Work

Transbronchial photodynamic therapy for peripheral lung cancer – A pilot study

Year: 2026

Type: article

Abstract: • Introduces a novel lipiodol-assisted transbronchial light delivery method that induces a fiber-optic effect to expand PDT illumination in peripheral lung malignancies. • Demonstrates the technical feasibility and acute safety of both single and multiple illumination strategies under hybrid operating room guidance. • Achieves complete lipiodol encapsulation and successful PDT delivery in all patients without major complications such as pneumonia or lung injury. • Shows pathological tumor necrosis and partial responses, suggesting biological efficacy even at low light dose (200 J/cm). • Provides the foundation for upcoming Phase I–II trials to optimize light dose and evaluate long-term therapeutic outcomes Photodynamic therapy (PDT) is an established treatment for centrally located early-stage lung cancer but remains limited for peripheral lung cancers due to restricted light penetration and the difficulty of precisely positioning optical fibers. Our team developed a novel light delivery technique involving the transbronchial infusion of Lipiodol to induce a waveguide effect, expanding the illumination field. We conducted two sequential pilot clinical trials to evaluate the feasibility and safety of this approach. Two single-arm, Phase-0 feasibility studies were conducted. Eligible patients had peripheral lung malignancies (≤2 cm in Stage I; ≤3 cm in Stage II) and were unsuitable for or refractory to standard therapies. In Stage I, an electromagnetic navigation bronchoscope (ENB) was used to position a catheter for Lipiodol infusion and single-illumination PDT. Stage II employed an ultrathin bronchoscope to access multiple peripheral airways for repeated Lipiodol infusion and illumination from 3–6 angles. The primary endpoints were technical feasibility and safety (specifically lipoid pneumonia or hemoptysis). Six patients (three in each stage) were treated. Diagnoses included primary adenocarcinoma and metastatic lesions. All procedures were technically successful with complete Lipiodol encapsulation confirmed by cone-beam CT. No major acute complications occurred. Tumor response at 3 months varied: in Stage I, two patients had progressive disease (PD) and one had stable disease (SD); in Stage II, one PD, one partial response (PR), and one SD were observed. Lipiodol was gradually absorbed within 3–6 months. Lipiodol-assisted transbronchial PDT is technically feasible and demonstrated a favorable acute safety profile in this small pilot cohort. While the low light dose (200 J/cm) resulted in modest tumor control, the technique successfully addressed the challenge of light delivery to peripheral lesions. Future Phase I trials with dose escalation are warranted.

Source: Photodiagnosis and Photodynamic Therapy

DOI: 10.1016/j.pdpdt.2026.105398