Metaplastic carcinomas of the breast--fine needle aspiration (FNA) cytology findings

Combined Use of Mammography and FNA Eliminates Pitfalls in the Management of Metaplastic Breast Carcinoma

BACKGROUND

Due to its heterogeneity, metaplastic breast carcinoma (MBC) poses diagnostic dilemmas, leading to delayed treatment, thereby aggravating the prognosis. Over the years, there has been controversy regarding the role of fine-needle aspiration (FNA) cytology in timely diagnosis.

CASE REPORT

A 54-year-old woman presented with a palpable mass in the upper outer quadrant of her right breast with corresponding mammographic findings and FNA was performed. The smears revealed small- and medium-sized cohesive clusters of malignant cells with atypical nuclei. Sporadically, there was a pleomorphic population of notably large mononuclear cells, with disturbance of nuclear/cytoplasmic ratio, and binucleated or multinucleated malignant cells. The presence of chondromyxoid substance with focally embedded cells in a magenta-colored substrate was predominant in the background. These features, along with the corresponding mammographic findings, allowed for high preoperative suspicion of MBC. Surgical resection followed immediately without neoadjuvant chemotherapy; the pathology report led to the definite diagnosis of MBC.

DISCUSSION

MBC is a rare clinical entity with unfavorable prognosis, thus early diagnosis is imperative regarding its management. The effectiveness of FNA in the diagnostic algorithm has been questioned, with data from literature being rather contradictory. FNA seems to provide valuable information, which should always be interpreted in correlation with the clinical and mammographic findings.

CONCLUSION

High preoperative suspicion of MBC with the combination of mammography and FNA cytology necessitated the surgical excision of the lesion as the principal treatment approach. Although the role of FNA in the diagnosis of MBC is debatable, its combination with clinical presentation and corresponding mammographic findings may prevent the administration of neoadjuvant chemotherapy in patients with ambiguous indications, given the poor response rate of this cancer subtype.

Indeterminate and erroneous fine-needle aspirates of breast with focus on the 'true gray zone': a review

OBJECTIVE

To review our experience and the literature on inconclusive/erroneous fine-needle aspirates (FNAs) of breast with the focus on the 'true gray zone'. To describe the cytology, differential diagnosis, pitfalls and limitations of common and rare lesions.

STUDY DESIGN

We conducted a literature search focusing on breast FNAs with statistical data of C3 and C4 categories including false-positive and false-negative cases. Similar data from 2003 to 2009 was obtained from our institution.

RESULTS

C3 and C4 categories account for 3-17% of breast FNAs. Contributing factors are technical difficulties, inexperienced pathologists interpreting FNAs of breast and overlap of cytologic features of certain benign and malignant conditions; this last, 'true gray zone' accounts for 2% of cases. Fibroadenoma, proliferative breast lesions, gynecomastia, infiltrating and in situ low-grade adenocarcinomas and tubular, cribriform, lobular and mucinous carcinomas are the most common problematic lesions. Granular cell tumor, adenomyoepithelioma, pregnancy-related lesions, fat necrosis, inflammatory and radiation changes, adenoid cystic carcinoma, spindle-cell lesions and Phyllodes tumor are less common.

CONCLUSION

Inconclusive/erroneous FNAs of breast due to the 'true gray zone' are rare. Most are due to the overlapping cytologic features of some benign and malignant conditions. Practical features that may help arrive at the correct diagnoses are elucidated.

Infiltrating myoepithelial carcinoma of the breast, a case report and cytologic-histologic correlation

Introduction

Infiltrating myoepithelial carcinoma remains a rarely encountered lesion of the breast. The few cases that have surfaced firmly document the histopathology of this tumor, but its cytologic characteristics seemingly have been described in only one other report.

Case presentation

Here we present the cytologic findings from a case of infiltrating myoepithelial carcinoma of the breast in a 52-year-old female and provide a histologic correlation with the subsequent biopsy and mastectomy specimens. While the cytology specimens displayed more myoepithelial cellular heterogeneity than was present on histology, a number of cytologic features including hypercellularity, pleomorphic spindle cells, and mitotic activity correlated well with the histopathology.

Conclusion

The role of fine needle aspiration in the diagnosis of mammary myoepithelial carcinoma, in this case, was to establish malignancy rather than to arrive at a specific diagnosis, as a number of different entities potentially can mimic this neoplasm on cytologic specimens.

