Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling

Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation.     

Usefulness of AgNOR technique and CEA expression in atypical metaplastic cells from cervical smears

OBJECTIVE: To evaluate the proliferating capacity of atypical metaplastic cells in cervical smears by AgNOR technique and image analysis and investigate the probable relation with squamous intraepithelial lesions (SIL) using immunocytochemical assay for carcinoembryonic antigen (CEA). STUDY DESIGN: Eight cervical smears were stained with Papanicolaou stain for diagnosis of atypical metaplastic cells. After removal of the stain the smears were processed with a silver colloidal solution and the AgNOR area determined by image cytometry. Differences in the mean AgNOR protein area between reactive metaplastic cells and controls were tested by Student's t test. The CEA was investigated by immunocytochemical staining in smears with atypical metaplastic cells and smears from high-grade squamous intraepithelial lesions (HSIL). RESULTS: The mean AgNOR areas from atypical metaplastic cells (4.55, 6.66, 4.68, 5.30, 4.97, 6.20, 6.28, and 7.35) were significantly greater those that of intermediate metaplastic cells and cells from low-grade squamous intraepithelial lesions (LSIL) (0.77, 0.99, and 0.82, respectively). The atypical metaplastic cells showed values of mean AgNOR area intermediate between that of basal cells (3.28) and HSIL cells (7.73) or neoplastic cells (16.12). The CEA was strongly expressed by the atypical metaplastic cells. CONCLUSION: The expression of CEA in the atypical metaplastic cells underlies the probable relation to SIL. Although the organizer region areas raised high values, it would be necessary to use a greater number of cases to define whether the AgNOR area is indicative of the proliferative activity of the atypical metaplastic cells.     

ASCUS, mature metaplastic type. Cytologic diagnosis and follow-up

OBJECTIVE: To study the cytologic criteria for follow-up of mature metaplastic cells within the atypical squamous cells of undetermined significance (ASCUS) category. STUDY DESIGN: Squamous epithelial abnormalities between January 1994 and June 1997 at our institution totaled 2,632 and included squamous carcinoma (1), high grade squamous intraepithelial lesions (278), low grade squamous intraepithelial lesions (875) and ASCUS (1,478). From the ASCUS group, 134 (9.06%) were metaplastic; 89 were selected for review. Criteria for case selection were follow-up with tissue biopsy or at least two Pap smears and no previous epithelial abnormality. Patients ranged from 27 to 70 years of age. Parameters tabulated included number of abnormal cells per slide, their architecture, cell size, shape, cytoplasmic hue and texture, nuclear size and contour, chromatin pattern and nucleoli. Additionally, specimens were reviewed for hormonal status and inflammation. The findings were correlated with follow-up data. RESULTS: Cells generally appeared single or in loose, monolayered sheets of three to seven cells per group. The cells were well demarcated, polygonal or oval and ranged from 11 to 30 microns with cyanophilic or eosinophilic thickened cytoplasm. The round to oval nuclei with slight irregularity showed a minimally increased nuclear/cytoplasmic ratio with stippled chromatin. Upon review, 69 smears were confirmed as ASCUS-M. Follow-up revealed 42 with benign findings, 9 with persistent ASCUS/ASCUS-M and 18 with low grade squamous intraepithelial lesions. CONCLUSION: In mature metaplastic cells with minimal atypia in patients with no previous or concurrent dysplasia, the follow-up details were similar to those described for ASCUS-superficial/immediate squamous cells. These patients could be followed conservatively.     

Clinical significance of atypical glandular cells of undetermined significance. A follow-up study from an academic medical center

OBJECTIVE: To determine the rate of atypical glandular cells of undetermined significance (AGUS) and the incidence of subsequent clinically significant lesions. STUDY DESIGN: A computer-based search of our cytology laboratory files was performed for cervicovaginal smears diagnosed as AGUS from January 1996 to December 1996. RESULTS: In 43,456 cervicovaginal smears examined during the 12-month period, AGUS was reported in 222 (0.5%) cases, with follow-up in 191 (86.0%) (133 [59.9%] biopsies and 58 [26.1%] repeat cervicovaginal smears). Among the patients with repeat cervicovaginal smears, 1 (1.7%) had a high grade squamous intraepithelial lesion, and 10 (17.2%) had persistent AGUS/atypical squamous cells of undetermined significance; the remainder were within normal limits. Thirty-three (24.8%) patients had preneoplastic or neoplastic, squamous or glandular lesions on biopsy (8 [6.0%] cervical intraepithelial neoplasia [CIN] 1, 18 [13.5%] CIN 2/3 and 7 [5.3%] endometrial adenocarcinomas). Half the patients with CIN 2/3 also had evidence of endocervical gland involvement. Squamous lesions were seen more commonly in premenopausal women, while glandular lesions were noted predominantly in postmenopausal women. Patients with a prior abnormal gynecologic history or a concomitant diagnosis of squamous intraepithelial lesion (SIL) had a higher incidence of significant lesions on subsequent biopsy. CONCLUSION: Our incidence of AGUS was 0.5%, similar to that in other published reports. AGUS is associated with a significant number of squamous or glandular, premalignant or malignant lesions. A majority of these lesions are high grade SIL, often with endocervical gland involvement. A small but significant number of patients had a glandular malignancy. Our results justify close and persistent follow-up for patients with a diagnosis of AGUS on cervicovaginal smears.     

Clinical impact of atypical squamous cells of undetermined significance. A cytohistologic comparison

OBJECTIVE: To assess the percentage of squamous intraepithelial lesions (SILs) in the atypical squamous cells of undetermined significance (ASCUS) cytologic diagnosis. STUDY DESIGN: From January 1994 to December 1995, 421 cervical Pap smears with a diagnosis of ASCUS were followed with cervical biopsies within three months. The ASCUS cytologic diagnosis was correlated with the histologic findings and stratified according to age group, previous abnormal history and cell type of ASCUS (squamoid vs. metaplastic). RESULTS: Histologic diagnosis showed that of ASCUS diagnoses, 13% were normal, 34% were reactive, 4.8% were atypical, 43% were low grade SIL, 4% were high grade SIL, 1% were carcinoma in situ, and none were invasive lesions. The patients in the youngest group, up to 25 years, demonstrated the highest percentage of SIL. Patients with a previous abnormal gynecologic history showed a higher percentage of SIL than those without an abnormal history. SILs were observed in 51.5% of squamoid ASCUS and 36.5% of metaplastic ASCUS. CONCLUSION: Forty-eight percent of females having an ASCUS diagnosis on Pap smears had SIL and thus a preneoplastic lesion. The highest percentage of SIL was found in females 25 years and younger. Our findings suggest that an ASCUS diagnosis warrants ongoing follow-up.     

Intraobserver and interobserver variability in the quality assessment of cervical smears

Intraobserver and interobserver variability in assessing the quality of cervical smears, as measured by the presence or absence of endocervical columnar cells and squamous metaplastic cells, was evaluated. In total, 180 cervical smears representing the most important cytologic diagnoses were anonymously rescreened twice by 19 observers with an interval of six months. An absence of endocervical columnar cells was proven to correlate with a high percentage of false-negative diagnoses. Intraobserver agreement on the presence or absence of endocervical columnar cells was 85.7% between the two screenings. A predictive value of 57.7% was found for a negative scoring (absence of these cells) while the predictive value of a positive scoring (presence of endocervical cells) was 87.3%. Of the observer scorings, 83.9% concurred with the final diagnosis; there was no significant correlation between that concurrence and the number of years of experience in cytopathology of the observer. For squamous and squamous metaplastic cells in the cervical smear the predictive value of a negative scoring (absence) was only 20.6%. Compared to the final diagnosis, 69.5% of these scorings matched. A significant and relatively high correlation with the experience of the observer was found for the scoring for the presence of metaplastic cells. Even though the predictive values of these quality scorings were relatively low a significantly higher risk for false diagnoses was established when negative scorings were given. It is therefore advisable to have smears with negative scorings for endocervical columnar cells and squamous metaplastic cells always rescreened by another observer.     

Papanicolaou smears without endocervical cells. Are they inadequate?

