Fine-needle aspiration cytology of breast carcinoma with endocrine differentiation

Cytological study of 44 cases with solid papillary carcinoma and a systemic review of solid papillary carcinoma and neuroendocrine tumor of the breast

BACKGROUND

Solid-papillary carcinoma (SPC) of the breast is a rare variant of low-grade in situ and invasive carcinoma but there are only a few of the cytologic studies.

METHODS

We examined 44 cases of SPC of the breast to define the cytologic features. We also made a systemic review of reported cases of SPC and neuroendocrine tumor (NET) of the breast.

RESULTS

Both of our and the reviewed cases with SPC were very similar in the cytologic finding. It included hypercellularity, highly discohesive clusters, numerous isolated cells, small nuclei, finely granular chromatin of salt-and-pepper appearance, inconspicuous nucleoli, low nuclear-cytoplasmic ratio, and a plasmacytoid appearance. Moreover, SPC and NET had frequently all of these features in common. Capillary vessels structures and mucinous substance were not frequently seen in our and the reviewed cases with SPC. Rosette and pseudorosette were very rare in the cytologic specimen. The immunocytochemistry with our 9 cases with SPC indicated diffuse positivity for chromogranin A and/or synaptophysin.

CONCLUSION

Many cytologic features are frequently shared by SPC and NET of the breast. However, the vascular structure may not be a precise criterion for SPC. Rosette and pseudorosette are rarely helpful for the cytologic diagnosis.

The Effect of the Extent of Neuroendocrine Differentiation on Cytopathological Findings in Primary Neuroendocrine Neoplasms of the Breast

Objective:

This study aimed to describe the cytological features of neuroendocrine breast tumors and to show the effect of the extent of neuroendocrine differentiation on cytological features.

Methods:

Breast tumor excision materials showing immunostaining with neuroendocrine markers (Synaptophysin or Chromogranin A) were determined and divided into two groups: cases with focal (10%–50% of tumor cells) staining and cases with diffuse (>50% of tumor cells) staining. A group of cases without neuroendocrine features/staining was used as control group. Fine needle aspiration biopsy specimens of the tumor mass or metastatic lymph nodes were examined and compared.

Results:

Twenty cases with neuroendocrine differentiation were included. Eleven cases were in the diffuse group, nine cases were in the focal group. Clean background, high cellularity, loosely cohesive cell groups with monotonous appearance, and naked nuclei were more common in the diffuse group. On the contrary, tight cohesive cell groups, the proportion of large cells, nuclear pleomorphism, and nucleolar prominence were higher in the group with focal staining. Plasmocytoid appearance, isolated cell groups, and binucleation were in similar distribution in both groups. Although round-oval nuclei were dominant in both groups, round nuclei were observed to be slightly more in the diffuse group. Only two cases in diffuse group showed cytoplasmic granularity and one case in focal group showed necrosis and mitosis. In the control group, tight cohesive groups, large cell size, pleomorphism, prominent nucleoli, and coarse chromatin were more commonly encountered.

Conclusions:

Clean background, hypercellularity, loss of cohesion, naked nuclei, monotonous cells with round nucleus, and granular cytoplasm were more prominent in cases showing diffuse staining with neuroendocrine markers. Suspecting neuroendocrine differentiation in tumors that show focal staining with neuroendocrine markers can be challenging in cytological preparations.

Papillary lesions of the breast: A systematic evaluation of cytologic parameters

BACKGROUND

The cytologic diagnosis of papillary lesions of the breast is challenging because of the diverse morphology, including epithelial hyperplasia, atypia, low-grade malignancy, and neuroendocrine differentiation; also, traditional malignant features such as necrosis and myoepithelial cell loss can be lacking. Thus, the diagnostic criteria for papillary lesions may differ from those for other breast lesions. This study evaluated various cytologic parameters in a large cohort to identify useful diagnostic features.

METHODS

Cytologic preparations of papillary lesions with histologic follow-up were reviewed for features related to cellularity, epithelial cohesiveness, cellular and stromal architecture, cytomorphology, and background. Corresponding histologic slides were also reviewed.

RESULTS

In all, 153 cases were included. Epithelial discohesion, solid and cribriform patterns, atypical nuclear features, and mitoses (P ≤ .001 to P = .017) were associated with malignancy. Cell balls, monolayer sheets, and features of cystic change (P < .001 to P = .016) were associated with benign lesions. Complex (P = .031) and slender (P = .026) papillae and neuroendocrine features (P < .001) were associated with malignancy. Hemorrhage, background, and infiltrating neutrophils (P < .001 to P = .025) were associated with malignancy; fibrotic broad papillary stromal fragments (naked papillary fronds [NPFs]; P = .043) were associated with benignity. The presence of any single parameter, including the absence of myoepithelial cells within epithelial structure, the presence of cytoplasmic granules, an increased amount of cytoplasm, and a nuclear to cytoplasmic (N/C) ratio greater than 0.7, which were identified by principal component analysis, yielded a sensitivity of 95.1% and a specificity of 100.0% in predicting malignancy.

