Operation, chemotherapy and radiotherapy are typical treatments of lung cancer today. Curative tumor resections are still the mainstream treatment for early-stage small peripheral lung cancer. However, non-surgical treatments such as trans-bronchoscopy ablation, including bronchoscopy microwave ablation and bronchoscopy PDT, are also potential options.
Several ongoing clinical trials have revealed that using electro-magnesium bronchoscopy (EMB) system in hybrid OR suit is feasible when performing PDT. Although having technique difficulties, repeating bronchoscopy PDT per operation is also conceivable for larger tumor. However, the diameter of light penetration is still around 1.5 cm, which limits the widely use of PDT treatment for peripheral lung tumor.
In 2009, Dr. Friedberg injected castor oil into the bronchus and the result was very similar as using optic fiber. But castor oil is not suitable for clinical practice due to severe lipoid pneumonia complication.
It is found in our study that Lipiodol (FDA-approved) could replace Castor oil as the light diffusor agent. The refractive index (1.49) is similar to castor oil (1.47). We also found that dissolving Indole-3-acetic acid (IAA) in Lipiodol could create a new drug, which can be used as light scattering agent and oxidant as a novel photodynamic therapy method.
We have run a pig model to test this theory. The living pig was sacrificed after 1 month and lung injury condition pathology examination prove that no significant injury is noted even at the maxima light energy level(800J). The feasibility of our novel method has been proved and needed further studies.
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