Objective To detect the effectiveness and accuracy of fine-needle biopsy (FNB) as an accurate technique for the diagnosis of lymphoma in children.

Methods 23 patients underwent a FNB procedure. The patients ranged in age from 2 to 16 years, with a mean age of 9 years. For the whole series, two patients (8.7%) had tumours in the anterior mediastinum, 18 had tumours (78.26%) in the middle mediastinum and three in the posterior mediastinum (13%). All masses were punctured with a 18 gauge FNB needle.

Results Lymphomas were the most common tumours and represented 73.9% of our patients (17/23). They generally presented in the teen years and were located in the middle mediastinum. Lymphomas were Hodgkins disease in 39% and non-Hodgkins lymphoma in the remaining 61%. Neurogenic tumours represented 13% of our total group and were the second most common mediastinal tumour. They were located in the posterior mediastinum. There were two cystic lesions of the mediastinum, representing 8.7% of the patient population, including cystic hygroma and pericardial cysts. Adequate diagnostic cytological material was obtained in 95.5% of cases.

Conclusion Computed tomography image-guided percutaneous FNB of the mediastinum is a diagnostically helpful, effective, secure, minimally invasive procedure that can be performed in children as part of the evaluation of a mediastinal mass lesion and diagnosis of lymphoma.