Surgical resection for pulmonary metastases from head and neck adenoid cystic carcinoma: a propensity-matched survival analysis

The management of pulmonary metastases (PM) from head and neck adenoid cystic carcinoma (ACC) remains controversial, with limited evidence guiding the choice between surgical and non-surgical strategies. This study aimed to compare long-term survival outcomes between patients undergoing surgical resection and those receiving non-surgical management for ACC-derived PM.

We conducted a retrospective analysis of 204 patients with pulmonary metastases from head and neck ACC treated at our institution between January 2010 and December 2024. Patients were categorized into Surgery (n = 108) and Non-Surgery (n = 96) groups. To address selection bias and improve causal inference in this observational study, propensity score matching (PSM) was performed based on key clinical variables, generating 68 well-matched pairs. Overall survival (OS) and progression-free survival (PFS) were compared using Kaplan-Meier analysis and Cox proportional hazards models.

Before matching, the Surgery group demonstrated significantly higher 5-year OS (97.73% vs. 84.2%, P = 0.0004) and PFS (89.39% vs. 74.66%, P = 0.021). After PSM, the survival advantage persisted, with the Surgery group showing improved 5-year OS (95.75% vs. 82.91%, P = 0.0063) and PFS (86.93% vs. 73.86%, P = 0.0039). Multivariate analysis confirmed surgical resection as an independent prognostic factor for improved OS (HR = 0.08, 95% CI: 0.01–0.42, P = 0.0032), alongside tumor grade, presence of pleural effusion, and International Registry of Lung Metastases (IRLM) stage.

In this propensity-matched analysis, surgical metastasectomy was associated with significantly improved survival in selected patients with ACC lung metastases, supporting its consideration as a valuable therapeutic option for oligometastatic disease within a multidisciplinary framework.