Photo Credit: Nattakorn Maneerat

The following is a summary of “Nodal Burden and Oncologic Outcomes in Patients With Residual Isolated Tumor Cells After Neoadjuvant Chemotherapy (ypN0i+): The OPBC-05/ICARO Study,” published in the November 2024 issue of Oncology by Montagna et al.  

For patients with breast cancer, sentinel lymph node (SLNs) status after neoadjuvant chemotherapy (NAC) ypN0(i+) is not well understood in terms of additional nodal involvement.  

Researchers conducted a retrospective study investigating the rate of additional positive lymph nodes and oncologic outcomes in patients with isolated tumor cells (ITCs) in SLNs after NAC- ypN0(i+).  

They analyzed data from 583 patients with stage I to III breast cancer and ITCs in SLNs after NAC across 62 centers in 18 countries. The primary endpoint was the 3-year rate of any axillary recurrence, with the secondary endpoint being the rate of any invasive recurrence.  

The results showed that of 583 patients,182 (31%) had completed axillary lymph node dissection (ALND), and 401 (69%) did not, with a median age of 48 years. Most patients (74%) were clinically node-positive (cN+) at diagnosis, and 41% had hormone receptor-positive (HR+)/human epidermal growth factor receptor 2–negative (HER2−) tumors. The mean number of SLNs with ITCs was 1.2. Patients treated with ALND were more likely to present with clinical node-positive disease (cN2/3) at diagnosis (17% vs. 7%, P<.001), have ITCs detected on frozen section (62% vs. 8%, P<.001), have lymphovascular invasion (LVI) (38% vs. 24%, P<.001), and receive adjuvant chest wall (89% vs. 78%, P=.024) and nodal radiation (82% vs. 75%, P=.038). Additional positive nodes were found at ALND in 30% of patients, but only 5% had macrometastases. The 3-year axillary and invasive recurrence rates were 2% (95% CI, 0.95% to 3.6%) and 11% (95% CI, 8% to 14%), respectively, with no statistical difference by type of axillary surgery.  

They concluded that the nodal burden in patients with ypN0(i+) was low, and axillary recurrence after omission of ALND was rare routine ALND in all patients with ypN0(i+) was not supported.  

Source: ascopubs.org/doi/10.1200/JCO.24.01052