Askin Tumor in Egyptian Patients; 5 Years Experience at the National Cancer Institute, Cairo University

Abstract

Background: Askin tumor is a primitive neuroectodermal tumor of the Ewing sarcoma family arising from soft tissues of the chest wall. It is the commonest chest wall malignancy in children and adolescents. Its diagnosis is complex and management requires a multidisciplinary work including chemotherapy for systemic disease and radiation therapy to assist local control which is achieved through surgery with or without reconstruction. Objective: To analyze report and understand the clinicopathological features, results and outcome of this tumor with assessment of early and late postoperative complications following resection and chest wall reconstruction. Materials and Methods: This is a retrospective analysis of 30 cases with chest wall ES/PNET presented to the National Cancer Institute; Cairo University between January 2011 and December 2015. All patients’ records were revised for age, sex, clinical presentation, imaging, pathology, operative notes, different treatment modalities given, early and late postoperative complications following surgical resection or reconstruction, and outcome including overall survival (OS) and disease free survival (DFS). Results: Our cohort included 30 patients with chest wall ES. The median follow up period (n = 30) was 33.7 months (ranging from 3.7 to 69.3 months). The median OS was 54.2 months with cumulative OS at 60 months which was 45.6%. The median DFS was 27.9 months with cumulative DFS at 60 months which was 40.6%. All cases were below 18 years with a male predominance (n = 19). The commonest affected sites were ribs (n = 22, 73.3%), the scapula (n = 5, 16.6%), the clavicle (n = 2, 6.66%) and the sternum (n = 1, 3.33%). 23 patients (76.6%) were presented with localized disease, and 7 patients (23.4%) were metastatic from the start. All patients received neoadjuvant chemotherapy (4 cycles of VAC/IE) followed by local control: either surgery (26 cases, 86.6%) or radical radiotherapy (3 cases, 10%). A single case of a rib ES with initial bilateral lung deposited where no local control was done. After chest wall resection, closure of the defect was done by 1 ry closure with no reconstruction or double layer prolene mesh and bone cement that was covered by pedicled flap (latissimus dorsi, serratus anterior or pectoralis major muscle flap). Postoperative radiation therapy was given to 9 patients: 4 (13.3%) had postoperative poor chemotherapy effect (<90% tumor necrosis), 3 (10%) had +ve microscopic safety margin and 2 (6.6%) had pleural based nodules with malignant pleural effusion at initial presentation. Conclusion: Askin’s tumor shows a dramatic response to polychemotherapy. Treatment of such tumor should include multidisciplinary working groups for optimum results and better survival.