Large Neck and Chest Mass in a Newborn

Abstract

Large right-sided neck and chest mass in a newborn.A term male newborn is transferred to neonatal intensive care unit a few hours after birth because of a huge cervicothoracic mass.There is no history of consanguinity between the parents, and another child is healthy.Diffuse proliferation of rounded cells with prominent eccentric nuclei and hyalinelike inclusion bodies in the cytoplasm. Immunoreactive for vimentin, cytokeratin, and epithelial membrane antigen.Huge cervicothoracic mass in newborn:Malignant Rhabdoid Tumor (MRT)MRT is very rare in the neonatal period. This highly aggressive tumor of controversial origin initially was described in the kidney by Beckwith and Palmer in 1978 as a sarcomatous variant of Wilms tumor1,2. MRT is fatal during the neonatal period2. Only five cases of extrarenal MRT have been reported during the neonatal period1,3,4. The tumor predominantly involves deep axial locations such as the neck or paraspinal region.Review of a relatively large series of three independent studies of extrarenal MRT, consisting of 49 patients, revealed the following data: 25 females (51%) and 24 males (49%), with age ranges from 2 months to 56 years and a median age of 7.3 years5. Most cases were infants or children, and 28 patients (57%) were younger than 10 years of age. The tumors arose most frequently in deep, axial locations, including the neck and paravertebral regions. The detailed anatomic distribution of primary tumors was as follows: neck (12.2%), thigh (12.2%), abdominal cavity and retroperitoneum (10.2%), paraspinal region (8.2%), pelvic cavity (8.2%), chest wall (6.1%), and perineal region (4.1%).MRTs have rapidly fatal clinical courses in most cases. The 5-year survival rate in the previously noted series was less than 20%; about 42% of patients died within 1 year of diagnosis.A unique type of MRT is seen in soft tissue, in which the initial presentation is widely disseminated disease at birth or shortly thereafter and no demonstrable primary tumor in the kidney or brain. Known as “congenital disseminated malignant rhabdoid tumor,”5 these tumors sometimes have placental metastases and are associated with a rapidly deteriorating clinical course terminating in death.Microscopically, MRT is composed of a diffuse proliferation of rounded or polygonal cells that have eccentric nuclei, prominent nucleoli, and glass eosinophilic cytoplasm containing hyalinelike inclusion bodies, arranged in sheets and nests. Such characteristic “rhabdoid cells” also are present in certain soft-tissue sarcomas such as synovial sarcoma and leiomyosarcoma. Both MRT of soft tissues and proximal type epithelioid sarcoma show immunoreactivity for vimentin, cytokeratin, and epithelial membrane antigen5.JoDee M. Anderson, MD, Division of Neonatal Medicine, Oregon Health & Science University, Portland, OR.