Mediastinal tumors - Pediatric Surgery

Mediastinal tumors - Pediatric Surgery Mediastinal Tumors . Neurogenic Tumors of the Mediastinum .   click the images for more details       Incidence . Illustrations In the leading symptom 'mediastinal tumors' the neurogenic tumors in children belong to the most frequent ones besides the inflammatory and neoplastic lymphomas; they account for 1/3 of all space-occupying lesions of the mediastinum. show details Clinical significance . Illustration 1. In case of unspecific and general symptoms and an appropriate age (2 to 3 years) a neuroblastoma has to be excluded by screening for urinary catecholamine catabolites; and, if pathological values are found, the specific sites of neuroblastomas must be checked including the mediastinum. 2. In case of a visible and/or palpable mass in the neck or the abdomen it is necessary to consider a tumor located primarily in the mediastinum, or a metastatic neurogenic one. 3. In case of a mass accidentally discovered on an x-ray in two planes, located in the posterior mediastinum in toddlers and schoolchildren, a benign ganglioneuroma is very likely. show details Etiology .   The neurogenic tumors of the posterior mediastinum derive from the later grenz ray.   Pathology, anatomical types .   The neurogenic tumors are derived from the grenz ray, and, depending on the degree of differentiation, malignant neuroblastomas, semimalignant ganglioneuroblastomas and benign ganglioneuroma occur. In addition, neurofibromas as descendants of the peripheral nerves occur. In childhood, many so-called mediastinal tumors consist of masses and cysts of developmental origin.   Clinical presentation (history, findings, clinical skills) . Illustrations The clinical picture depends on: a) the degree of differentiation and/or of malignancy of the tumor; b) the age at clinical presentation; c) the possible expansion into the neck, abdomen and spinal channel. 15 % of all neuroblastomas are localized mainly within the thorax and cause unspecific general symptoms, and in some of them, respiratory, or, infrequently, neurological symptoms may be observed (for instance paraplegia in the newborn). An expansion into the neck or the abdomen does not only occur in neuroblastoma and in infants, but in more mature neurogenic tumors and older children, too. The ganglioneuroma is either found on an x-ray of the chest performed for other reasons, or it causes on the same side a Horner's syndrome and/or pain in the back, shoulder or arm. show details Natural history .   Non-treatment of a neuroblastoma leads to death, and in case of a ganglioneuroma to progressively space-occupying growth between the structures (for instance cervicobrachial plexus), making a total excision very difficult.   Differential diagnosis . Illustrations The differential diagnosis includes in decreasing order lymphomas, teratomas or dermoid cysts, entero- and bronchogenic cysts and lesions of the thymus; and in case of the posterior mediastinum mainly tumors of the peripheral nerves, and enterogenic cysts. show details Work-up examinations . Illustrations Additional examinations are: 1. X-ray of the chest in two planes. 2. Esophagogram, esophagoscopy, echocardiogram. 3. CT and/or MRI without/with contrast application (replacing esophagogram). 4. In case of neurogenic tumors: quantification of the different catecholamine catabolites, and in case of neuroblastoma examinations for staging, local expansion and biological characterization. show details Therapy . Illustrations In case of neuroblastoma, usually a multidisciplinary treatment is performed. Initial surgery is mainly for biopsy and secondary surgery for excision of a residual tumor and further histological examinations. All other neurogenic tumors as well as most mediastinal tumors should be excised totally either by thoracotomy oder by thoracoscopy and followed by a histological work-up (for instance search for ganglioneuroblastoma in a ganglioneuroma). In contrast to the plexiform neurofibroma which lies within the cervicobrachial plexus and can hardly be excised totally, the neurofibroma of the other sites (posterior mediastinum, along the thoracic cage) should be excised radically. All tumors with an intraspinal expansion call for a primary laminectomy. show details Prognosis .   Total recovery in ganglioneuroma except for a pre-existing or an unavoidable surgical Horner's syndrome. In case of expansion into the neck or abdomen, the prognosis depends on the possibility of a total excision. In case of neuroblastoma, the prognosis additionally depends on the age of the child, and the stage and biology of the tumor.