CONCLUSIONS

Methodological assessment of multiple features is recommended. Myoepithelial cells, cytoplasmic granules, the amount of cytoplasm, and the N/C ratio are key features for diagnosis.

Mucinous carcinoma of the breast: a comparative study on cytohistological findings associated with neuroendocrine differentiation

OBJECTIVE

Mucinous carcinoma (MCA) may show neuroendocrine differentiation (ND), but the cytological features characteristic of ND remains elusive. We compared fine needle aspiration (FNA) findings of MCA between cases with high and low degrees of ND.

METHODS

Histological sections of 37 MCA cases were immunohistochemically evaluated for expression of chromogranin A and synaptophysin, and were graded as 0 to 3+ degrees of ND. They were divided into low ND (grade 0 and 1+) and high ND (grade 2+ and 3+) groups. Pre-operative FNA samples of each group were assessed for cytological features.

RESULTS

The mean age of the high ND group (n = 18) was higher than the low ND group (n = 19, P = 0.01). In FNA samples of the high ND group, 17 cases showed moderate to severe degrees of discohesiveness, but low ND cases mainly showed no or only mild discohesiveness (P < 0.001). Nine of the low ND cases displayed overlapped, cohesive cell clusters, whereas, in the high ND cases, the cells were arranged in a loose, flat and monolayered pattern (P = 0.045). Fourteen of the high ND cases had round nuclei, but oval nuclei were predominant in the low ND cases (P = 0.027). The nuclei were eccentrically located in 12 of the high ND cases but were centrally located in 14 of the low ND cases (P = 0.01).

CONCLUSIONS

Mucinous carcinoma with high ND may be diagnosed by the presence of discohesiveness, a flat, monolayered pattern, and round or eccentrically located nuclei. Features of ND in carcinomas in other organs, such as intracytoplasmic granules and coarse chromatin, may not be reliable cytological features of ND in MCA.

Fine needle aspiration cytology of invasive micropapillary carcinoma of the breast

AIM

To determine the pathognomonic diagnostic cytological features of invasive micropapillary carcinoma of the breast which is a poor prognostic subtype of infiltrating ductal carcinoma.

METHODS

A series of 20 histologically proven tumours were reviewed retrospectively to evaluate the various cytological features, including tumour morules, isolated malignant cells, staghorn epithelial structures, mucinous background and apocrine metaplasia.

RESULTS

Tumour morules formation and isolated malignant cells were the two most reliable and constant cytological features, being present in 75% (15/20 cases) of cases. Staghorn epithelial structures were present in 35% (7 cases). Mucinous background (2 cases, 10%) and apocrine metaplasia (4 cases, 20%) of the tumour cells were seen in a few cases only and did not appear very helpful.

CONCLUSION

Tumour morules formation, isolated malignant cells and staghorn epithelial structures are the most reliable cytological features, and the presence of these should raise suspicion of invasive micropapillary carcinoma.

Cytological study of 20 cases of solid-papillary carcinoma of the breast

Solid-papillary carcinoma (SPC) of the breast is a rare variant of low-grade intraductal carcinoma but there are few cytological studies. We examined 20 cases of SPC of the breast, aged 31-80 (mean age 66.0 yr), to define the cytological features. In each of the cytological specimens, we could find both malignant and benign cytological features; the former were characterized by hypercellularity, highly discohesive clusters, numerous isolated cells, and severe overcrowding cells, while the latter were marked by small and bland nuclei, a low nuclear-cytoplasmic ratio, and inconspicuous nucleoli. Neither abnormal naked nuclei of tumor cell origin nor oval naked nuclei of myoepithelial cell origin were seen. We also reviewed the cytological findings of SPC as well as neuroendocrine carcinomas with intraductal components that had been reported and we concluded that the coexistence of malignant and benign features was the most characteristic cytological feature of SPC.

Role of fine needle aspiration and tru cut biopsy in diagnosis of mucinous carcinoma of breast—from a radiologist's perspective

This study was to assess whether fine needle aspiration (FNA) or core biopsy would allow diagnosis of mucinous carcinoma of breast. In 37 mucinous carcinoma in 34 patients, 20 lesions had FNA and 24 lesions with core biopsy. FNA achieved a sensitivity of 66.7% in diagnosis of malignant lesions and 56% sensitivity in diagnosis of mucinous carcinoma. Core biopsy achieved 100% sensitivity and accuracy in the diagnosis of malignant lesions and mucinous carcinoma.

