title: Invasive lobular breast cancer and its variants: how special are they for systemic therapy decisions?
abstract: The WHO classification of breast tumors distinguishes, besides invasive breast cancer 'of no special type' (former invasive ductal carcinoma, representing 60-70% of all breast cancers), 30 special types, of which invasive lobular carcinoma (ILC) is the most common (5-15%). We review the literature on (i) the specificity and heterogeneity of ILC biology as documented by various analytical techniques, including the results of molecular testing for risk of recurrence; (ii) the impact of lobular histology on prediction of prognosis and effect of systemic therapies in patients. Though it is generally admitted that ILC has a better prognosis than IDC, is endocrine responsive, and responds poorly to chemotherapy, currently available data do not unanimously support these assumptions. This review demonstrates some lack of specific data and a need for improving clinical research design to allow oncologists to make informed systemic therapy decisions in patients with ILC. Importantly, future studies should compare various endpoints in ILC breast cancer patients among the group of hormonosensitive breast cancer.
authors.affiliation: Department of Medical Oncology, Georges-François Leclerc Cancer Center, 1 rue du Professeur Marion, 21000 Dijon, France; Department of Medical Oncology, CHUV, rue du Bugnon 46, 1011 Lausanne, Switzerland. Electronic address: sguiu@cgfl.fr.
authors.forename: Séverine
authors.initials: S
authors.lastname: Guiu
authors.affiliation: Department of Medical Oncology, CHUV, rue du Bugnon 46, 1011 Lausanne, Switzerland.
authors.forename: Anita
authors.initials: A
authors.lastname: Wolfer
authors.affiliation: Department of Medical Oncology, Institute of Cancerology of Montpellier, 208 Avenue des Apothicaires-Parc Euromédecine, 34298 Montpellier Cedex 5, France.
authors.forename: William
authors.initials: W
authors.lastname: Jacot
authors.affiliation: Department of Medical Oncology, Georges-François Leclerc Cancer Center, 1 rue du Professeur Marion, 21000 Dijon, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Fumoleau
authors.affiliation: Department of Medical Oncology, Institute of Cancerology of Montpellier, 208 Avenue des Apothicaires-Parc Euromédecine, 34298 Montpellier Cedex 5, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Romieu
authors.affiliation: Oncology Unit of Methodology and Quality of Life (EA 3181), CHU Besançon, 2 place Saint-Jacques, 25000 Besançon, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Bonnetain
authors.affiliation: University Institute of Pathology, CHUV, rue du Bugnon 25, 1011 Lausanne, Switzerland.
authors.forename: Maryse
authors.initials: M
authors.lastname: Fiche
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D018275:Carcinoma, Lobular / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D005260:Female; D005820:Genetic Testing; D023281:Genomics; D006801:Humans; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D011379:Prognosis; D016896:Treatment Outcome
keywords: Invasive breast cancer; Invasive lobular carcinoma; Luminal breast cancer; Pleomorphic invasive lobular carcinoma; Predictive factor; Prognosis; Tubulo-lobular carcinoma