Abstract
BACKGROUND: Hormone receptor-positive, HER2-negative (HR + /HER2-) breast cancer generally has a favorable prognosis; however, early postoperative recurrence markedly reduces survival. Accurate prediction of early recurrence is crucial for personalizing treatment. This case-control study compared MammaPrint (MP) and BluePrint (BP) results between early recurrence patients and matched controls. METHODS: Patients were selected from our previous study, the WJOG15721B cohort (n = 2732). Those with recurrence within three years after surgery were randomly extracted, and controls matched for institution, clinical stage, and number of pathological lymph node metastases were included (n = 124). Tumor samples underwent MP and BP assays to classify recurrence risk and molecular subtypes. RESULTS: Of 115 submitted tumor samples, 85 were analyzed successfully (43 early recurrence, 42 no recurrence). High-risk MP classification was significantly more frequent in early recurrence patients (79.1% vs. 40.5%, p < 0.001), and Luminal B BP subtype was more common in early recurrence patients (79.1% vs. 38.1%, p < 0.001). High MP risk was associated with high Ki-67 levels and higher nuclear grade. Integrating clinical and genomic risk enhanced prognostic precision: patients with both clinical and genomic high risk had the highest recurrence rate (100%), those with low clinical and genomic risk had the lowest (28.1%), and patients with low clinical but high genomic risk showed an intermediate recurrence rate (57.5%). CONCLUSIONS: Compared with patients without recurrence, those with early recurrence showed a significantly higher prevalence of high-risk MP results and Luminal B BP subtype. High-risk MP/Luminal B BP subtype suggested an association with early recurrence in patients with HR + /HER2- early breast cancer.