Metaplastic breast carcinoma with chondrosarcomatous differentiation: fine-needle aspiration cytology findings. A case report

Metaplastic carcinoma (carcinoma with pseudosarcomatous metaplasia) of the breast are high-grade carcinomas in which much of the tumor undergoes metaplastic change producing a pseudosarcomatous pattern. We report a case of metaplastic breast carcinoma (MBC) in whom fine-needle aspiration (FNA) cytology was performed with later histological confirmation. The lesion affected a 68-yr-old woman, with a tumor measuring 6.4 x 5.3 cm well demarcated mass located in the upper outer quadrant of the right breast. FNA cytology revealed a variety of markedly atypical cells, mainly spindle-shaped, and mitotic figures sporadically distributed against a severely necrotic background. Atypical chondrocytes were observed against a background of myxomatous substance that displayed metachromasia with May-Giemsa stain that resembled chondrosarcoma cells. Clusters of markedly atypical carcinoma cells that exhibited epithelial junctions were also seen, and immunostaining confirmed the presence of both mesenchyme-marker-positive sarcomatous and epithelial-marker-positive carcinoma cells. Careful attention to the precise cellular composition such as sarcomatous cells, chondrosarcomatous cells and carcinoma cells should allow the recognition of these neoplasms. Therefore, MBC seems to be very a characteristic tumor in which accurate cellular diagnosis may be achieved by FNA cytology.

Metaplastic carcinoma of the breast, an unusual disease with worse prognosis: the experience of the European Institute of Oncology and review of the literature

BACKGROUND

Metaplastic carcinoma of the breast is a rare form of breast cancer and has an uncertain prognostic significance. The purpose of the present study was to compare the clinical course, and prognosis, between this type of tumor and poorly differentiated ductal carcinoma.

PATIENTS AND METHODS

We analyzed 37 cases of metaplastic carcinoma of the breast treated at our institution (European Institute of Oncology in Milan, Italy) between 1997 and 2004, comparing them with 72 cases (control group) of poorly differentiated ductal carcinoma. All 109 patients had negative receptors and were G3 at final histology. The control cases were matched according to year of surgery, pT (pT1 vs. pT2/3/4), and pN (absent vs. present).

RESULTS

Of the 37 patients, eleven died from disease progression, eight developed metastatic disease and two experienced local recurrence. In the control group (72 patients) we observed three deaths due to disease progression, 13 distant metastases, and two local recurrences.

CONCLUSION

The overall survival in the metaplastic carcinoma group was significantly worse than in the control group. As regards to disease-free survival, there was no statistically significant difference between the two groups.

Metaplastic breast cancer: clinical significance

BACKGROUND

Metaplastic breast carcinoma (MBC) is a rare poorly differentiated breast cancer characterized by coexistence of ductal carcinoma with areas of matrix producing, spindle-cell, sarcomatous, or squamous differentiation; ER/PR/HER2 negativity; and a reputation for poor outcome.

METHODS

The Swedish Cancer Institute prospective breast cancer database (> 6500 patients; 1990-2005) has 24 MBC cases that were compared with typical breast cancer cases matched for age, date of diagnosis, stage, and ER/PR/HER2 status.

RESULTS

The mean metaplastic primary tumor diameter was 2.5 cm. The histological/nuclear grade was high in 21 of 24 cases. No patient had distant metastasis. ER and/or PR receptor status was negative in all cases. HER2 was negative in 10 of 11 cases tested. EGFR (HER1) was positive in 7 of 7 cases tested. All patients had sentinel and/or axillary lymph node dissection and surgical resection; 18 received chemotherapy and 22 had radiation therapy. Four patients had distant recurrences 5 to 88 months from diagnosis. Five-year survival was 83% (95% confidence interval, 66-100%). Comparison with matched typical breast cancer cases revealed no major significant difference in multidisciplinary treatment patterns, recurrence, or survival.

CONCLUSION

MBC is associated with poor prognostic indicators, but outcomes comparable with matched typical breast cancer cases can be achieved with routine aggressive multidisciplinary care. Increased, expression of EGFR (HER1) provides an opportunity for targeted tumor therapy.

