Prognostic Analysis of Hormone Receptors and HER2 in Breast Squamous Cell Carcinoma: A Matched Study Using the SEER Database

• Published in: Clinical breast cancer Vol. 25; no. 6; pp. e739 - e749.e2
• Main Authors: Wang, Miao, Hu, Kehua, Gao, Yanping, Guo, Xiaowan, Li, Jie, Xia, Yaoxiong, Qiu, Hui, Wu, Qiuji
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2025
• Subjects: Adult; Aged; Breast cancer; Breast Neoplasms - metabolism; Breast Neoplasms - mortality; Breast Neoplasms - pathology; Carcinoma, Ductal, Breast - metabolism; Carcinoma, Ductal, Breast - mortality; Carcinoma, Ductal, Breast - pathology; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - mortality; Carcinoma, Squamous Cell - pathology; Female; Humans; Incidence; Kaplan-Meier Estimate; Middle Aged; Prognosis; Propensity Score; Propensity score matching; Rare tumor; Receptor subtype; Receptor, ErbB-2 - metabolism; Receptors, Estrogen - metabolism; Receptors, Progesterone - metabolism; SEER Program - statistics & numerical data; Survival Rate; Triple Negative Breast Neoplasms - epidemiology; Triple Negative Breast Neoplasms - mortality; Triple Negative Breast Neoplasms - pathology; Propensity score matching; Breast cancer; Prognosis; Rare tumor; Receptor subtype
• DOI: 10.1016/j.clbc.2025.04.015
• ISSN: 1526-8209; 1938-0666

To determine the prognostic differences between breast squamous cell carcinoma (BSCC) and breast infiltrating ductal adenocarcinoma (BIDC) by receptor subtype. We extracted data from the SEER Registry for adult women diagnosed with BSCC and BIDC from 2010 to 2020. Kaplan-Meier curves and log-rank tests assessed survival differences. Propensity score matching analysis (PSM) was used to match subjects with similar characteristics. Cox proportional hazard regression models identified survival predictors. BSCC patients were older (> 60 years: 60.6% vs. 52.4%, P = .037), had higher TNBC incidence (64.0% vs. 12.2%, P = .001), and higher metastasis rates (48% vs. 33.3%, P < .001) compared to BIDC. Marriage rate was lower in BSCC patients (44.6% vs. 54.9%, P = .009). BSCC patients had worse OS and CSS (P < .001). In non-TNBC, BSCC showed poor survival before and after PSM (P < .05). In TNBC, BSCC had worse OS than BIDC (P < .001), but similar CSS before PSM. After PSM, no survival difference was observed. Stage was a significant prognostic factor for BSCC (P < .001), while receptor subtype was not (P > .05). BSCC has a higher TNBC incidence and poorer survival in non-TNBC populations compared to BIDC. BSCC-TNBC patients have similar survival to BIDC-TNBC. Stage is a crucial prognostic factor for BSCC, more so than receptor subtype. This study compared prognostic differences between breast squamous cell carcinoma (BSCC) and breast infiltrating ductal adenocarcinoma (BIDC) based on receptor subtypes using SEER registry data. Receptor subtype-based stratified survival analyses demonstrated that BSCC had a poorer survival in non-TNBC populations compared to BIDC, while BSCC-TNBC patients had similar survival to BIDC-TNBC. Notably, stage is a crucial prognostic factor for BSCC, more so than receptor subtype. These findings highlight that BSCC represents a highly aggressive malignancy, suggesting increased clinical attention in treatment strategies.