Pleuropulmonary bastoma in children: an unusual presentation mimicking pneumonia

Abstract

Background: Pleuropulmonary blastoma (PPB) is a rare but aggressive tumor in children. We report the case of a 3 year-old boy who presented cough and intermittent fever for one month. After multiple antibiotics courses, he presented a mild hemoptysis and dyspnea with anemia and biological inflammatory syndrome but no change in general condition. Chest X-Ray showed a left parenchymal opacity extending to the entire left lung with mediastinal deviation to the right. Ultrasonography didn’t show pleural effusion. We investigated the nature of the lesion. Methods: CT scan showed a voluminous heterogeneous intrathoracic mass with complete left lower lobe retraction, along with two right pulmonary nodules. A transcutaneous needle biopsy of this mass showed a non-specific inflammatory tissue with no tumor cells. Bronchoscopy revealed an obstructing endobronchial mass of the left lower lobar bronchus, which was biopsied. Results: Histological examination showed features of embryonal rhabdomyosarcoma (RMS) with muscular markers expression. Diagnosis hypotheses favor PPB with bronchial extension rather than primitive bronchial RMS. No distant metastases were identified and chemotherapy was introduced including Ifosfamide, Vincristine and Actinomycin. Meanwhile, genetic analysis showed DICER1 mutation. Discussion and conclusion: PPB is a rare and aggressive malignant tumor in children, usually part of DICER1 predisposition syndrome. Diagnosis may be challenging because of atypical presentations. PPB requires a prompt diagnosis and a multidisciplinary approach including genetic counseling. Prognosis is closely related to the size of the tumor and metastatic status at time of diagnosis.