CERVICAL THYMUS ECTOPIA IN CHILDREN

Thymus ectopia is a rare solid neck lesion in children. The location of the formation along the path of thymus migration (thymopharyngeal duct), the echo pattern and the intensity of the MR signal, which is identical to the normally developed thymus, help in making a confident diagnosis. Materials and methods of the research: 14 pediatric patients were treated against the cervical thymus ectopia in 2018-2022 in the Russian Children's Clinical Hospital with the Pirogov Russian National Research Medical University of the Ministry of Healthcare of Russia and the National Scientific and Practical Center for Pediatric Hematology, Oncology and Immunology named after Dmitry Rogachev (both located in Moscow, Russia). The diagnosis was set only after the histological examination results in all cases. A differential diagnosis was made with other cystic and solid formations, taking into account its location and distribution according to ultrasound, computed tomography, and magnetic resonance imaging in each case. Results: stable, relapse-free treatment result was achieved after more than a year of follow-up in all cases. The correct diagnosis wasn’t set in every case until the biopsy results due to the rarity and diverse clinical and radiological picture of the disease. Conclusion: cervical thymus ectopia is a benign and relatively rare condition in children that is rarely diagnosed preoperatively by the visualization only. The conservative management may be appropriate in some cases when the thymus is in the chest cavity only, but surgical correction is more often needed in cases with the neck deforming formations.