Clinical Characteristics and Treatment Outcomes of Primary Pulmonary Salivary Gland-Type Tumors

다국어 초록 (Multilingual Abstract)

Background: Primary pulmonary salivary gland-type tumors (PSGTs) are rare neoplasms that often arise in the central airways. Because treatment selection is largely stage-driven, we described stage-stratified clinicopathologic features, treatment patterns, and survival outcomes, and explored the role of bronchoscopic intervention in selected early-stage, airway-confined tumors.
Methods: We retrospectively reviewed patients with pathologically confirmed PSGTs diagnosed between 2003 and 2023 at a tertiary center. Patients were primarily analyzed by clinical stage (I-II vs III-IV). Initial definitive local treatment was also recorded as surgery (n = 20), bronchoscopic intervention (BFS; n = 4), or radiotherapy/chemoradiotherapy (RT/CRT; n = 5). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Exploratory univariable Cox regression was performed to assess prognostic factors, acknowledging confounding by indication for treatment modality.
Results: Twenty-nine patients were included; 69.0% had mucoepidermoid carcinoma and 27.6% had adenoid cystic carcinoma. Most patients had stage I-II disease (75.9%), whereas all patients in the RT/CRT group had stage III-IV disease with larger tumors. Survival differed substantially by stage: stage I-II disease showed excellent outcomes with median OS and PFS not reached, while stage III-IV disease had markedly worse outcomes. In an exploratory three-group analysis by treatment modality, the surgery and BFS groups showed overlapping KM curves with median OS and PFS not reached, whereas the RT/CRT group had poorer outcomes (median OS 19.5 months; median PFS 10.1 months), reflecting its exclusive use in advanced-stage disease (global log-rank p < 0.001 for both endpoints).
Conclusions: Clinical stage strongly influences both treatment selection and outcomes in PSGTs. Surgical resection remains the preferred curative treatment when feasible. In a small, highly selected cohort of early-stage, airway-confined tumors, bronchoscopic intervention was associated with favorable long-term outcomes, warranting further study. RT/CRT was used predominantly in advanced disease and was accompanied by poor prognosis, underscoring the importance of early diagnosis and appropriate local therapy selection.

목차 (Table of Contents)

• Summary i
• List of tables v
• List of figures vi
• Introduction 1
• Methods 2
• Results 6
• Discussion 17
• Conclusion 20
• References 21
• Korean summary 23