Scholarlink

Background <p>Emerging evidence indicates that estrogen receptor-low (ER-low)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer (BC) may more closely resemble ER-negative (ER-zero, &lt; 1%) rather than ER-positive disease in terms of biological and clinicopathological characteristics. In Sweden, ER-low (ER 1–9%) BC is managed as triple-negative breast cancer (TNBC) and is thus eligible for neoadjuvant chemo-immunotherapy. We aimed to investigate real-world pathological response to neoadjuvant pembrolizumab combined with chemotherapy in ER-low versus ER-zero BC patients within a Swedish population-based multi-center cohort.</p> Methods <p>BC patients with indication to receive neoadjuvant pembrolizumab in combination with chemotherapy in Sweden between 2022 and 2024 were included in the study. Clinicopathological data—including pathological complete response (pCR) status, residual cancer burden (RCB) score, stromal tumor-infiltrating lymphocytes (sTILs) levels, and routine tumor characteristics—were retrieved from laboratory information systems. Associations between categorical variables were assessed using chi-squared (χ<sup>2</sup>) tests and associations between continuous variables and ER status or pCR were analyzed using Mann–Whitney U-test.</p> Results <p>The total cohort comprised 441 TNBC cases (ER-zero n = 398; ER-low n = 43). In the ER-zero group, the pCR rate and RCB score 0–1 were 50.5% (95% CI: 45.5% to 55.5%) and 60.8% (95% CI: 55.8% to 65.6%), respectively. In the ER-low group, the corresponding values were 58.1% (95% CI: 42.1% to 73%), and 60.5% (95% CI: 44.4% to 75%), respectively. There were no statistically significant differences in either pCR rate (<i>p</i> = 0.46) or dichotomized RCB score (<i>p</i> = 0.88) between the groups. The ER-low group showed significantly higher sTILs percentage compared to the ER-zero group (median sTILs 25% versus 20%, <i>p</i> = 0.046). However, when sTILs were analyzed as a binary categorical variable using a 30% cut-off, no significant difference was observed (<i>p</i> = 0.33).</p> Conclusions <p>We observed no significant difference in pathological response to neoadjuvant chemo-immunotherapy with pembrolizumab between ER-zero and ER-low BCs. These findings support previous evidence suggesting that ER-low tumors behave more similarly to ER-zero than ER-positive.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Pathological response to pembrolizumab-based neoadjuvant therapy in ER-low vs. ER-zero breast cancer: a Swedish population-based cohort study

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年11月29日

查看全文
  • Sanna Steen,
  • Emelie Karlsson,
  • Ida Björnheden,
  • Gunilla Rask,
  • Viktoria Thurfjell,
  • Hampus Nobin,
  • Blanka Kolodziej,
  • Anna Bodén,
  • Annette Bauer,
  • Rickard Einefors,
  • Per Nilsson,
  • Ioannis Zerdes,
  • Andri Papakonstantinou,
  • Theodoros Foukakis,
  • Irma Fredriksson,
  • Mattias Rantalainen,
  • Eugenia Colón-Cervantes,
  • Anikó Kovács,
  • Balazs Acs,
  • Johan Hartman

摘要

Background

Emerging evidence indicates that estrogen receptor-low (ER-low)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer (BC) may more closely resemble ER-negative (ER-zero, < 1%) rather than ER-positive disease in terms of biological and clinicopathological characteristics. In Sweden, ER-low (ER 1–9%) BC is managed as triple-negative breast cancer (TNBC) and is thus eligible for neoadjuvant chemo-immunotherapy. We aimed to investigate real-world pathological response to neoadjuvant pembrolizumab combined with chemotherapy in ER-low versus ER-zero BC patients within a Swedish population-based multi-center cohort.

Methods

BC patients with indication to receive neoadjuvant pembrolizumab in combination with chemotherapy in Sweden between 2022 and 2024 were included in the study. Clinicopathological data—including pathological complete response (pCR) status, residual cancer burden (RCB) score, stromal tumor-infiltrating lymphocytes (sTILs) levels, and routine tumor characteristics—were retrieved from laboratory information systems. Associations between categorical variables were assessed using chi-squared (χ2) tests and associations between continuous variables and ER status or pCR were analyzed using Mann–Whitney U-test.

Results

The total cohort comprised 441 TNBC cases (ER-zero n = 398; ER-low n = 43). In the ER-zero group, the pCR rate and RCB score 0–1 were 50.5% (95% CI: 45.5% to 55.5%) and 60.8% (95% CI: 55.8% to 65.6%), respectively. In the ER-low group, the corresponding values were 58.1% (95% CI: 42.1% to 73%), and 60.5% (95% CI: 44.4% to 75%), respectively. There were no statistically significant differences in either pCR rate (p = 0.46) or dichotomized RCB score (p = 0.88) between the groups. The ER-low group showed significantly higher sTILs percentage compared to the ER-zero group (median sTILs 25% versus 20%, p = 0.046). However, when sTILs were analyzed as a binary categorical variable using a 30% cut-off, no significant difference was observed (p = 0.33).

Conclusions

We observed no significant difference in pathological response to neoadjuvant chemo-immunotherapy with pembrolizumab between ER-zero and ER-low BCs. These findings support previous evidence suggesting that ER-low tumors behave more similarly to ER-zero than ER-positive.