Search

Introduction: Medullary breast carcinomas (MBCs) are distinguished by circumscribed, high-grade morphology with dense chronic inflammation; they are associated with the basal phenotype but have a relatively good prognosis.Methods: This study aimed to review the clinicopathological features of MBCs diagnosed at the Department of Pathology, Singapore General Hospital and correlate them with immunohistochemical expression of hormonal markers and c-erbB-2, the basal markers p53, cytokeratin (CK) 14, epidermal growth factor receptor (EGFR) and 34BE12, and the follow-up outcome.Results: Using Ridolfi's criteria for histologic reviews, 62 patients previously diagnosed as having 'typical MBC' (n = 26), 'atypical MBC' (n = 32) and 'invasive carcinoma with focal medullary-like features' (n = 4) were re-classified as follows: 'typical MBC' (n = 6; 9.7%), 'atypical MBC' (n = 46; 74.2%), and 'non-medullary infiltrating carcinoma' (n = 10; 16.1%). Clinicopathological parameters, including ethnicity, age, tumour size and concurrent ductal carcinoma in situ (DCIS), showed no statistically significant correlation with review diagnoses and immunohistochemical findings. Presence of lymphovascular invasion and nodal stage were significantly correlated with recurrence and breast cancer-related deaths, respectively. ER negativity was significantly correlated with triple positivity for basal markers CK14, EGFR and 34BE12, which comprised patients who showed a significantly decreased disease-free survival rate within a 10-15-year follow-up period.Conclusions: Lymphovascular invasion and high nodal stage as well as triple negativity among typical and atypical MBCs that have basal-like phenotype represent a portion of invasive carcinomas with medullary features that may have poor outcomes in this otherwise relatively good prognostic group. [ABSTRACT FROM AUTHOR]

Aim To document and clarify the nature of intranuclear inclusions of luminal epithelium in benign proliferative breast lesions. Methods and results Five benign breast lesions were selected which showed intranuclear inclusions within epithelial cells on light microscopy. Following confirmation of their luminal epithelial (non-myoepithelial) localisation by immunohistochemistry, ultrastructural examination was performed with the following observations: (1) presence of deep nuclear indentations occasionally verging on nuclear inclusions; (2) inclusions with features of helioid bodies; and (3) a morphological spectrum of helioid bodies and their focal coexistence. Conclusion Intranuclear inclusions of breast epithelium are likely of cytoplasmic origin. Helioid bodies may be formed by a stepwise process, the nature of which needs further study. [ABSTRACT FROM AUTHOR]

Jara-Lazaro A R, Akhilesh M, Thike A A, Lui P C-W, Tse G M-K & Tan P H (2010) Histopathology 57, 220–232 Predictors of phyllodes tumours on core biopsy specimens of fibroepithelial neoplasms Aims: To establish histological and biological parameters that can predict phyllodes tumours on core biopsy specimens of indeterminate fibroepithelial neoplasms. Methods and results: Core biopsy specimens of fibroepithelial lesions diagnosed at the Department of Pathology, Singapore General Hospital from 2002 to 2007 were reviewed. Cases in which phyllodes tumour was favoured, or could not be ruled out, were evaluated for stromal cellularity/distribution, nuclear atypia and mitoses, stromal overgrowth, epithelial fronding, epithelial hyperplasia, configuration of lesional edge, presence of pseudoangiomatous stromal hyperplasia and of adipose tissue. Antibodies to Ki67, topoisomerase IIα, CD34, CD117 and Bcl-2 were applied to sections subjected to immunohistochemistry using the streptavidin–biotin method. Findings were correlated with subsequent excisions. Of 261 core biopsy specimens of fibroepithelial lesions, 98 (37%) comprised cases in which phyllodes tumour could not be excluded and 57 (58%) had subsequent open surgical excisions. Marked stromal hypercellularity (5/5; 100%) and nuclear atypia (1/1; 100%), stromal overgrowth (17/17; 100%), mitoses ≥2/10 high-power fields (18/18; 100%) and ill-defined lesional borders (16/16 phyllodes tumours; 100%) were features in core biopsy specimens that exclusively predicted phyllodes tumour on excision. Moderate stromal hypercellularity (20/27 phyllodes tumours; 74%), stromal overgrowth, moderate nuclear atypia (14/16 phyllodes tumours; 87%), pseudoangiomatous stromal hyperplasia (19/23 phyllodes tumours; 83%) significantly correlated with their subsequent excisions. Immunohistochemical markers Ki67 ≥5% and topoisomerase IIα≥5%, and reduced or patchy CD34 on core biopsy specimens correlated significantly with a diagnosis of phyllodes. Conclusions: Stromal hypercellularity, combined with key histological features and immunohistochemical markers Ki67, topoisomerase IIα and CD34, reinforced by clinical findings, can predict phyllodes tumours on core biopsy specimens. [ABSTRACT FROM AUTHOR]

Tse G M, Tan P-H, Lacambra M D, Jara-Lazaro A R, Chan S-K, Lui P C, Ma T K F, Vong J S, Ng D C H, Shi H-J & Lam W W (2010) Histopathology 56, 481–488 Papillary lesions of the breast—accuracy of core biopsy Aims: To assess the accuracy of diagnosing papillary breast lesions in core needle biopsy. Methods and results: One hundred biopsy specimens of papillary breast lesions were reviewed and compared with the final excisional diagnoses. The discordant biopsy specimens were stained for oestrogen receptor (ER), cytokeratin (CK) 14 and p63, and these specimens were reclassified based on these results. The overall core biopsy accuracy, false-positive and false-negative rate were 79%, 5% and 16%, respectively. A benign core biopsy specimen diagnosis gave a false-negative rate of 10%, and malignant core biopsy specimen diagnosis did not give any false-positive results. Using homogeneous ER (epithelial), positive CK14 (epithelial) and p63 (myoepithelial) immunoreactivity as benign criteria, the discordant rate was reduced by 30% and 69% when using all three or two of these three criteria for diagnosis. However, false-positive and -negative cases could not be totally eliminated. Conclusions: Immunohistochemistry is helpful in core biopsy diagnosis of papillary breast lesions, but some cases remained misdiagnosed. [ABSTRACT FROM AUTHOR]