Aldehyde dehydrogenase 1A1 (ALDH1A1) is a cancer stem cell (CSC) marker related to clinical outcomes in breast cancer (BC). The aim of this study was to analyze the relationship between ALDH1A1, programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) in triple negative (TN) and human epidermal growth factor receptor 2-positive (HER2+) BC tumors, and its association with clinicopathological characteristics and outcomes. A retrospective, historical cohort study of patients diagnosed with early or locally advanced BC treated with neoadjuvant chemotherapy was conducted. ALDH1A1, PD-L1 expression and TILs were assessed using immunohistochemistry. A total of 75 patients were analyzed (42.7% TN, 57.3% HER2+ tumors). ALDH1A1+ was related to HTILs (p = 0.005) and PD-L1+ tumors (p = 0.004). ALDH1A1+ tumors presented higher CD3+ (p = 0.008), CD4+ (p = 0.005), CD8+ (p = 0.003) and CD20+ (p = 0.006) TILs. ALDH1A1+ (p = 0.018), PD-L1+ (p = 0.004) and HTILs (p < 0.001) were related to smaller tumors. ALDH1A1+ was related to pathologic complete response (pCR) (p = 0.048). At the end of the follow-up (54.4 [38.3–87.6] months), 47 patients (62.7%) remained disease-free, and 20 (26.7%) had died. HTILs were related to improved disease-free survival (p = 0.027). ALDH1A1+ was related to PD-L1+ and HITLs, that might be related to higher pCR rates with neoadjuvant therapy.

Background: Luminal advanced breast cancer (ABC) patients eventually progress on endocrine therapy. REVERT aimed to explore whether eribulin could restore endocrine sensitivity in a randomized, non-comparative phase II trial. Methods: Aromatase inhibitor (AI)-resistant patients with luminal ABC were randomized 1:1 to receive eribulin +/− AI. Patients were stratified by prior cyclin-dependent kinases 4/6 inhibitor (CDK4/6i) treatment. The primary endpoint was an investigator-assessed overall response rate (ORR) according to RECIST version 1.1 in the eribulin + AI arm. An interim analysis was planned with 11 evaluable patients according to a two-stage Simon design. Results: Twenty-two patients were enrolled (15 eribulin + AI arm; 7 eribulin arm). The trial was terminated early in March 2021, with eight (36.4%) patients still on treatment. ORR was 26.7% in the eribulin + AI arm (95% CI, 7.8–55.1%; p = 0.0541). In the eribulin arm, two (28.6%) patients had an objective response (95% CI, 3.7–71.0%). The difference between the study arms was not significant (p = 0.918). The addition of AI to eribulin also failed to show improvement in other efficacy endpoints. A significant interaction between the treatment arm and previous CDK4/6i treatment was observed for ORR (p = 0.018) and progression-free survival (p = 0.084). Overall, the toxicity profile was consistent with the known safety profile of eribulin. No treatment-related deaths were reported. Conclusion: Eribulin + AI does not seem to improve outcomes compared with eribulin monotherapy in patients with AI-resistant luminal ABC. This chemo–endocrine approach deserves further investigation after progression to CDK4/6i-based therapy.

Metastatic breast cancer (mBC) has become a chronic disease for a growing number of women thanks to therapeutic advances, generating a new population of patients with prolonged response. This article, written by experts in oncology and primary care (PC) in Spain, offers practical recommendations for the comprehensive management of these patients. It addresses strategies to improve therapeutic compliance, the detection and management of toxicities, the early identification of signs of progression, and the management of comorbidities and drug interactions. In addition, it emphasizes the importance of psychosocial support, the promotion of healthy habits, and coordination between oncology and PC to optimize quality of life and continuity of care. The effective integration of PC in the follow-up of patients with mBC and prolonged response is key to maintaining therapeutic benefits and the overall well-being of patients.

Humanization in cancer care is increasingly recognized as a core component of healthcare quality, yet its implementation in clinical practice remains uneven. To address this gap, the Spanish Society of Medical Oncology (SEOM) developed a humanization protocol to guide its integration into routine oncology care. Based on a review of scientific literature, including clinical guidelines and documents from scientific societies, together with a SEOM survey of medical oncologists, the recommendations are organized around four domains: people, processes, spaces, and society. For each domain, practical and adaptable measures are proposed, ranging from communication and shared decision-making to care coordination, the design of healthcare environments, professional well-being, and community engagement. A cross-cutting person-centered approach, combined with regular evaluation using patient-experience and professional well-being indicators, may support the integration of humanization into routine cancer care.