title: Axillary metaplastic breast carcinoma with ipsilateral pectoral invasive ductal carcinoma: an unusual presentation.
abstract: We report a case of axillary metaplastic breast carcinoma (MBC) with triple negative (ER-/PR-/Her2-) phenotype, concurrent with multifocal invasive ductal carcinoma (IDC) of ipsilateral pectoral breast (ER+/PR+/Her2-) in a 60-year-old woman. The two tumors demonstrate different morphology, immunophenotype, and opposite response to neoadjuvant chemotherapy of paclitaxol, adriamycin, and cyclophosphamide. Methylation analysis of human androgen receptor (HUMARA) on X-chromosome identified monoclonal pattern of X-chromosome inactivation in MBC and mosaic pattern in the IDC. Stem cell origin of MBC is suggested in this case. Clinicopathological features, imaging findings, biological markers, chemoradiation management, and prognosis of MBC are reviewed in comparison to invasive ductal carcinoma. Our case and literature review suggest that traditional chemotherapy applicable to IDC is less effective towards MBC. However, new chemotherapy protocols targeting stem cell and multimodality management of MBC are promising. Recognition of unusual presentation of MBC will help tailor therapy towards tumor with worse prognosis.
authors.affiliation: Department of Pathology, University of Hawaii, 651 Ilalo Street, No. 411E, Honolulu, HI 96813, USA ; Mercy Hospitals at Bakersfield, 2215 Truxtun Avenue, Bakersfield, CA 93301, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Cancer Center of Hawaii, 2226 Liliha Street, Honolulu, HI 96817, USA.
authors.forename: Sabahattin
authors.initials: S
authors.lastname: Comertpay
authors.affiliation: Department of Pathology, University of Hawaii, 651 Ilalo Street, No. 411E, Honolulu, HI 96813, USA.
authors.forename: David
authors.initials: D
authors.lastname: Shimizu
authors.affiliation: Department of Pathology, University of Chicago, 5841 South Maryland Avenue MARP 212, MC 2050, Chicago, IL 60637, USA.
authors.forename: Richard M
authors.initials: RM
authors.lastname: DeMay
authors.affiliation: Department of Pathology, University of Hawaii, 651 Ilalo Street, No. 411E, Honolulu, HI 96813, USA ; Cancer Center of Hawaii, 2226 Liliha Street, Honolulu, HI 96817, USA.
authors.forename: Michele
authors.initials: M
authors.lastname: Carbone
authors.affiliation: Department of Pathology, University of Hawaii, 651 Ilalo Street, No. 411E, Honolulu, HI 96813, USA.
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Honda
authors.affiliation: Department of Pathology, University of Hawaii, 651 Ilalo Street, No. 411E, Honolulu, HI 96813, USA.
authors.forename: Jodi M Matsuura
authors.initials: JM
authors.lastname: Eaves