[Pseudotumoral soft tissue masses in children and adolescents]

Pseudotumoral soft tissue masses in children and adolescents are a frequent reason for consultation and a diagnostic dilemma. Soft tissue malignancies are relatively uncommon, unlike the large number of benign lesions that may be seen in the superficial tissue and that can be diagnosed with clinical characteristics.

This retrospective study concerns 161 children and adolescents less than 20 years old, referred for a soft tissue mass between 2007 and 2011. It describes their epidemiology, clinical characteristics, and course of care to validate a diagnostic strategy for such masses.

Final diagnoses were malignant tumors (44%), benign tumors (32%), and pseudotumoral lesions (24%). Clinical features were similar between these three groups except for age and tumor location, with more benign thoracic masses in younger children. Clinical and radiological association led to an accurate diagnosis for 50% of benign masses and with cytological analysis contribution in 79% of benign tumors and 86% of pseudotumoral lesions. Malignant tumors were suspected in only 39% of cases with radiological exams and in 89% after fine-needle aspiration, an essential additional diagnostic tool. Final diagnoses were formally established through simple standard clinical and radiological evaluation in 19 patients (11.8%; benign tumors, seven patients; malformations, eight patients; post-traumatic lesions, two patients; infection and inflammation, one patient each); ultrasound exam in five patients (3.1%; hemangioendotheliomas, two patients, fascial dehiscence, hemangioma, and vascular malformation, one patient each); MRI in four patients (2.5%; three vascular malformations and one lipoma); CT in two cases (1.2%; vascular malformation and myositis ossificans), and radiological examinations associated with cell aspiration in 15 cases (9.3%; ten benign tumors and five malignant tumors).

A multidisciplinary approach should be requested from oncological, radiological, and pathologic experts to optimize soft tissue mass management as soon as initial investigations start. The authors advise a diagnostic strategy for children with pseudotumoral soft tissue masses.