In female breast cancer (BC), elastosis is strongly related to estrogen receptor alpha (ERα) expression. Male breast cancers almost invariably express ERα; so, the aim of this study was to investigate elastosis frequency in invasive male BC as well as clinicopathological correlations, in comparison with females. A total of 177 male BC cases and 135 female BC cases were included, all ERα-positive and invasive carcinoma of no special type. Elastosis on H&E-stained slides was scored in a four-tiered system as elastosis grade (EG) 0 (no elastosis) to EG3 (high amount of elastosis). EG scores in male BC were correlated to histopathological characteristics and overall surviva and compared with female BC EG scores. Male BC showed some degree of elastosis in 26/117 cases (22.2%) with none showing EG3, while female BC cases showed elastosis in 89/135 cases (65.9%) with 21.5% showing EG3 (p < 0.001). This difference retained its significance in multivariate logistic regression. In male BC cases, no significant correlations were found between the amount of elastosis and age, grade, mitotic activity index, and PgR. In addition, no significant prognostic value of elastosis was seen. In conclusion, despite high ERα expression, male BC showed significantly less elastosis than female BC. Elastosis did not show clinicopathological correlations or prognostic value. Therefore, elastosis seems to be a less useful ERα tissue biomarker with less clinical significance in male BC compared with females, pointing towards important BC sex differences.

在女性乳腺癌 (BC) 中，弹性组织增生与雌激素受体α (ERα) 的表达密切相关。男性乳腺癌几乎总是表达 ERα；因此，本研究的目的是研究与女性相比，侵入性男性 BC 的弹性组织增生频率以及临床病理学相关性。共纳入177例男性BC病例和135例女性BC病例，均为ERα阳性且无特殊类型的浸润癌。H&E 染色载玻片上的弹性组织在四层系统中评分为弹性组织分级 (EG) 0（无弹性组织）至 EG3（大量的弹性组织）。男性 BC 的 EG 评分与组织病理学特征和整体存活率相关，并与女性 BC 的 EG 评分进行比较。男性 BC 在 26/117 例 (22.2%) 中显示出一定程度的弹性组织变性，没有显示出 EG3，p < 0.001)。这种差异在多元逻辑回归中保持其显着性。在男性 BC 病例中，弹性组织的数量与年龄、等级、有丝分裂活动指数和 PgR 之间没有发现显着相关性。此外，没有观察到弹性组织的显着预后价值。总之，尽管 ERα 表达高，但雄性 BC 的弹性组织显着低于雌性 BC。弹性组织变性未显示临床病理学相关性或预后价值。因此，与女性相比，在男性 BC 中，弹性组织似乎是一种不太有用的 ERα 组织生物标志物，其临床意义较小，表明 BC 存在重要的性别差异。