Radiomic subtypes predict survival and chemotherapy benefit in stage I lung adenocarcinoma: a multicenter study

Postoperative survival outcomes vary substantially among patients diagnosed with stage I lung adenocarcinoma (LUAD). This study aimed to develop CT-based radiomic subtypes using unsupervised clustering to assess their association with overall survival (OS), systemic nutritional-inflammatory status, and adjuvant chemotherapy benefit.

A total of 496 stage I LUAD patients from two independent centers were included. Preoperative CT radiomic features (n = 1218) were extracted, and subtypes were derived using the K-means clustering algorithm. The independent prognostic value of these subtypes, along with their capacity to predict the benefit of adjuvant chemotherapy, was evaluated through multivariable Cox regression and treatment-by-subtype interaction analyses.

Three radiomic subtypes with significant prognostic differences in OS were identified. The high-risk subtype, Cluster 2, exhibited distinct clinical characteristics and was associated with markedly poorer OS (hazard ratio [HR] = 15.71, p < 0.001, compared to Cluster 0). Cluster 2 also showed an inflammatory imbalance, with elevated systemic immune-inflammation index and neutrophil-to-lymphocyte ratio, and  a decreased lymphocyte-to-monocyte ratio. Notably, a significant interaction was found between subtypes and adjuvant chemotherapy (interaction p < 0.001, Cluster 2 vs Cluster 0). Subgroup analysis indicated that stage IB patients within Cluster 2 derived a significant survival benefit from adjuvant chemotherapy (interaction p = 0.003 vs Cluster 0).

This study developed a CT-based radiomic subtype system using unsupervised clustering that identifies high-risk stage I LUAD patients with systemic inflammatory imbalance. Notably, these subtypes predict differential survival benefits from adjuvant chemotherapy in high-risk stage IB patients, thereby supporting personalized postoperative treatment strategies.

This CT-based radiomic subtype system stratifies prognosis and identifies stage I LUAD patients who may benefit from adjuvant chemotherapy, enabling personalized treatment decisions in radiology.

Conventional tumor-node-metastasis (TNM) staging does not adequately capture tumor heterogeneity in stage I LUAD. Three CT-based radiomic subtypes were established, with the high-risk subgroup correlating with systemic inflammatory imbalance and poorer OS. CT-based radiomic stratification identifies stage IB patients who benefit from adjuvant chemotherapy, supporting personalized postoperative management.