The retrieval of columnar endocervical cells from the squamocolumnar junction has generally been considered to be a measure of the adequacy of a Papanicolaou smear; this implies that, if endocervical cells are absent from the smear, the examination for cervical cancer is less than optimal and should be repeated. A study was undertaken to determine if women with serial Papanicolaou smears without endocervical cells showed an increased rate of development of cervical atypia in subsequent smears. The smears of 18,914 women were evaluated for the presence or absence of endocervical cells and for the subsequent development of an abnormal smear over a four-year study period. No differences were found in the rates of atypia between women with and those without endocervical cells on serial Papanicolaou smears. Women with prior Papanicolaou smears without endocervical cells were much more likely to have a subsequent Papanicolaou smear without endocervical cells. Although no difference was found in the incidence of cervical atypia in the two groups during this short study period, these results should be considered to be preliminary.     

Influence of endocervical status on the cytologic prediction of cervical intraepithelial neoplasia.

A case-control analysis of the endocervical status of smears that preceded a histologic diagnosis of cervical intraepithelial neoplasia (CIN) showed that smears which correctly predicted CIN were significantly more likely to include metaplastic cells than were smears reported to be negative. There was no significant difference between the smears with respect to the presence of columnar cells. A high level of agreement was apparent between scientists in determining both columnar and metaplastic cell status. A discussion of the definition, role and potential impact of endocervical status in the prevention of cervical cancer is presented.     

Interobserver and intraobserver variability in the cytologic diagnosis of normal and abnormal metaplastic squamous cells in pap smears

OBJECTIVE: Interoberver variability has important implications for patient care, diagnostic error and medical litigation. In the management of any cervical epithelial abnormality, its biologic significance as well as diagnostic reproducibility is very important. Interobserver variability has not been measured adequately for metaplastic squamous lesions. We analyzed interobserver and intraobserver variability and diagnostic accuracy in the diagnosis of dysplastic metaplastic cells. STUDY DESIGN: Sixty Pap smears from patients with abnormalities of metaplastic squamous cells of varying severity were selected from the files of Lankenau Hospital, Wynnewood, Pennsylvania, U.S.A., diagnosed between 1990 and 1996. These were reviewed by four observers with different levels of cytology experience. Each of the observers blindly and independently reviewed all Pap smears. Tabulated results were analyzed to determine interobserver and intraobserver variability and diagnostic accuracy. RESULTS: Statistically significant interobserver reproducibility was found between both inexperienced observers as well as between observers 1 (experienced) and 3 (inexperienced) and between observers 2 (experienced) and 4 (inexperienced). The observed degree of agreement between both experienced observers (1 and 2) reflected random rating rather than reproducibility. There was no difference in interobserver reproducibility in low vs. high grade lesions. Intraobserver reproducibility had no significant correlation with experience of the observer. The sensitivity ranged from 0.69 to 0.97 (mean, 0.79), while the specificity ranged from 0.09 to 0.46 (mean, 0.30). Mean diagnostic accuracy was better in benign and low grade squamous intraepithelial lesions in comparison to high grade squamous intraepithelial lesions. CONCLUSION: There was good interobserver agreement in classifying squamous metaplastic lesions. The agreement did not correlate with grade of dysplasia or experience of the cytopathologists. These findings should be considered in making treatment, quality assurance and legal decisions. A larger study is indicated to study interobserver and intraobserver variability and define cytologic criteria for lesions of metaplastic squamous cells.     

Significance of AGUS Pap smears in pregnant and postpartum women

OBJECTIVE: To study the clinical significance of atypical glandular cells of undertermined significance (AGUS) in pregnant and postpartum women. STUDY DESIGN: We evaluated 35 women who were pregnant (30) or within three months postpartum (5) and had a cytologic diagnosis of AGUS. Twenty-seven (77%) patients had follow-up: 17 (63%) patients underwent colposcopic examination and biopsy, and 10 (37%) had repeat Pap smears. Eight patients were lost to follow-up. RESULTS: Five (29.4%) patients had a squamous intraepithelial lesion (SIL), including three high grade and two low grade, on subsequent biopsy. The remaining (70.6%) patients had benign pathology, which included 5 chronic cervicitis, 4 endocervical and/or endometrial polyps, 2 Arias-Stella reaction and 1 microglandular hyperplasia. Among the patients with repeat Pap smears, two had persistent AGUS/atypical squamous cells of undetermined significance, the remaining cases were within normal limits. CONCLUSION: Pregnancy-related changes may present with glandular atypia. In addition, about one-third of pregnant and postpartum women with a diagnosis of AGUS had SIL on subsequent biopsy; that rate is similar to that in nonpregnant women. Therefore, pregnant women with a cytologic diagnosis of AGUS should be followed closely.     

Measurement of subvisual changes in cervical squamous metaplastic cells for detecting abnormality.

Quantitative measures of visually normal squamous metaplastic cells exfoliated from the uterine cervix were obtained to test the hypothesis that these cells, like intermediate squamous and endocervical columnar cells, show subvisual evidence of atypia in cases of bonafide squamous intraepithelial neoplasia. The cells identified as squamous metaplastic were obtained from 14 abnormal (dysplastic) and 9 diagnostically negative cases. Although the cell populations so grouped showed no statistically significant differences in overall cell size, nuclear area or nuclear/cytoplasmic ratios, there were significant differences in nuclear and cytoplasmic densitometric features and in nuclear texture features. A combination of three features (nuclear density, texture and cytoplasmic density) permitted 76% of the cells to be categorized correctly as originating in normal versus abnormal slides. It is concluded that selected quantitative features of exfoliated metaplastic cell populations may contribute to improved diagnostic accuracy in automated screening for cervical abnormalities.     

Cellular Differences Between True Negative and False Negative Papanicolaou Smears

A matched case-control study of 123 false negative Papanicolaou smears and 488 true negative Papanicolaou smears was undertaken to determine the association between the types of cells present on the smear and the correctness of the cytology report. the false negative slides were significantly more likely to include endocervical columnar cells than the true negative slides (odds ratio 1.90, 95% confidence interval (CI) 1.21–3.01). No statistically significant difference in metaplastic cell status was evident (odds ratio 1.48, 95% CI 0.95–2.30). When considered together, metaplastic and/or columnar cells were significantly more likely to be present in false negative smears than in true negative smears (odds ratio 1.87, 95% CI 1.13–3.08). the implications of these findings for improving the accuracy of cervical cytology for the detection of precancerous lesions are discussed.     

Evaluation of PAPNET-assisted cervical rescreening

Evaluation of PAPNET-assisted cervical rescreening
We have compared the results of targeted manual rescreening of 1211 randomly selected smears with the results of PAPNET-assisted rescreening of 1613 cervical smears, containing at least 6.3% low-grade squamous intraepithelial lesion (SIL). PAPNET diagnosis and the targeted rescreening diagnosis were compared with the initial report, issued on the corresponding smear. Reproducibility scores for inadequacy, presence of endocervical and endometrial cells, specific infections and squamous cell abnormalities were determined. The reproducibility scores for the diagnosis of inadequate smears and specific infections were lower with the PAPNET-assisted rescreening. The detection of squamous cell abnormalities was excellent for both methods (>0.95), with a higher detection rate for false-negative smears with the PAPNET testing system.     

Atypical squamous cells of undetermined significance in women over 55. Comparison with the general population and implications for management.

OBJECTIVE: To determine the significance of atypical squamous cells of undetermined significance (ASCUS) in patients 55 years or older. STUDY DESIGN: From January 1994, to January 1997, 8,175 cervicovaginal smears were obtained from patients 55 years or older (mean age, 64.8; range, 56-84) at University Hospitals of Cleveland. Ninety-six of these patients were diagnosed with ASCUS only or ASCUS with a qualifying statement on the smear. Patient records, follow-up cervicovaginal smears and biopsies were reviewed for a period of one to four years following the diagnosis of ASCUS. RESULTS: The incidence of ASCUS only or ASCUS with a qualifying statement for patients 55 years or older was 1.8%. The ASCUS:SIL ratio was 2.6:1. An estrogen stimulation test was recommended in two cases. Women older than 55 with ASCUS were three times more likely to be receiving hormonal replacement therapy than similar-aged women with normal cervicovaginal smears. Follow-up cervicovaginal smears or biopsies were obtained on 93 (80 cervicovaginal smears, 13 biopsies). The results were the following: LSIL (13), squamous carcinoma in situ (1) and ASCUS (53); the remainder of the cases were normal. In the patients who received a second diagnosis of ASCUS, follow-up cervi covaginal smears or biopsies revealed low grade dysplasia in six. CONCLUSION: Although the incidence of ASCUS and the frequency of underlying dysplasia is lower in postmenopausal women than the general population, there is still a real risk that a postmenopausal woman with ASCUS has underlying intraepithelial neoplasia. Therefore, these patients should be managed as is the general population.     

