Pathologic Complete Response (pCR) Rate and Predictors of Response to Taxane, Trastuzumab, and Pertuzumab in HER2‑Positive Breast Cancer: Secondary Analyses of EA1181/CompassHER2 pCR
PURPOSE EA1181 (ClinicalTrials.gov identifier: NCT04266249 ) is a single-arm trial evaluating neoadjuvant taxane, trastuzumab, and pertuzumab (THP) in patients with clinical stage II/IIIa human epidermal growth factor receptor 2 (HER2)–positive breast cancer. This report focuses on the secondary end points of pathologic complete response (pCR) rates and associated factors. The primary end point—3-year recurrence-free survival among patients achieving a pCR (ypT0/Tis, ypN0)—will be reported when data mature. METHODS Patients received four cycles of trastuzumab and pertuzumab (HP) with either once per week paclitaxel (12 weeks) or docetaxel (every 3 weeks for four cycles), followed by surgery. Clinicopathologic characteristics were assessed in all patients. The HER2DX pCR score was determined using diagnostic biopsy samples in a representative subset. Logistic regression models identified factors associated with pCR. RESULTS A total of 2,175 patients were enrolled (781 HER2+/estrogen receptor‑negative [ER–]; 1,394 HER2+/ER+). Of 2,141 patients who initiated THP, the overall pCR rate was 43.8%: 63.7% in HER2+/ER– and 32.4% in HER2+/ER+ tumors. Higher pCR rates were observed in tumors that were ER-negative or low ER expressing, progesterone receptor-negative or low expressing, HER2 immunohistochemistry (IHC) 3+, and in patients treated with once per week paclitaxel. T3 disease was associated with a lower pCR rate in HER2+/ER– tumors; otherwise, tumor (T) and nodal (N) stage did not significantly affect pCR. Among 569 patients assessed for HER2DX pCR scores, a high score was independently associated with higher pCR rates, after adjustment for clinicopathologic variables. CONCLUSION Neoadjuvant THP achieved pCR in nearly two-thirds of patients with HER2+/ER– and one third with HER2+/ER+ breast cancer. Low hormone receptor expression, HER2 IHC 3+ status, once per week paclitaxel use, and a high HER2DX pCR score were independent predictors of pCR. These findings should help optimize risk stratification and treatment personalization for patients with HER2-positive breast cancer.
American Radium Society (ARS) Appropriate Use Criteria (AUC) for Low-Dose Radiotherapy for Treatment of Osteoarthritis
Objectives: To summarize current evidence for radiotherapy in the treatment of OA. The population, intervention, comparator, and outcome questions included: What is the role of LDRT for treatment of OA?; What are risks of LDRT?; and What are the optimal RT techniques for OA? Methods: This multispecialty-led committee includes radiation oncologists, rheumatologists, orthopedic surgeons, and a patient advocate. Using the population, intervention, comparator, outcome, timing and study design (PICOTS) framework, evidence regarding treatment outcomes was assessed using Cochrane and PRISMA methodology. Eligible studies included prospective and retrospective (n≥50) studies published between January 1, 2010, and May 10, 2025, from Embase, Medline, and PubMed databases. Study type and quality were assessed. Well-established RAND-UCLA consensus methodology (modified Delphi) was used to rate the appropriateness of the treatment options. Results: Of the 548 articles identified using the search strategy, 44 were selected for inclusion. Eight additional studies were identified through backward citation searching. Ten well-designed studies accounting for biases, 15 moderately well-designed studies accounting for the most common biases, 18 studies with design limitations, 8 supplemental studies not useful as primary evidence, and 1 meta-analysis were included. Additional studies were included to provide context and were not used to guide recommendations. The results of this analysis demonstrate that LDRT results in an overall treatment response rate of 60% to 90%, with significant clinical benefits including pain reduction, increased joint mobility, and improved quality of life. Conclusions: This systematic review and consensus guidelines for LDRT treatment of OA are based on current evidence. Further high-quality studies are warranted.
Revisiting Combined Modality Therapy in Older Patients With Luminal Breast Cancer Through the Patient Lens