Inguinal hernia in patients with Ewing sarcoma: A clue to etiology

Background. Various congenital anomalies have been associated with childhoo d cancer, but as yet no anomaly has been consistently found with Ewing sarc oma (ES). Recently a large case-control study of ES patients reported a gre ater number of hernias in both cases and their sibling controls than in pop ulation controls. Most of these hernias were inguinal. Because these anomal ies were also reported previously in two case series, we looked for inguina l hernias in a different population of ES patients. Procedure. We abstracte d medical records for 306 pathologically confirmed ES/primitive neuroectode rmal tumor (PNET) patients seen at NIH between 1960 and 1992. Epidemiologic al data on demographics and medical conditions were analyzed. The frequency of anomalies was compared to expected rates to calculate relative risk and confidence intervals. Results. Anomalies were present in 67 (22%) cases. A particular anomaly, inguinal hernia, was reported for 13 (5%) NIH cases. C ompared to population estimates for white children, the relative risk of in guinal hernia among white NIH cases was 13.3 (95% CI 3.60-34.1) for females and 6.67 (95% Cl 2.67-13.7) for males. Conclusions. The findings of inguin al hernias in some patients with ES suggest that a disruption in normal emb ryological development occurred. This may provide an important clue to the etiology of ES. We hypothesize that these hernias may relate to an in utero exposure or indicate an underlying genetic disorder. Future studies should carefully evaluate ES families for genetic disease and explore environment al factors. Med. Pediatr. Oncol. 34:195-199, 2000. Published 2000 Wiley-Lis s, Inc.