different facilities in this region.

RESULTS

Among 5693 individuals who underwent breast cytological examination, analyses were conducted on 1250 individuals (22.0%) in whom cytological diagnoses were confirmed by histological diagnoses. Among these patients, cytological diagnosis had an absolute sensitivity of 71.9%, a specificity of 76.0%, a false-negative value of 6.7% and a false-positive value of 0.08%. At three facilities with relatively large numbers of cases (>300), excluding a facility for specialized breast disease, similar trends of high complete sensitivity (94.3, 95.6 and 97.1%, respectively) and low absolute sensitivity (60.4, 74.8 and 57.2%, respectively) were found. No false-negative or false-positive cases were seen in individual facilities with relatively low numbers of cases (<150).

CONCLUSIONS

The accuracy of cytological diagnosis at the facilities we surveyed was relatively high compared with the goals of assessment of diagnostic accuracy. However, the performance was dependent on the facility type, i.e. number of cases, staff involved and whether it was specialized or not, making the diagnosis specific for this region. We recommend that management of the accuracy of cytological diagnosis be undertaken jointly by multiple facilities to establish systems in Japan that lead to more useful diagnostic tools.

Breast fine needle aspiration cytology: a review of current practice in Australasia

AIMS

To investigate breast fine needle aspiration (FNA) cytology in Australasia, in terms of laboratory demographics, specimens received and quality control (QC).

METHODS

A questionnaire was sent to all laboratories enrolled in the FNA module of the Royal College of Pathologists of Australasia Cytopathology Quality Assurance Program (QAP), requesting information about specimens received in a 3-month period in 2001 and in 2008.

RESULTS

Responses were received from 81/180 laboratories in 2001 and from 94/200 in 2008. The mean number of cases per 3 months was 137 in 2001 and 141 in 2008 and for the 42 laboratories responding on both occasions, the mean number of cases declined from 191 to 149 (P=0.001). The mean percentage of malignant cases was 11.7% in 2001 and 10.5% in 2008 and the mean percentages of unsatisfactory rates were 21.7% and 25.2%, respectively; 43.2% of laboratories in 2001 and 40.4% in 2008 reported fewer than 50 cases for the 3-month period. The unsatisfactory rate was inversely proportional to the number of cases received. Most QC (69.1% in 2001, 71.3% in 2008) was carried out by correlation with any later histology. With no histology available, 35.8% of laboratories in 2001 and 48.9% in 2008 did no further follow-up. Follow-up of all diagnostic categories increased from 30.9% in 2001 to 44% in 2008.

CONCLUSIONS

Breast FNA cytology is still actively undertaken in Australasia, but numbers have declined. Unsatisfactory rates have reached the Australian recommended upper limit and are inversely proportional to the total number of cases received. Overall QC measures are unchanged and consideration of a review of breast FNA guidelines is suggested.

Fine-needle aspiration cytology of the breast

Fine-needle aspiration cytology (FNAC) is an established, highly accurate, and cost-effective method for diagnosing lesions in different organs, including the breast. The method is minimally invasive without unwanted side effects. FNAC forms part of the triple assessment of breast lesions. Despite some shortcomings of the reporting categories, FNAC as part of the triple assessment has proved its value in describing the findings most accurately. The diagnostic impact depends on experience of the operator, quality of preparation, and diagnostic skills of the cytopathologist. The highest accuracy is achieved at centers with a multidisciplinary approach. FNAC is often palpation guided from palpable breast masses, whereas ultrasonography guidance is more widely used on nonpalpable lesions. Inadequate sampling with FNAC is particularly seen in collagenous lesions and in submitted specimens sampled by physicians lacking experience with the FNAC procedure. A diagnostic biopsy is recommended when FNAC provides scant material. FNAC is considered to be a safe method for screening purposes, although moderately less sensitive than core needle biopsy. FNAC is most accurate when experienced cytopathologists are available to assess the adequacy of the aspirated material and advise on additional aspirations for ancillary tests when needed.

Diagnostic accuracy of fine-needle aspiration cytology in histological grade 1 breast carcinomas: are we good enough?

BACKGROUND

Fine-needle aspiration cytology (FNAC) of both palpable and non-palpable breast carcinomas has a high accuracy and sensitivity in dedicated centres. It is generally thought that low-grade carcinomas have a distinctly lower sensitivity due to discrete cellular atypia that may be difficult to appreciate. Grade 1 carcinomas make up about 45% of screening-detected breast carcinomas and about 20% of symptomatic breast cancers. The aim of this study was to evaluate the diagnostic sensitivity of grade 1 carcinomas and identify the critical features in the cytological diagnostic work-up of these tumours.

METHODS

There were FNAC smears from 494 histologically confirmed grade 1 carcinomas diagnosed during 1996-2004. The cytological diagnoses were compared with the histology.

RESULTS

A definitive malignant diagnosis (absolute sensitivity) was given in 382 cases (77.3%). Equivocal or suspicious diagnoses were given in 75 (15.2%), benign or probably benign (false negative) in 24 (4.8%). Thirteen cases (2.6%) were unsatisfactory. Complete sensitivity was 92.7%. Invasive ductal carcinomas comprised 81.3% of all cases; absolute sensitivity for these was 80.9%. Invasive lobular and tubular carcinomas comprised 7.3% and 5.9% of cases, respectively; absolute sensitivity for these diagnosis was 50.0% and 57.1%, respectively, significantly lower than for other subtypes (P <or= 0.0001) whereas the difference for complete sensitivity was less but still significant (P = 0.017). Absolute and complete sensitivities were lower for tumours less than 1 cm size compared with more than 1 cm (P <or= 0.00001).

CONCLUSION

Preoperative FNAC diagnosis of grade 1 breast carcinoma has a high sensitivity, especially in ductal carcinomas. Invasive lobular and tubular carcinomas were less likely to receive a definite preoperative diagnosis. The main reason for not reaching a definitive malignant diagnosis was sampling error due to small tumours less than 1 cm in diameter, irrespective of tumour subtype.

Fine needle biopsy cytology of breast lesions: a review of interpretative difficulties

Screening mammography and greater community awareness of breast carcinoma have led to an increase in fine needle biopsies of the breast. As a consequence, a wide variety of cytologic patterns have been encountered and studied in benign, proliferative, and malignant breast lesions. We review the main reasons for diagnostic difficulties in breast cytology, the situations in which either a false positive or a false negative diagnosis is possible, as well as conditions whose incorrect typing can lead to inappropriate management.