Cytomorphology of Rare Malignant Tumors of the Breast

This article reviews cytomorphology of rare malignant tumors of the breast: squamous carcinoma, metaplastic carcinoma, adenoid cystic carcinoma, apocrine carcinoma, secretory carcinoma, lipid-rich carcinoma, and carcinoma with choriocarcinomatous features. It is important to bear in mind the cytomorphology and diagnosis of rare malignant tumors of the breast in analysis of breast fine needle aspiration smears. Although rare, these malignant tumors can be diagnosed by the cytomorphological characteristics, and should be included in the differential diagnoses of breast neoplasms.

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.

Metaplastic breast carcinoma on fine-needle cytology samples: A report of three cases

Metaplastic breast carcinoma (MBC) may have a varied presentation on fine-needle cytology samples. We herewith describe three cases of MBC found in our series. One of these cases showed a peculiar mixture of malignant ductal, apocrine type, and squamous epithelial cells with fascicles of spindle cells with variable degree of atypia and was diagnosed as metaplastic carcinoma of the carcino-sarcomatous type. The other two lesions were characterized by an abundant chondroid extracellular matrix to which were variably admixed carcinomatous and chondroid-type cells, with variable degree of atypia. Both these latter cases were defined as matrix-producing metaplastic carcinomas. Because of the various presentation of MBC on fine-needle cytology samples and the possible influence of needle "sampling" on the cytological specimen, the spectrum of differential diagnoses to be considered may encompass a number of benign and malignant entities, like keratinous subareolar cysts, malignant fibroepithelial lesions with myxo-chondroid stroma, and true sarcomas of the breast, with cartilaginous metaplasia. It is the Authors' feeling that, with optimal samples, the cytomorphological findings of this rare variant of breast carcinoma permit its accurate pre-operative diagnosis.

Aspiration cytology of sarcomatoid carcinoma of the breast: Report of a case with cystic change

Sarcomatoid/metaplastic carcinomas of the breast are rare breast malignancies that show a myriad of cytohistologic patterns in aspirates. These poorly differentiated invasive carcinomas contain both ductal and mesenchymal elements with transitional forms displaying either spindle, squamous, chondroid, or osseous differentiation. We describe such a neoplasm in a 68-yr-old woman, the diagnosis of which was missed at the initial fine-needle aspiration (FNA) due to cystic change. Extensive cystic change in a sarcomatoid carcinoma is unusual and is reported for the first time in the English literature.

Cytological features of epithelioid mesenchymal neoplasms: A study of 21 cases

Epithelioid mesenchymal neoplasms (EMNs) are rare tumors that share cytological, histological, and immunohistochemical features with epithelial tumors. It is important to distinguish EMNs from epithelial tumors in cytology specimens due to their different clinical management and prognosis. The cytomorphological features of histologically confirmed EMN were reviewed. Twenty-one cytological specimens of EMN were evaluated and characterized by polygonal cells with moderate to abundant dense cytoplasm, prominent nucleoli, and pleomorphism. Additional findings included the presence of a distinct population of spindle cells, hemosiderin-containing cells, multinucleated cells, and granuloma-like structures in selected cases. Cytokeratin immunoreactivity was seen in two cases and was negative in one case. This study shows that the cytological features of EMNs and epithelial tumors overlap; nonetheless, some features are more helpful in suggesting EMN. A panel of immunocytochemical studies must include specific mesenchymal markers to avoid a misdiagnosis of carcinoma in cases of cytokeratin-positive EMN.

Diagnosis of recurrent uterine carcinosarcoma by fine-needle aspiration cytology: report of a case

Uterine carcinosarcomas are uncommon, aggressive neoplasms usually afflicting postmenopausal women. Histologically, they are characterized by the presence of both malignant epithelial and stromal cells. The latter may be either homologous or heterologous in nature. The cytologic diagnosis of carcinosarcoma via fine-needle aspiration (FNA) was previously described for primary tumors arising in the parotid gland, breast, lung, and ovary. Although the diagnosis of uterine carcinosarcoma via cervicovaginal, endometrial, and peritoneal fluid cytology has been described, the FNA cytology diagnosis of recurrent uterine carcinosarcoma has only been rarely described. We present a case of recurrent uterine carcinosarcoma in a 59-yr-old woman, diagnosed by ultrasound-guided FNA cytology. Cytologic smears showed a biphasic neoplasm consisting of both malignant columnar epithelial and spindle cells, in a background of tumor diathesis. This case illustrates the diagnostic utility of aspiration cytology in the investigation of recurrent carcinosarcoma in clinically suspicious lesions arising postsurgery.