Single progesterone receptor-positive phenotype has the similar clinicopathological features and outcome as triple-negative subtype in metastatic breast cancer

Yunbo Luo; Hongyu Pu; Fangwei Li; Shuangqiang Qian; Jingtai Chen; Xiaobo Zhao; Lingmi Hou

doi:10.3389/fonc.2023.1029648

Single progesterone receptor-positive phenotype has the similar clinicopathological features and outcome as triple-negative subtype in metastatic breast cancer

Front Oncol. 2023 Feb 24:13:1029648. doi: 10.3389/fonc.2023.1029648. eCollection 2023.

Authors

Yunbo Luo¹, Hongyu Pu¹, Fangwei Li¹, Shuangqiang Qian¹, Jingtai Chen², Xiaobo Zhao^{1

3}, Lingmi Hou^{1

4}

Affiliations

¹ Department of Thyroid and Breast Surgery, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.
² Department of Thyroid and Breast Surgery, Chongqing People's Hospital, Chongqing, China.
³ Laboratory of Thyroid (Parathyroid) and Breast Disease, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.
⁴ Department of Academician (expert) Workstation, Biological Targeting Laboratory of Breast Cancer, Breast and Thyroid Surgery, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.

Abstract

Objective: The same clinicopathological features and prognosis have been reported between single progesterone receptor-positive (sPR-positive) and triple-negative phenotype in early-stage breast cancer, but such similarity has not been studied in metastatic breast cancer (MBC). Therefore, the purpose of this study was to estimate the difference between sPR-positive phenotype and other phenotypes in MBC.

Methods: Patients with HER-2-negative MBC were selected from the Surveillance, Epidemiology and End Results database. Pearson's χ2 test was used to compare the difference of clinicopathologic factors between sPR-positive phenotype and other phenotypes. Univariate and multivariate analyses were performed to evaluate the effects of hormone receptor (HoR) phenotypes and other clinicopathologic factors on the cancer-specific survival (CSS) and overall survival (OS).

Results: Overall, 10877 patients including 7060 patients (64.9%) with double HoR-positive (dHoR-positive), 1533 patients (14.1%) with single estrogen receptor-positive (sER-positive), 126 patients (1.2%) with sPR-positive and 2158 patients (19.8%) with double HoR-negative (dHoR-negative) were analyzed. The patients with sPR-positive or dHoR-negative were more likely to be younger, higher grade and tumor stage, visceral and brain metastasis than ER-positive phenotypes (P<0.001). MBC with sPR-positive had the similar CSS (HR: 1.135, 95%CI: 0.909-1.417, P=2.623) and OS (HR: 1.141, 95%CI: 0.921-1.413, P=0.229) as dHoR-negative, but worse outcome than ER-positive phenotypes. Chemotherapy significantly improved the survival for MBC, especially for sPR-positive MBC (CSS, HR: 0.39, 95%CI: 0.213-0.714, P=0.002; OS, HR: 0.366, 95%CI: 0.203-0.662, P=0.001).

Conclusions: Patients with sPR-positive and triple-negative have similar biological behavior and prognosis in MBC. Chemotherapy may be a preferred recommendation for MBC with sPR-positive.

Keywords: chemotherapy; endocrine therapy; metastatic breast cancer; outcome; single progesterone receptor-positive.

Grants and funding

This research was supported by grant from North Sichuan Medical College Scientific Research and Development Project (CBY22-QNA34).