Radiation Oncology — Weekly Evidence Brief

Recent advancements emphasize personalized treatment approaches and predictive modeling across various solid tumors. In breast cancer, quantitative ultrasound (QUS) machine learning models accurately predict neoadjuvant chemotherapy response at week 4, showing 92% accuracy and high specificity, which could guide adaptive treatment modification 1. For bladder cancer, a non-invasive MRI-based deep learning model (MF-DLM) effectively predicts overall survival, outperforming pathological T stage and identifying patients who benefit most from adjuvant therapy 2. Similarly, a CT radiomics model demonstrates high accuracy in predicting prognosis for nasopharyngeal carcinoma patients after intensity-modulated radiation therapy 3. These AI-driven strategies promise to optimize individualized treatment plans by enabling earlier identification of responders and non-responders, as highlighted by a comprehensive review on AI in neoadjuvant immunotherapy prediction 4.

Optimizing systemic and locoregional therapies continues to refine cancer management. For resectable non-small cell lung cancer (NSCLC), two cycles of neoadjuvant immunochemotherapy show comparable pathological complete response, major pathological remission, and long-term survival rates to three cycles, without increased toxicity 5. This suggests a potential reduction in treatment burden. However, for advanced NSCLC with PDL1 ≥50%, pembrolizumab plus chemotherapy was not associated with improved survival compared to pembrolizumab alone, and may even lead to shorter restricted mean survival times in some subgroups, possibly due to increased toxicity 6. In contrast, a real-world study found that first-line third-generation EGFR-TKIs combined with chemotherapy demonstrated favorable objective response rates and progression-free survival benefits in advanced EGFR-mutant NSCLC 7. Furthermore, combining neoadjuvant ipilimumab/nivolumab with chemoradiotherapy in NSCLC patients robustly enhanced type I immune responses and T-cell infiltration in tumor-draining lymph nodes 8.

Tailored treatment strategies are also emerging for challenging tumor types. In IDH wild-type and TERT promoter mutation histological grade 2/3 gliomas, chemoradiotherapy significantly improved overall and progression-free survival compared to radiotherapy alone, with a favorable safety profile 9. For de novo metastatic nasopharyngeal carcinoma (dmNPC) patients, a failure-pattern-based risk stratification model suggests that locoregional radiotherapy (LRRT) significantly improves 2-year progression-free survival only in partial responders prone to isolated locoregional progression, while durable responders and resistant patients may safely omit LRRT 10. Understanding treatment efficacy in specific contexts is further aided by new evaluation metrics; for extensive-stage small cell lung cancer, restricted mean survival time and restricted mean time lost offer valuable, clinically intuitive insights into immune checkpoint inhibitor efficacy, particularly when proportional hazards assumptions are violated 11.

Advances in local control and response assessment are also significant. For intracranial meningiomas, long-term follow-up reveals a second recurrence peak between 7 and 10 years after subtotal resection, with adjuvant Gamma Knife radiosurgery significantly lowering recurrence risk 12. In colorectal cancer with lung metastases, local control treatments like surgery, stereotactic body radiation therapy, and image-guided thermal ablation demonstrate significant survival benefits for oligometastatic disease 13. Moreover, for well-differentiated grade 1/2 neuroendocrine tumors, new Response Evaluation Criteria in Neuroendocrine Tumors (RECIN) integrate SSTR-PET parameters with CT metrics, showing improved response identification and prediction of progression-free survival compared to standard RECIST 14. Finally, for primary lymph node-positive prostate cancer, radical prostatectomy combined with PSMA-radioguided lymph node dissection is associated with longer treatment-free survival 15.