Intrapleural Photodynamic Therapy in a Multimodal Treatment for Patients With Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive tumour with poor prognosis (median survival \<13 months), and high resistance to chemotherapy. Extended pleurectomy/decortication (eP/D) is a debulking surgery of MPM but cannot be considered as a curative treatment. Therefore it has been suggested that eP/D may be of interest if combined with intra-operative treatment and adjuvant therapies. Photodynamic Therapy (PDT) is an innovative treatment based on the rationale that tumour cells, if previously treated with photosensitizing drugs (Photofrin), will die when exposed to light at a particular wavelength. Interestingly PDT might also stimulate anti-tumour immune response through the release of tumour antigens and induced inflammation. PDT was tested in phase I-II trials for MPM in combination with EPP or eP/D, and chemotherapy. US studies from J Friedberg et al found very promising survival results in MPM when combining eP/D, but not EPP, intra-operative PDT and chemotherapy (cisplatin-pemetrexed), with a median overall survival of 31.7 months. However, the definitive value of intra-pleural PDT combined to eP/D in the treatment of MPM still need to be validated. The same multimodal treatment has been established in Lille, the French national expert centre for MPM, with the help of our american colleagues. Therefore, this phase II trial proposes to patients to benefit from the combination of eP/D, intra-operative PDT then chemotherapy by cisplatin-pemetrexed and prophylactic radiotherapy. Primary endpoint is the feasibility for the patients to have the full multimodal treatment of MPM including intrapleural PDT without unacceptable or unexpected grade III-IV toxicities. Secondary endpoints are PFS, OS, ORR, and quality of life. If the feasibility of such treatment would be confirmed in France, a multicentric, randomized trial comparing this experimental treatment vs control arm (same multimodal treatment without PDT) is planned.