Surrogate molecular subtyping of breast carcinomas– A study on recent modifications and their clinicopathological significance
Context: Breast carcinoma is a heterogenous disease with varied clinicopathological features and response to therapy. Molecular classification through gene studies helps in planning therapy but has economic constraints. Hence immunohistochemical subtyping of breast carcinomas has been used as a surrogate method. Criteria for this subtyping has undergone many modifications since it was originally proposed.
Objectives: To immunohistochemically subtype breast carcinomas based on St.Gallen 2017 guidelines and analyse the differences in clinicopathological parameters like age, tumour size, histopathological grade and lymph node staging between the various subtypes.
Materials and methods: The study was done retrospectively at a tertiary care health centre in South India on breast carcinoma patients from January 2017 to June 2020. Immunohistochemistry was done with antibodies to the Estrogen receptor, Progesterone receptor, Human epidermal growth factor receptor-2 (HER-2) and Ki-67. Immunohistochemical Subtypes were correlated with Clinicopathological features.
Results: The study had 107 cases. Hormone receptor (HR) positive HER-2 negative was the most common subtype (55 cases, 51.4%). This subtype frequently presented without nodal metastasis (58.2%) and in >50 years of age (56.4%). Triple-negative subtype frequently presented with grade III (69.2%), highest nodal metastasis stage (38.5%) and in < 50 years of age (69.2%). Difference in grade, tumour size and nodal metastasis stage between the different subtypes was significant with p <0.001.
Conclusion: St.Gallen 2017 guidelines for immunohistochemical subtyping classified breast carcinomas into groups that differed significantly in their clinicopathological features. Further studies on differences in treatment response and survival rate differences between these different subtypes are needed.
Curigliano G, Burstein HJ, P Winer E, Gnant M, Dubsky P, Loibl S, Colleoni M, Regan MM, Piccart-Gebhart M, Senn HJ, Thürlimann B. De-escalating and escalating treatments for early-stage breast cancer: the St. Gallen International Expert Consensus Conference on the Primary Therapy of Early Breast Cancer 2017. Annals of Oncology. 2017 Aug 1;28(8):1700-12.
Eliyatkın N, Yalçın E, Zengel B, Aktaş S, Vardar E. Molecular classification of breast carcinoma: from traditional, old-fashioned way to a new age, and a new way. The journal of breast health. 2015 Apr;11(2):59.
Spitale A, Mazzola P, Soldini D, Mazzucchelli L, Bordoni A. Breast cancer classification according to immunohistochemical markers: clinicopathologic features and short-term survival analysis in a population-based study from the South of Switzerland. Annals of oncology. 2009 Apr 1;20(4):628-35.
Gnant M, Harbeck N, Thomssen C. St. Gallen 2011: summary of the consensus discussion. Breast care. 2011;6(2):136-41.
Vasconcelos I, Hussainzada A, Berger S, Fietze E, Linke J, Siedentopf F, Schoenegg W. The St. Gallen surrogate classification for breast cancer subtypes successfully predicts tumor presenting features, nodal involvement, recurrence patterns and disease free survival. The Breast. 2016 Oct 1;29:181-5.
Zaha DC, Lazar E, Lazureanu C. Clinicopathologic features and five years survival analysis in molecular subtypes of breast cancer. Rom J Morphol Embryol. 2010 Jan 1;51(1):85-
Yang XR, Sherman ME, Rimm DL, Lissowska J, Brinton LA, Peplonska B, Hewitt SM, Anderson WF, Szeszenia-Dąbrowska N, Bardin-Mikolajczak A, Zatonski W. Differences in risk factors for breast cancer molecular subtypes in a population-based study. Cancer Epidemiology and Prevention Biomarkers. 2007 Mar 1;16(3):439-43.
Su Y, Zheng Y, Zheng W, Gu K, Chen Z, Li G, Cai Q, Lu W, Shu XO. Distinct distribution and prognostic significance of molecular subtypes of breast cancer in Chinese women: a population-based cohort study. BMC cancer. 2011 Dec 1;11(1):292.
Batra A, Marwah N, Marwah S, Gupta S, Dharembra D, Sen R. St. Gallen's molecular subtypes in primary breast carcinoma in Indian population. Clinical Cancer Investigation Journal. 2016 Sep 1;5(5):416.
Munjal K, Ambaye A, Evans MF, Mitchell J, Nandedkar S, Cooper K. Immunohistochemical analysis of ER, PR, Her2 and CK5/6 in infiltrative breast carcinomas in Indian patients. Asian Pac J Cancer Prev. 2009 Jan 1;10(5):773-8.
Karangadan S, Patil AG, Andola SK. Immunohistochemical characterization of molecular classification of breast carcinoma and its relation with Ki-67. Clinical Cancer Investigation Journal. 2016 Sep 1;5(5):430.
Kunheri B, Raj RV, Vijaykumar DK, Pavithran K. Impact of St. Gallen surrogate classification for intrinsic breast cancer sub-types on disease features, recurrence, and survival in South Indian patients. Indian Journal of Cancer. 2020 Jan 1;57(1):49.
Onitilo AA, Engel JM, Greenlee RT, Mukesh BN. Breast cancer subtypes based on ER/PR and Her2 expression: comparison of clinicopathologic features and survival. Clinical medicine & research. 2009 Jun 1;7(1-2):4-13.
Engstrøm MJ, Opdahl S, Hagen AI, Romundstad PR, Akslen LA, Haugen OA, Vatten LJ, Bofin AM. Molecular subtypes, histopathological grade and survival in a historic cohort of breast cancer patients. Breast cancer research and treatment. 2013 Aug 1;140(3):463-73.
Piñero-Madrona A, Polo-García L, Alonso-Romero JL, Salinas-Ramos J, Canteras-Jordana M, Sola-Pérez J, Galindo-Fernández PJ, Illana-Moreno J, Bermejo-López J, Navarrete-Montoya A, Parrilla-Paricio P. Immunohistochemical characterisation of breast cancer: towards a new clasification?. Cirugia espanola. 2008 Sep 1;84(3):138-45.
Blows FM, Driver KE, Schmidt MK, Broeks A, Van Leeuwen FE, Wesseling J, Cheang MC, Gelmon K, Nielsen TO, Blomqvist C, Heikkilä P. Subtyping of breast cancer by immunohistochemistry to investigate a relationship between subtype and short and long term survival: a collaborative analysis of data for 10,159 cases from 12 studies. PLoS med. 2010 May 25;7(5):e1000279.
Tang P, Skinner KA, Hicks DG. Molecular classification of breast carcinomas by immunohistochemical analysis: are we ready?. Diagnostic Molecular Pathology. 2009 Sep 1;18(3):125-32.
Carey LA, Perou CM, Livasy CA, Dressler LG, Cowan D, Conway K, Karaca G, Troester MA, Tse CK, Edmiston S, Deming SL. Race, breast cancer subtypes, and survival in the Carolina Breast Cancer Study. Jama. 2006 Jun 7;295(21):2492-502.
Cheang MC, Chia SK, Voduc D, Gao D, Leung S, Snider J, Watson M, Davies S, Bernard PS, Parker JS, Perou CM. Ki67 index, HER2 status, and prognosis of patients with luminal B breast cancer. JNCI: Journal of the National Cancer Institute. 2009 May 20;101(10):736-50.
Cheang MC, Voduc D, Bajdik C, Leung S, McKinney S, Chia SK, Perou CM, Nielsen TO. Basal-like breast cancer defined by five biomarkers has superior prognostic value than triple-negative phenotype. Clinical cancer research. 2008 Mar 1;14(5):1368-76.
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