Pathological complete necrosis after pulmonary thermal ablation: a systematic review and meta-analysis of ablate-and-resect studies.

BACKGROUND: Thermal ablation is increasingly used for pulmonary tumors, but treatment success is generally assessed by imaging rather than direct histopathology. Ablation-followed-by-resection studies provide direct evidence of residual viable tumor after ablation. RESEARCH QUESTION: What is the rate of pathologically confirmed complete tumor necrosis after pulmonary thermal ablation, and which methodological or biological factors influence this outcome? STUDY DESIGN AND METHODS: A systematic search of PubMed, Embase, and Web of Science (2005-2025) yielded 8 ablate-and-resect studies with 95 evaluable lesions. The primary analysis used a generalized linear mixed model (GLMM). The subgroups were sorted according to pathological assessment stringency, resection time, tumor type and ablation procedure. RESULTS: The pooled complete necrosis rate was 71.4 % (95 % CI 40.1 %-90.3 %), with significant between-study heterogeneity (likelihood-ratio p < 0.0001) and a wide 95 % prediction interval (4.0 %-99.3 %). A Freeman-Tukey sensitivity analysis yielded a similar estimate of 69.0 %. Complete-necrosis rates varied numerically by pathological assessment (55.6 % vs 81.7 %), resection timing (61.1 % vs 79.7 %), tumor type (44.3 % vs 81.1 %), and ablation modality, but none of the subgroup differences was statistically significant. INTERPRETATION: Pathologic complete necrosis after pulmonary thermal ablation varies substantially across ablate-and-resect studies and is influenced by both treatment context and pathological assessment. The pooled estimate should therefore be interpreted as a descriptive summary of a heterogeneous evidence base rather than as a benchmark for contemporary definitive ablation.