The detection of endocervical gland involvement by high grade squamous intraepithelial lesions in smears prepared from endocervical brush specimens

The cytologic features of squamous cell carcinoma in situ with endocervical gland involvement have been described in cervical smears. We evaluated the presence of two types of cellular fragments in 43 cervical smears of high grade squamous intraepithelial lesions (HGSIL) to assess their ability to predict glandular involvement by HGSIL in subsequent cone biopsies. an endocervical brush was used to obtain all endocervical specimens. of 16 cases without glandular involvement, fragments were present in 13 smears. of 27 cases with glandular involvement, fragments were absent in 11 smears. No statistical association was identified between the presence of abnormal cellular fragments on cervical smears of HGSIL and endocervical gland involvement on cone biopsies.     

Intraobserver and interobserver variability in the diagnosis of epithelial abnormalities in cervical smears

In a study of variability in the diagnosis of epithelial abnormalities, cervical smears with abnormalities of different severity were rescreened twice by 19 observers with an interval of six months. The observers focused on grading atypicality of squamous, squamous metaplastic and endocervical columnar epithelial cells; their results were compared (1) for the two screenings to assess intraobserver variability and (2) to "review" (final) diagnoses to assess interobserver variability. When the same observer rescreened a smear, 83.3% of the diagnoses did not differ more than one grade between two screenings; however, average intraobserver variability differed considerably for individual observers. The intraobserver variability was only slightly (not significantly) influenced by the years of experience in cytopathology of the observers. Intraobserver variability proved to be an important factor in incorrect diagnoses: 49.1% of the smears with false-negative and 52.9% with false-positive diagnoses at the first rescreening were correctly assessed at the second rescreening. Of all diagnoses made at rescreening, 80.9% were in agreement with the review diagnosis. The interobserver variability also showed considerable differences between observers; however, there was a strong influence of the experience of the observer on the interobserver variability. Atypicality grading of endocervical columnar epithelium by the observers showed a low correlation with the review diagnoses. The relatively low accuracy in the evaluation of this kind of epithelial abnormality is likely to be attributable to the low incidence of abnormal changes of endocervical columnar epithelium. The results of this study point to intraobserver variability as the main cause of false diagnoses. When wrongly diagnosed, severe epithelial abnormalities are more often underestimated than completely overlooked. Apart from training in cytopathology, the establishment of laboratory protocols for multiple screening of even minor abnormalities seem to be the most effective means of reducing the number of false diagnoses.     

Atypical squamous cells and low‐grade squamous intraepithelial lesion in cervical cytology: cytohistological correlation and implication for management in a low‐resource setting

