[Prophylactic radiotherapy in a single fraction of 10Gy at intervention pleural site in patient with malignant pleural mesothelioma: A retrospective monocentric cohort study].

PURPOSE: Prophylactic radiotherapy to prevent procedure-tracts metastases from malignant pleural mesothelioma remains controversial and clinical practice varies. The purpose was to assess the efficacy of local radiotherapy in a single fraction of 10Gy in preventing malignant seeding at intervention pleural site in patients with malignant pleural mesothelioma.

MATERIAL AND METHODS: This is a retrospective cohort study, including patients with histological confirmed malignant pleural mesothelioma treated by prophylactic irradiation to prevent interventional site metastases with a unique fraction of 10Gy with 6 to 18MeV, from January 1990 to December 2013 in the institut de cancérologie de Lorraine (Nancy, France).

RESULTS: Ninety-one patients were treated by irradiation in intervention site, involving 120 intervention pleural sites, 91 thoracoscopies, 17 thoracotomies with chest drain and 12 CT or ultrasound guided needle biopsies. The median follow-up was 7 months (interquartile between 3 and 15 months). The overall survival was 43.5% at 12 months. The local progression free survival was 43.7% at 12 month. The incidence of local recurrence was 8% at 12 months. The median interval from radiotherapy to local recurrence was 4 months (2; 32). No grade II or higher toxicity was observed.

CONCLUSION: Irradiation of pleural intervention sites with a single fraction of 10Gy is effective, well tolerated, simple, fast and cost effective.