Open AccessTriple-negative pleomorphic lobular carcinoma and expression of androgen receptor: Personal case series and review of the literature
Author(s) -
Kohei Taniguchi,
Shinichi Takada,
Masako Omori,
Takuro Igawa,
M. Nishimura,
Toshiaki Morito,
Kouichi Ichimura,
Tadashi Yoshino
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0235790
Subject(s) - apocrine , androgen receptor , triple negative breast cancer , immunohistochemistry , pathology , invasive lobular carcinoma , lobular carcinoma , carcinoma , breast carcinoma , biology , medicine , breast cancer , cancer , invasive ductal carcinoma , prostate cancer , ductal carcinoma
Pleomorphic lobular carcinoma (PLC) is a histological variant of invasive lobular carcinoma (ILC) and is associated with worse prognosis than classical ILC. It exhibits a greater degree of cellular atypia and pleomorphism and is occasionally accompanied with apocrine morphology. We investigated the immunohistochemical characteristics of samples from 31 Japanese patients with PLC to elucidate the clinicopathological characteristics of PLC including androgen receptor (AR) immunoreactivity. The surrogate molecular subtypes were luminal A-like, luminal B-like, luminal B-like/HER2, HER2-type, and triple-negative in 5, 4, 3, 5, and 14 cases, respectively. AR was positive in 92.8% (13/14) of the triple-negative PLC cases and 100% (10/10) of the non-triple-negative PLC cases. Disease-specific survival was worse in patients with histological grade 3 PLCs than in those with histological grade 2 PLCs ( p = 0.007). However, there was no significant difference in the progression-free survival between the two groups ( p = 0.152). No other clinicopathological characteristics were associated with prognosis. These results reveal that PLC exhibits various surrogate molecular subtypes and that the triple-negative subtype frequently expresses AR. The observed molecular apocrine differentiation implicates that triple-negative PLC can be categorized into the luminal AR subtype. Furthermore, AR-targeted therapy might be useful for patients with triple-negative PLC.