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Review
. 2015 Apr 1;11(2):59-66.
doi: 10.5152/tjbh.2015.1669. eCollection 2015 Apr.

Molecular Classification of Breast Carcinoma: From Traditional, Old-Fashioned Way to A New Age, and A New Way

Nuket Eliyatkın  1 , Evrim Yalçın  2 , Baha Zengel  3 , Safiye Aktaş  4 , Enver Vardar  1
Affiliations
Review

Molecular Classification of Breast Carcinoma: From Traditional, Old-Fashioned Way to A New Age, and A New Way

Nuket Eliyatkın et al. J Breast Health. .

Abstract

Breast carcinoma comprises a group of diseases with specific clinical, histopathologic and molecular properties. Traditional classification use morphology to divide tumors into separate categories with differing behavior and prognosis. However, there are limitations of traditional classification systems, and new molecular methods are expected to improve classification systems. Molecular subtypes of breast carcinomas have been characterized in the last 11 years, and have been studied extensively. Much of the information accumulated in recent years, and molecular taxonomy seems to be still developing and undergoing change. The main question is whether new molecular techniques such as gene expression profiling will be accepted as gold standard in determining breast cancer subtypes, and whether molecular classification is useful in specific subtypes of breast cancer as it is in ductal carcinoma (nonspecific type). In addition, critical review of the literature reveals major problems such as poor definition, lack of reproducibility and lack of quality control in current molecular techniques and classifications. Therefore, current molecular approaches are not yet used in routine clinical practice and treatment guidance since they are immature and can even lead to incorrect assessment.

Keywords: Breast cancer; immunohistochemistry; microarray gene expression; the molecular classification.

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Conflict of interest statement

Conflict of Interest: No conflict of interest was declared by the authors.

Figures

Figure 1. a–d
Figure 1. a–d
Intratumoral heterogenity with H&E, IHC and CISH. (a) Comedo-type ductal carcinoma insitu morphology containing focal invasive ductal carcinoma (b) Heterogenity in breast carcinoma lymph node metastasis (papillary, micropapillary and ductal morphology) (c) ER positivity and heterogeneity in breast carcinoma (d) Intratumoral heterogeneity with CISH
Figure 2. a–d
Figure 2. a–d
Specific subtype examples (a) Invasive cribriform carcinoma (b) Mucinous carcinoma (c) Medullary carcinoma (d) Invasive lobular carcinoma, containing lobular carcinoma insitu foci
See this image and copyright information in PMC

References

    1. Jemal A, Bray F, Center MM, Ferlay J, Ward E, Forman D. Global cancer statistics. CA Cancer J Clin. 2011;61:69–90. http://dx.doi.org/10.3322/caac.20107. - DOI - PubMed
    1. Singletary SE, Connolly JL. Breast cancer staging: working with the sixth edition of the AJCC Cancer Staging Manual. CA Cancer J Clin. 2006;56:37–47. - PubMed
    1. Ellis IO, Cornelisse CJ, Schnitt SJ, Sasco AJ, Sastre-Garau X, Kaaks R. Invasive breast carcinomas. In: Tavassoli FA, Devilee P, editors. WHO Classification of Tumours Pathology and Genetics of Tumours of the Breast and Female Genital Organs. Lyon: IARC Press; 2003. pp. 13–19.
    1. Weigelt B, Reis-Filho JS. Histological and molecular types of breast cancer: is there a unifying taxonomy? Nat Rev Clin Oncol. 2009;6:718–730. http://dx.doi.org/10.1038/nrclinonc.2009.166. - DOI - PubMed
    1. Buerger H, Otterbach F, Simon R, Schäfer KL, Poremba C, Diallo R, Brinkschmidt C, Dockhorn-Dworniczak B, Boecker W. Different genetic pathways in the evolution of invasive breast cancer are associated with distinct morphological subtypes. J Pathol. 1999;189:521–526. - PubMed