BackgroundLoco-regional recurrences (LRR) following breast-conserving surgery (BCS) remain a heterogeneous class of disease that has significant variation in its biological behavior and prognosis.MethodsTo delineate the spatiotemporal patterns of LRR after BCS, we analyzed the data of 4325 patients treated with BCS from 2006 to 2016. Clinico-pathological and treatment specific factors were analyzed using the Cox proportional hazards model to identify factors predictive for LRR events. Recurrence patterns were scrutinized based on recurrence type and recurrence-free interval (RFI). Annual recurrence rates (ARR) were compared according to recurrence type and molecular subtype.ResultsWith a median follow-up of 66 months, 120 (2.8%) LRRs were recorded as the first site of failure. Age, pathologic stage, and molecular subtype were identified as predictors of LRR. The major recurrence type was ipsilateral breast tumor recurrence, which mainly (83.6%) occurred ≤5y post surgery. In the overall population, ARR curves showed that relapse peaked in the first 2.5 years. Patients with regional nodal recurrence, shorter RFI, and synchronous distant metastasis were associated with a poorer prognosis. HER2-positive disease had a higher rate of LRR events, more likely to have in-breast recurrence, and had an earlier relapse peak in the first 2 years after surgery.ConclusionsLRR risk following BCS is generally low in Chinese ethnicity. Different recurrence patterns after BCS were related to distinct clinical outcomes. Management of LRR should be largely individualized and tailored to the extent of disease, the molecular profile of the recurrence, and to baseline clinical variables.

We developed a nomogram to predict the probability of ACR in breast cancer patients with intermediate RS. This model may aid the individual risk assessment and guide treatment decisions in clinical practice.

Objective: Sentinel lymph node biopsy (SLNB) is currently the standard of care in clinically node negative (cN0) breast cancer. The present study aimed to evaluate the negative predictive value (NPV) of 18F-FDG dedicated lymph node positron emission tomography (LymphPET) in cN0 patients. Methods: This was a prospective phase II trial divided into 2 stages (NCT04072653). In the first stage, cN0 patients underwent axillary LymphPET followed by SLNB. In the second stage, SLNB was omitted in patients with a negative preoperative axillary assessment after integration of LymphPET. Here, we report the results of the first stage. The primary outcome was the NPV of LymphPET to detect macrometastasis of lymph nodes (LN-macro). Results: A total of 189 patients with invasive breast cancer underwent LymphPET followed by surgery with definitive pathological reports. Forty patients had LN-macro, and 16 patients had only lymph node micrometastasis. Of the 131 patients with a negative LymphPET result, 16 patients had LN-macro, and the NPV was 87.8%. After combined axillary imaging evaluation with ultrasound and LymphPET, 100 patients were found to be both LymphPET and ultrasound negative, 9 patients had LN-macro, and the NPV was 91%. Conclusions: LymphPET can be used to screen patients to potentially avoid SLNB, with an NPV > 90%. The second stage of the SOAPET trial is ongoing to confirm the safety of omission of SLNB according to preoperational axillary evaluation integrating LymphPET.