Between evidence and fear of recurrence: decision-making in adjuvant treatment of a ypT1aN0 case after neoadjuvant therapy. Are we ready to forgot treatment?

Introduction: The incorporation of neoadjuvant immunotherapy has modified the therapeutic approach to resectable nonsmall cell lung cancer. However, the indication for adjuvant treatment in patients with a major pathological response remains an area of uncertainty. Case presentation: A 66-year-old former smoker with a history of hypertension, dyslipidemia, and IgA nephropathy was diagnosed with pulmonary squamous cell carcinoma (PD-L1: 70%), staged as cT1aN2M0 (stage IIB) due to a hypermetabolic right paratracheal mediastinal lymph node. The patient received neoadjuvant treatment with carboplatin, paclitaxel, and nivolumab (CheckMate 816 regimen). After three cycles, a complete metabolic nodal response was observed. Right upper lobectomy with lymphadenectomy was performed, revealing minimal residual adenocarcinoma with lepidic and acinar patterns, without residual squamous cell carcinoma or lymph node involvement (ypT1aN0, R0). Discussion: This case highlights the histological discordance between the initial biopsy and the surgical specimen, suggesting tumor heterogeneity or a possible synchronous double primary tumor. However, the main clinical challenge lies in the decision regarding adjuvant treatment in patients with a major pathological response after neoadjuvant chemoimmunotherapy and low-risk final staging, where the available evidence remains limited. Conclusions: The indication for adjuvant treatment after neoadjuvant chemoimmunotherapy remains an area of uncertainty, particularly in patients with a major pathological response. Treatment individualization and consideration of participation in clinical trials are essential