Bcl-x(L)-mediated changes in metabolic pathways of breast cancer cells: from survival in the blood stream to organ-specific metastasis

Bcl-x(L) protein plays a role in breast cancer dormancy, promoting survival of cells in metastatic foci by counteracting the proapoptotic signals in the microenvironment. The aim of this study was to identify phenotypes mediated by Bcl-x(L) in breast cancer cells that enhance in vivo survival of clinical metastases. 435/Bcl-x(L) or 435/Neo human breast cancer cells were injected into the inguinal mammary gland of nude mice, and tumors, metastases in lymph node, lung, and bone, and bloodstream surviving cells were examined. Proteomic analysis identified 17 proteins that were overexpressed (more than twofold) or underexpressed (less than twofold) in metastases. A protein interaction program allowed us to functionally associate peroxiredoxin 3, peroxiredoxin 2, carbonyl reductase 3, and enolase 1, suggesting a role for cellular responses to oxidative stress in metastasis organ selection. The prediction included proteins involved in redox systems, kinase pathways, and the ATP synthase complex. Furthermore, the interaction of redox proteins with enolase 1 suggests a connection between glycolysis and antioxidant pathways, enabling achievement of a high metastatic activity. In conclusion, Bcl-x(L) mediates a phenotype in which redox pathways and glycolysis are coupled to protect breast cancer metastatic cells during transit from the primary tumor to the metastatic state.

Metastatic mammary carcinomas with endocrine features: Potential diagnostic pitfalls

Mammary carcinomas with endocrine differentiation (MCED) are an uncommon subtype of breast carcinomas that are morphologically indistinguishable from low-grade endocrine neoplasms arising in other organs. Aspirates of MCED yield relatively monotonous cells with eccentrically placed nuclei containing characteristic "salt and pepper" chromatin. In the breast, these features represent MCED. In extramammary sites, the differential is more extensive, and diagnosing MCED metastases to the lung, a common location for primary and metastatic endocrine tumors, can be a challenging task, with significant clinical implications. Although primary MCED have been described extensively in the cytology literature, secondary pulmonary MCED have not been reported to the best of our knowledge. We report three cases of MCED metastatic to the lung and present the cytological and immunohistochemical features.

Fine-needle aspiration cytology findings of an uncommon micropapillary variant of pure mucinous carcinoma of the breast: review of patients over an 8-year period

BACKGROUND

Previous attempts at subclassifying pure mucinous carcinomas of the breast based on architectural patterns and other associated features are on record. A distinctive micropapillary variant with most tumor cells arranged in micropapillae/pseudoacini has not been described previously.

METHODS

The author reviewed the histologic slides from all 556 patients who underwent wide excision/mastectomy for mammary ductal carcinoma, either in situ or invasive, at Pamela Youde Nethersole Eastern Hospital, Hong Kong, during an 8-year period from early 1994 to the end of 2001. Five patients with pure mucinous carcinoma with diffuse micropapillary architecture were noted. The cytologic features (if available) were correlated with clinical, radiologic, and pathologic findings.

RESULTS

Among the five patients with pure mammary mucinous carcinoma (micropapillary variant), three patients underwent preoperative fine-needle aspiration biopsies and had specimens available for review. The direct smears and cytospin preparations were of moderate cellularity and showed cohesive clusters and micropapillae of mildly pleomorphic tumor cells among a mucoid background. True tumor papillae with fibrovascular cores were not present. Nuclear hobnailing was observed commonly, and occasional psammoma bodies were found. There were also scanty isolated tumor cells scattered around. The pseudoacinar pattern was appreciated more readily in the cell block sections. Histologic examination of the surgical specimens showed features of pure mucinous carcinoma with diffuse micropapillary architecture. The micropapillary arrangement was confirmed further by the demonstration of a reverse polarity immunostaining pattern for epithelial membrane antigen and the identification of microvilli rimming the periphery of tumor cell clusters under the electron microscope. Peritumoral lymphovascular permeation and ipsilateral axillary lymph node metastasis was found in one of the patients.

CONCLUSIONS

The micropapillary variant of mammary mucinous carcinoma demonstrates characteristic cytologic and histologic features that warrant special attention. It may represent the mucinous counterpart of invasive micropapillary carcinoma. Further analysis of a larger series of patients, however, will be required to delineate its prognostic significance, especially its propensity for lymph node metastasis.