The role of pulmonary metastasectomy (PM) for non-primary lung cancer: Umbrella review of meta-analyses

Introduction: Due to heterogeneous characteristics of primary cancers, the efficacy of pulmonary metastasectomy(PM) in non-primary lung cancers has not been investigated other than colorectal cancers. This study aims to investigate the clinical outcomes of PM for non-primary lung cancer. Methods: A systematic search for meta-analyses on PM for non-primary lung cancers was conducted, encompassing publications up to January 3, 2024. The analysis included seven primary cancer types: renal cell, breast, adrenocortical, head and neck cancers, melanoma, germ cell tumors, and sarcoma. Primary outcomes, overall survival, and recurrence rates post-PM were assessed using random-effect models to account for study heterogeneity. Results: This study included 16 systematic-review articles and 101 individual studies, involving 10,277 patients who underwent PM for non-primary lung cancer. Patients had a mean age of 48.0 years, with 68.4% being male. About half of the patients(47.1% [95%CI 40.8-53.5] presented with multiple metastatic lesions, and complete R0 resection achieved in 87.2% [95%CI 83.0-90.8]. The pooled 5-year overall survival (OS) rate post-PM was 41.2% [95%CI, 37.1-45.4%]. Patients with germ cell tumors demonstrated significantly higher survival rate than other cancers(p<0.05), while patients with melanoma exhibited the poorest outcome(p<0.05). During follow-up, 57.6%[95%CI 46.4-68.1] had recurrence; 48% of them had intrathoracic-only recurrence and 52% had extra-thoracic recurrence. Conclusion: This study underscores the survival benefits associated with PM. Overall survival rates following PM do not significantly differ based on primary cancer types, except for germ cell tumors and melanoma. These findings highlight the importance of recognizing and incorporating PM into clinical practice when appropriate. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors