P68 Surgery for mesothelioma: the case for macroscopic complete resection

Objective The role for radical surgery for Malignant Pleural Mesothelioma (MPM) remains controversial. There are advocates of less radical ‘debulking surgery’ who argue against the need for removal of diaphragm and pericardium because of increased morbidity. We test the hypothesis that survival is increased by the more radical operations intended to remove all visible tumour and achieve macroscopic complete resection (MCR). Methods Over a 13-year period, 362 patients underwent therapeutic surgery for MPM: in-group MCR: 232 (64%) patients underwent either extra-pleural pneumonectomy (135 patients (37%)) or radical pleurectomy-decortication (97 patients (27%)) with resection of diaphragm and pericardium. Whilst in group D: 130 (36%) underwent debulking surgery leaving macroscopic tumour in situ (55 patients (15%) by thoracotomy and 75 patients (21%) by VATS). The patients in the MCR group were younger (mean age 57.9 vs 66.1, p<0.0001) and more had epithelioid subtype (167 (72%) vs 86 (66.2%), p<0.0001). We compared the hospital outcomes and overall survival between these two groups. Results The mean length of stay was longer in group MCR than in group D (16.0 days vs 9.6 days, p<0.0001) but 30-day mortality was similar (12 (5.2%) vs 8 (6.2%), p=0.811). In univariate analysis, overall survival was significantly longer in the MCR group (mean survival 22 months vs 13 months, p<0.0001). A similar benefit was observed for the epithelioid pathological subgroup (mean survival 25.8 months vs 16.6 months, p<0.0001). Cox regression showed that surgery intended to achieve MCR was associated with a significantly reduced hazard of death after adjusting for age and pathological subtype (HR 0.72, 95% CI 0.55 to 0.93, p=0.014). Conclusions Surgery to increase survival in mesothelioma should be based on an intent to achieve macroscopic complete resection. This strategy should form the basis of future trials to evaluate the role of surgery in this disease.