🌸 Breast Cancer — 2026-W35

What this page is. Every paper the week's monitor reviewed — including the ones that did not go into the digest. Material marked “Not selected” was reviewed and deliberately left out. It has not been fact-checked to digest standard and is not endorsed. For the curated read, see the digest itself.

Biomarker analysis from the phase 3 RxPONDER trial in HR-positive/HER2-negative, node-positive breast cancer, published in Annals of Oncology. Shows that baseline AMH (ovarian reserve) helps identify which premenopausal women derive chemotherapy benefit, refining patient selection beyond recurrence score alone.

Prognostic/exploratory biomarker analysis from the phase 2 c-TRAK TN study comparing tissue-free versus tumor-informed ctDNA assays for molecular residual disease in early triple-negative breast cancer, published in JAMA Oncology. Suggests tissue-free ctDNA testing may simplify MRD surveillance workflows, though it doesn't yet demonstrate a specific treatment-selection benefit tied to a drug decision.

Systematic review and meta-analysis of studies in early-stage ER-low, HER2-negative breast cancer, published in JNCI. Finds endocrine therapy is associated with improved disease-free and overall survival in ER-low tumors, supporting continued use of endocrine therapy in this ambiguous subgroup.

Development and validation study (JNCI) of a clinical prediction model for aromatase inhibitor-induced joint pain in early breast cancer patients on adjuvant therapy. Could help identify patients at risk for arthralgia to guide monitoring/adherence support, though model discrimination was modest and it does not predict treatment response.

Secondary analysis from a large single-arm phase 2 trial (EA1181/CompassHER2) in stage II/IIIa HER2-positive breast cancer, published in JCO. Reports pathologic complete response rates and clinicopathologic predictors of response to neoadjuvant taxane/trastuzumab/pertuzumab, informing which patients might benefit from de-escalated regimens pending survival data.

Pooled individual-patient-data analysis of three pre-CDK4/6i-era randomized trials in early HR-positive/HER2-negative breast cancer, published in JNCI, refining risk stratification criteria for adjuvant abemaciclib/ribociclib eligibility (monarchE vs NATALEE criteria). Findings could help clinicians better identify which node-positive patients derive the greatest prognostic benefit from adjuvant CDK4/6 inhibitor therapy.

Small phase 1 pharmacokinetic and safety study of the oral PROTAC estrogen receptor degrader vepdegestrant in Chinese patients with pretreated ER+/HER2- advanced breast cancer, published in Cancer Chemother Pharmacol, confirming tolerability and preliminary activity consistent with prior Western/Japanese cohorts.

Preclinical study in triple-negative breast cancer models (with in silico correlation to melanoma immunotherapy cohorts), published in J Immunother Cancer, showing methylglyoxal stress drives MDSC expansion and metastasis and that scavenging it may enhance anti-PD-1 efficacy. Mechanistic/preclinical work without direct clinical outcome data, informing future combination strategies rather than immediate practice.

Retrospective genomic and clinicopathologic comparison in JCO Precision Oncology distinguishing primary breast neuroendocrine carcinoma from breast cancer with neuroendocrine differentiation. Highlights distinct molecular features (RB loss, TP53 alterations) and poor response to neoadjuvant chemotherapy, informing prognosis but not a specific targeted therapy decision.