N. Gupta, R. Srinivasan, R. Nijhawan, A. Rajwanshi, P. Dey, V. Suri and L. Dhaliwal Atypical squamous cells and low‐grade squamous intraepithelial lesion in cervical cytology: cytohistological correlation and implication for management in a low‐resource setting Objectives: To perform an audit of all cervical smears reported as atypical squamous cells (ASC) and low‐grade squamous intraepithelial lesion (LSIL) as in the Bethesda system (TBS) 2001, and determine their histological follow‐up and outcome when available, in order to define the threshold for colposcopic referral. Material and methods: A total of 25 203 cervical smears were screened over a period of 3 years (January 2006 – December 2008) and all ASC and LSIL smears were reviewed with the corresponding histological follow‐up. All cervical intraepithelial neoplasia (CIN) grade 2 lesions and above (CIN2+) were considered as clinically significant lesions for analysis. Results: Out of 25 203 cervical smears, 424 (1.7%) were reported as ASC and 113 (0.4%) as LSIL. Additionally, three were reported as atypical cells, not otherwise specified. The ASC : SIL ratio was 2.18 : 1. Follow‐up histology was available in 153 (36.8%) of the ASC cases and revealed CIN2+ lesions in 22 (14.4%). Follow‐up histology was available in 50 (44.2%) of LSIL cases and revealed clinically significant abnormalities in five (10%), all of which were CIN2. CIN3 and invasive squamous carcinomas were seen in 5.9% and 1.4%, respectively, of cases of ASC, and not seen in LSIL. Reclassification of ASC smears into ASC‐US (ASC‐undetermined significance) and ASC‐H (ASC‐ high grade SIL not excluded) revealed ASC‐H in 2.6% of all ASC smears, with a clinically significant outcome in 45.4%. Conclusion: In a low‐resource setting where human papillomavirus testing is unaffordable, the threshold for colposcopic referral and follow‐up histology should be ASC rather than SIL.     

Columnar and metaplastic cells in vault smears: cytologic and colposcopic study

Vault smears (n= 250) were examined as routine follow up of hysterectomized individuals. Although the majority of these smears were normal, 14 of them revealed the presence of columnar cells or metaplastic cells. None of these patients had any known cause which could account for the presence of these cells in a post-hysterectomy smear. The possible explanations could be (i) the common mullerian origin of the upper vaginal mucosal cells, (ii) exfoliated reparative squamous parabasal and basal cells mimicking columnar cells, (iii) goblet cell metaplasia in atrophic vaginal epithelium.     

Use of a liquid-based, thin-layer Pap test in a community hospital. Impact on cytology performance and productivity

OBJECTIVE: To evaluate the direct-to-vial efficacy of the SurePath Pap test (TriPath Imaging, Burlington, North Carolina, U.S.A.) in a community hospital laboratory and to assess its impact on productivity, as measured by Pap test turnaround times (TATs). STUDY DESIGN: A total of 8,771 SurePath Pap tests were compared to 5,055 conventional Pap smears collected and processed over the same 12-month period. SurePath histologic correlation rates were compared to historical correlation rates for conventional Pap smears. Pap test TATs for 3 months prior to implementing SurePath were compared to TATs for the last 3 months of the study, which included an approximate 70:30 ratio of SurePath to conventional Pap tests. Laboratory staffing was unchanged, and mean monthly accessions were relatively constant. RESULTS: SurePath showed statistically significant improvements in the detection of low grade (LSIL) (196%) and high grade (HSIL) (243%) squamous intraepithelial lesions (SILs) relative to conventional Pap smears. The atypical cells of undetermined significance (ASCUS) rate remained nearly constant with SurePath, while the ASCUS/SIL ratio decreased by 68%. Unsatisfactory rates declined 81%. Histologic correlation rates with SurePath increased over those of conventional Pap smears. Pap test mean TATs improved 73% with SurePath. CONCLUSION: Sure-Path detected significantly more cases of LSIL and HSIL than conventional smears without compromising specificity. The ASCUS/SIL ratio and unsatisfactory rate declined dramatically. Pap test TATs also improved markedly with SurePath.     

Fibromatosislike metaplastic carcinoma of the breast as a diagnostic pitfall for fine needle aspiration cytology: a case report

BACKGROUND Metaplastic carcinomas of the breast are uncommon, and most display marked cellular atypia. Recently, a low grade fibromatosis-like metaplastic carcinoma was found and displayed little nuclear atypia. CASE A 74-year-old woman presented with a 2.5-cm, palpable breast nodule. Mammogram was reported as suspicious for malignancy. Cytologic examination revealed smears of low cellularity with most cells lying in clusters and having a round or oval shape. Rare cells had a "spindle" shape. Nuclear features were low grade. Rare individual cells had retained cytoplasm. Lumpectomy revealed a fibromatosis-like metaplastic carcinoma. CONCLUSION: Cytologically, fibromatosis-like metaplastic carcinomas are low grade lesions producing smears of relatively low cellularity. Separation from ductal carcinomas is necessary because fibromatosis-like metaplastic carcinomas rarely metastasize to lymph nodes.