PRIMARY MEDIASTINAL MASSES - A COMPARISON OF ADULT AND PEDIATRIC POPULATIONS

Since 1944 62 pediatric patients with primary cysts and tumors of the mediastinum have been operated on at our institution. We compared this group with 195 adult patients with similar diagnoses who were operate d on during this period. Comparisons were made with regard to histolog ic type, location, presenting symptoms, physical findings, and surgica l complications. We found significant increases in the prevalence of l ymphoma in adults (41/195 versus 4/62, p < 0.05) and of neurogenic tum ors in children (21/62 versus 24/195, p < 0.05). There were no signifi cant differences in the prevalence of thymic tumors (51/195 versus 22/ 62), germ cell tumors (24/195 versus 4/62), and cysts (32/195 versus 1 5/62). There was no difference in the prevalence of symptomatic patien ts (99/195 versus 36/62). The prevalence of malignancy has increased i n both groups since 1970 (2/28 versus 16/34 in children, p < 0.01; and 14/56 versus 69/139 in adults, p < 0.05). This is attributed to a ris e in the prevalence of malignant neurogenic tumors in children and to an increase in the prevalence of lymphomas in adults. Tumor size, loca tion, and the presence of symptoms were predictive of malignancy in th e adult population but not in the pediatric population. No difference existed in mortality and morbidity between the two groups. All three p ediatric deaths were directly related to loss of airway control as a r esult of mass effect from the tumor. Definite differences exist betwee n the adult and pediatric populations with regard to mediastinal tumor s. These differences need to be considered carefully when evaluating a nd planning treatment for a child with a mediastinal mass.