Microwave ablation vs. radiotherapy: which Non-Surgical option works best for early lung cancer?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * 1\. Adults aged 18 years or above. 2. Clinically stage IA NSCLC suitable for definitive local therapy, defined as T1N0M0 with maximum tumour diameter 3 cm or less, based on routine staging work up and multidisciplinary team review. 3\. Pathological confirmation of NSCLC by histology or cytology whenever feasible. If tissue confirmation is not feasible or poses unacceptable risk, eligibility may be allowed after multidisciplinary consensus that imaging and clinical features are highly consistent with primary lung cancer, consistent with SBRT guidance for selected unbiopsied cases. 4\. Medically inoperable status, or patient declines surgery after multidisciplinary discussion, and both navigation bronchoscopy-guided microwave ablation and SBRT are considered acceptable treatment options by the treating teams (clinical equipoise). 5\. Target lesion technically suitable for both modalities, including feasibility and safety for bronchoscopy-based ablation and suitability for SBRT planning and delivery. 6\. Willing and able to provide informed consent and accept random assignment to either navigation bronchoscopy guided microwave ablation or SBRT, and able to comply with the follow up schedule. Exclusion Criteria: * 1\. Evidence of lymph node involvement (N1 or higher) or distant metastases (M1) on routine staging. 2\. Multiple synchronous primary lung cancers requiring different local strategies, or inability to define a single index lesion for primary endpoint assessment. 3\. Prior thoracic radiotherapy that would overlap the planned SBRT field, or prior local therapy to the index lesion. 4\. Another active malignancy that is likely to confound outcome assessment (for example, malignancy requiring systemic therapy or expected to limit 2-year survival), except adequately treated non melanoma skin cancer or in situ carcinoma with negligible recurrence risk. 5. Contraindications to bronchoscopy sedation or anaesthesia that preclude RAB or ENB guided ablation, or medical conditions that preclude SBRT positioning or safe delivery. 6\. Lesions judged unsafe or technically infeasible for either modality (for example, proximity to critical structures beyond predefined safety limits), as determined by the procedural and radiation oncology teams. 7\. Pregnant or breastfeeding women. 8. Inability or unwillingness to comply with study procedures or follow up.