P491 A rare pleural based malignancy in childhood

Introduction Malignant Mesothelioma (MM) is a rare invasive neoplasm arising from the mesothelial lining of several organs, primarily the pleura and peritoneum1. A causal relationship with asbestos exposure is well established, however; MM can occur in the absence of well-defined risk factors and at an earlier age2. Case Presentation A 15 year old boy, presented to the Emergency Department with a 6-week history of cough, 5 kilogram weight loss and right sided pleuritic chest pain. He had attended the ED 4 weeks prior to this with chest pain, cough, temperature and a chest infection was diagnosed. Repeat chest x-raydemonstrated a right lower lobe consolidation with obscuration of the hemidiaphragm and a suspected pleural based opacification. Laboratory investigations showed a hypochromic microcytic anaemia, hyponatremia and raised inflammatory markers. A CT of thorax, abdomen and pelvis showed lobulated rind of pleural based soft tissue densities in the right thorax with downward invasion through the hemidiaphragm into the liver. On transfer to a tertiary Paediatric Oncology centre, A CT-guided biopsy demonstrated a malignant epithelioid neoplasm confirming a diagnosis of malignant mesothelioma with EWSR-ATF1 rearrangement. He was treated with 2 cycles of Pemetrexed and Cisplatin Chemotherapy (NCCP guideline). Follow up imaging demonstrated disease progression which coincided with clinical deterioration. NG feeding, PleuralX drain and Oxygen therapy are part of his treatment regimen. Vinorelbine monotherapy was commenced and a Palliative approach has been adopted. Currently he is stable awaiting further imaging. Discussion MM is rare is young people. The genetic susceptibility to MM is complex and recently an EWSR1-ATF1 fusion transcript has been described in 4 younger patients without prior asbestos exposure2. The prognosis in MM is poor but improved survival in younger patients has been observed1. We wish to highlight this case because it is rarely encountered in a paediatric setting.