Abstract 610P
Background
Although MPR or PCR rates reached a very high level after neoadjuvant treatment, 2y-EFS could only be maintained at 63-77%.
Methods
We retrospectively collected 116 real-world single-center patients who completed surgery after neoadjuvant immunotherapy and had survival information.
Results
The overall 2-year PFS rate was 77.59% (90/116), with MPR and non-MPR rates at 85.51% and 65.96%, respectively. Of these, 8 MPR cases experienced local recurrences, while 2 presented with distant metastases. Conversely, among non-MPR cases, 10 manifested local recurrences, with 6 encountering distant metastases. Given that the relapsed cohort has typically undergone a specified period of postoperative adjuvant chemoimmunotherapy or immunotherapy alone as established clinical trial protocols, we stratified the entire patient population based on ypN negative and positive status. Particularly, ypN(+) patients exhibited a markedly elevated likelihood of postoperative recurrence compared to ypN(-)(30.61% vs 11.70%), a trend also accentuated within the MPR population(25.00% vs 7.81%) (P=.0204* and P=.0383*), while no significant discrepancy was discerned in the non-MPR cohort (34.48% vs 20.00%).
Conclusions
The presence of residual positive lymph nodes in MPR patients indicates an increased tumor burden and a higher risk of recurrence. Conversely, non-MPR patients with inadequately controlled primary tumors may experience reduced impact from lymph node status. The higher recurrence rate in ypN(+) cases, due to suboptimal lymph node removal during surgery, underscores the latent risk posed by overlooked lymph nodes as potential metastatic sites. The imperative of postoperative adjuvant radiotherapy thus arises. In the absence of minimal residual disease (MRD) guidance, postoperative adjuvant radiotherapy targeted at the lymphatic drainage area emerges as a compelling option for patients failing to achieve MPR post-neoadjuvant induction therapy and retaining positive lymph nodes post-surgical dissection.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
X. Tan.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.