Introduction:
Synchronous composite tumors are uncommon. Simultaneous, rather than metachronous or consecutive, occurrences of eosinophilic granuloma and Hodgkin's lymphoma in children are very rare. This is the first report of this kind in the medical literature.
Case presentation:
We report the case of a 12-year-old Iranian boy with eosinophilic granuloma localized in his leg around the knee and Hodgkin's lymphoma in a cervical lymph node. The two tumours occurred synchronously before the patient had received any treatment.
Conclusion:
Several cases of an association between eosinophilic granuloma and lymphoproliferative disorder have been reported. Some of these cases involve Hodgkin's lymphoma and Langerhans cell histiocytosis occurring in the same patient. Genetic or environmental etiologies have been postulated for eosinophilic granulomas which occur following Hodgkin's lymphomas, but have as yet not been proven. To our knowledge, synchronous occurrence of these two malignant processes in a patient who has not received any prior treatment is rare in children.