Radiation Oncology — Weekly Evidence Brief

Recent advancements in radiotherapy techniques are reshaping treatment paradigms across various cancer types. For medically inoperable central and ultracentral non-small cell lung cancer (NSCLC), an institution-specific hypofractionated regimen demonstrated good local control and acceptable toxicity, with 1-year local control rates reaching 93.5% 1. In pancreatic cancer, modern radiotherapy techniques like SBRT, IMRT, and PBT offer similar 2-year overall survival, with SBRT showing a significantly lower rate of acute hematologic toxicity compared to other modalities 2. For brain metastases, hypo-fractionated stereotactic radiosurgery (HySRS) delivers high radiation doses over 2-5 fractions, mitigating toxicity while maintaining high local control, especially for larger lesions 3. This approach allows for effective local treatment where systemic therapies often have limited intracranial efficacy 3.

Personalizing cancer treatment through risk stratification and biomarker identification is a growing focus. For ypN0 breast cancer patients after neoadjuvant chemotherapy, a recurrence risk score model identified high-risk subgroups who benefited from postmastectomy radiotherapy (PMRT) in terms of locoregional control, while low-risk patients showed no benefit 4. In oligometastatic NSCLC, integrating local therapy, particularly radiotherapy, into systemic treatment regimens has shown improved progression-free and overall survival in carefully selected patients, emphasizing the role of biomarker status and metastasis distribution in treatment choice 5. For advanced head and neck cancer, algorithm-based chemoradioselection (CRS) represents a promising method to optimize treatment intensity, personalize therapy, and minimize overtreatment 6. Furthermore, in rectal cancer, tumor cell density (TCD) shows potential as a prognostic and predictive biomarker for response to neoadjuvant short-course radiotherapy 7.

Artificial intelligence (AI) and advanced imaging are enhancing precision in cancer management. A deep learning-based model has shown significant improvements in predicting Gamma Knife plan quality metrics for brain metastases, offering a tool for objective quality control and optimization 8. For esophageal squamous cell carcinoma, an AI-based machine learning model demonstrated an AUC of 0.85 for predicting pathological complete response (pCR) to chemoradiotherapy, with predicted pCR-positive patients showing significantly better relapse-free survival 9. Moreover, PSMA-PET-guided intensification of salvage radiotherapy after radical prostatectomy significantly improved failure-free survival without increased toxicity, particularly benefiting patients with higher PSA levels 10. In hepatocellular carcinoma, microbubble-based radiosensitization combined with 90Y-TARE significantly improved treatment response and prolonged overall survival, suggesting a new adjunct therapy 11.

The integration of immunotherapy and refined surgical strategies is expanding treatment options for challenging cancers. For initially unresectable non-small cell lung cancer (NSCLC), salvage surgery following chemo-immunotherapy achieved a 100% complete resection rate with no major complications and promising 3-year progression-free and overall survival rates 12. The introduction of immune checkpoint inhibitors (ICIs) has also significantly improved overall survival for lung cancer patients with brain metastases, with notable benefits observed in squamous cell and small cell carcinoma subtypes 13. Real-world data comparing perioperative chemotherapy (FLOT) and preoperative concurrent chemoradiotherapy (CROSS) for localized esophageal and esophagogastric junction adenocarcinoma suggests CROSS may lead to higher treatment completion rates, pathological tumor downstaging, and complete pathological response, despite similar overall survival 14.