A new 3D cell culture method for malignant pleural mesothelioma (MPM) was developed. Erlotinib increases the direct cytotoxicity of Photofrin-mediated PDT without altering Photofrin uptake. The 3D model is suitable for further analysis such as flow cytometry. Potential use of receptor tyrosine kinase inhibitors to improve clinical PDT response. Here, NTRK1 is linked to malignant pleural mesothelioma.