Ultrasonography of pediatric superficial soft tissue tumors and tumor-like lesions

Ultrasonography of pediatric superficial soft tissue tumors and tumor-like lesions

Reviewer: Madonna Burnett | ASA SIG: Paediatrics

Authors: Kim H, MD, Yoo S, Oh S, Jeon T, Kim J

Why the study was performed

This article was written to provide insight into the many different types of paediatric superficial soft tissue tumours and tumourlike lesions. Ultrasound is usually the first examination performed to look at these palpable or visible areas of concern in a paediatric patient. Along with clinical assessments such as age on presentation, clinical course, and any visible skin discolouration, ultrasound can provide detailed information about the lesion’s location and characterisation (solid vs cystic, vascularity, compressibility). Sufficient knowledge of the normal anatomy is also required. This article reviews the techniques used and what information can be discovered about superficial, soft tissue lesions in children.

What the paper looked at

It is necessary to clinically assess the lesion before scanning and ask for relevant clinical details such as when the lesion appeared, any size increase/decrease, and/ or discolouration or other symptoms.

Ultrasound technique was discussed. Superficial lesions should be examined with a high frequency linear transducer and parameters set appropriately. A gel standoff or excess ultrasound gel can be applied so as not to compress/distort the lesion. Echogenicity, compressibility and vascularity are all assessed. Spectral Doppler recorded for vessels with velocities and resistive index performed when necessary.

The article then discusses all the different types of superficial soft tissue tumour-like lesions and tumours.

What the study found

Superficial soft tissue lesions/tumours may be any of the following:

1. Vascular anomalies – these can be broken into vascular tumours and vascular malformations. Vascular tumours include infantile haemangioma, congenital haemangioma, tufted haemangioma and lobar capillary haemangioma. Vascular malformations are categorised histologically into lymphatic, capillary, venous, arteriovenous, or mixed malformations

2. Adipocytic tumours and other fatcontaining mass-like lesions – lipomas, lipoblastomas and subcutaneous fat necrosis

3. Fibroblastic and myofibroblastic lesions – such as nodular fasciitis, fibrous hamartoma, pericytic (perivascular) tumours such as infantile myofibroma and myofibromatosis

4. Neurogenic lesions – peripheral nerve sheath tumours, schwannomas, neurofibromas, malignant peripheral nerve sheath tumours and giant cell tumours of tendon sheath (fibrohistiocytic tumour)

5. Other benign lesions, such as ectodermal inclusion cysts, pilomatricoma, dermoid/epidermoid cysts and ganglia

6. Malignant soft tissue tumours –rhabdomyosarcoma, synovial sarcoma, infantile or congenital fibrosarcoma, subcutaneous panniculitis-like T-cell lymphoma. Multiple, subcutaneous nodules in neonates and infants should raise a concern for underlying malignancy. All the above-mentioned pathologies are discussed in detail with ultrasound and clinical findings.

Relevance to clinical practice

Ultrasound is frequently used as an initial workup of paediatric superficial soft tissue tumours and tumour-like lesions. Ultrasound can provide a specific diagnosis in certain pathologies and in others narrow the differential diagnosis. Lesions may need additional imaging or biopsy. Knowledge of ultrasound techniques and key imaging findings of these lesions in children will facilitate establishing the correct diagnosis and guiding management of the patient.

“Sufficient knowledge of the normal anatomy, proper ultrasonographic techniques, and the imaging findings of common and uncommon soft tissue lesions in children are crucial for accurate assessment and management of patients”