Clinicopathologic characteristics of HER2-positive pure mucinous carcinoma of the breast

Abstract

Breast mucinous carcinoma (MC) is defined as floating tumor clusters within extracellular mucin pools [1]. MC is divided into two subtypes, pure and mixed, according to the proportion of mucinous component in the tumor [1]. Pure MC (PMC) is composed of more than 90% mucinous component, is a rare type of breast cancer accounting for approximately 2% of invasive cancers, and usually occurs in elderly patients (> 55 years) [1,2]. PMC generally has a low nuclear grade and good prognosis [1,3]. Typical PMC is positive for estrogen receptor (ER) and progesterone receptor (PR), whereas it is negative for human epidermal growth factor receptor 2 (HER2) [1,3,4]. While HER2 overexpression occurs in 15%-20% of invasive breast cancers [5], it has been reported in only 2.6-9.0% of PMC [4,6-8]. Clinicopathologic characteristics of HER2-positive PMC have not been studied well because of the rarity of this entity. Herein, we investigate the clinicopathologic characteristics of HER2positive PMC.

Invasive Stratified Mucin-producing Carcinoma (ISMC) of the Uterine Cervix: Clinicopathological and Molecular Characteristics With Special Emphasis on the First Description of Consistent Programmed Death-ligand 1 (PD-L1) Over-expression

“…Immunohistochemical staining. Immunostaining was performed using an automated immunostainer (Ventana BenchMark XT, Ventana Medical Systems, Tucson, AZ, USA) (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). After antigen retrieval, 4-μm-thick, formalin-fixed, paraffin-embedded slices were incubated with primary antibodies, including p16 (prediluted, clone E6H4, Ventana Medical Systems), p40 (1:100, polyclonal, Biocare Medical, Concord, CA, USA), carcinoembryonic antigen (CEA; 1:200, clone II-7, Dako, Glostrup, Denmark), erb-b2 (prediluted, clone 4B5, Ventana Medical Systems), and PD-L1 (prediluted, clone 22C3, Agilent Technologies, Santa Clara, CA, USA).…”

Ovarian Mesonephric-like Adenocarcinoma With Multifocal Microscopic Involvement of the Fimbrial Surface: Potential for Misdiagnosis of Tubal Intraepithelial Metastasis as Serous Tubal Intraepithelial Carcinoma Associated With Ovarian High-grade Serous Carcinoma

“…Immunostaining was performed to confirm our diagnosis, as previously described (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28). A panel of antibodies against Wilms tumor 1 (WT1), p53, estrogen receptor (ER), paired box 8 (PAX8), PAX2, GATA-binding protein 3 (GATA3), and P16 was used.…”

Mesonephric-like Differentiation of Endometrial Endometrioid Carcinoma: Clinicopathological and Molecular Characteristics Distinct from Those of Uterine Mesonephric-like Adenocarcinoma

“…Four-micrometer-thick, formalin-fixed, paraffin-embedded sections were deparaffinized and rehydrated using xylene and alcohol solutions. Immunostaining was performed using automated instruments [7,16,[21][22][23][24][25][26][27]. After antigen retrieval, the sections were incubated with primary antibodies against paired box 8 (PAX8, 1:50, polyclonal, Cell Marque, Rocklin, CA, USA), PAX2 (1:100, polyclonal, Invitrogen, Thermo Fisher Scientific, Waltham, MA, USA), GATA-binding protein 3 (GATA3, 1:400, clone L50-823, Cell Marque), Wilms tumor 1 (WT1, 1:800, clone 6F-H2, Cell Marque), estrogen receptor (ER, 1:150, clone 6F11, Novocastra, Leica Biosystems, Newcastle Upon Tyne, UK), progesterone receptor (PR, 1:100, clone 16, Novocastra), p16 (prediluted, clone E6H4, Ventana Medical Systems), p53 (1:300, clone DO-7, Novocastra), and phosphatase and tensin homolog deleted on chromosome 10 (PTEN, prediluted, clone SP218, Ventana Medical Systems).…”

“…DNA and RNA were quantified using a Qubit 2.0 Fluorometer (Thermo Fisher Scientific). DNA libraries were prepared as previously described [7,[23][24][25]29,30,32,33]. These DNA libraries were generated from 20 ng of DNA per sample using an Ion Am-pliSeq Library Kit 2.0 (Thermo Fisher Scientific) and an Oncomine Comprehensive Assay (OCA) v1 panel (Thermo Fisher Scientific).…”