Large-Bore Vacuum Suction Biopsy of Pediatric Soft Tissue Tumors: A 5-Year Retrospective Analysis of Safety and Effectiveness.

Introduction: Percutaneous large-bore vacuum suction biopsy (LBVSB) is an innovative alternative to open surgical biopsy and minimally invasive image-guided percutaneous core needle biopsy (PCNB) for pediatric soft tissue tumors. This study reviews our experience using this modality.

Methods: A retrospective review of all children undergoing LBVSB between 2019 and 2025 was performed. Operative notes, pathology reports, and clinical follow-ups were analyzed to determine tissue adequacy and diagnosis/prognosis.

Results: Fifty-five children underwent a total of 59 ultrasound-guided LBVSBs. The average age of patients was 10.5 years, but ranged from 4 months to 20 years. Biopsy was performed most often with a 10 g needle (56% of cases). The median number of samples was six (interquartile range [IQR]: 4-8), and individual core sizes ranged from 0.2 to 2.7 cm, with a median diameter of 0.3 cm (IQR: 0.2-0.4). Pathologic evaluation of the biopsy specimens accurately confirmed the final diagnosis in 54/55 cases (98% accuracy). Repeat surgical biopsy was necessary for two patients, one to more accurately characterize the tumor (Hodgkin lymphoma), and another due to persistent nodal swelling following a diagnostic biopsy (lymphoid tissue with fibrosis). Tissue samples were adequate for obtaining immunohistochemistry and molecular fusion transcripts in all cases where these were deemed necessary to make the final diagnosis. The median procedure time was 24 min (IQR: 20-30.5 min). There were two hemorrhagic complications directly associated with the biopsy procedures, and one complication associated with general anesthesia administration.

Conclusion: Our experience demonstrates that image-guided percutaneous LBVSB is an accurate and efficient way to biopsy pediatric soft tissue tumors and seems to be quite safe based on our small cohort. LBVSB samples were adequate in all our patients, allowing for immunohistochemistry and fusion analysis when necessary. There were only two complications directly related to the procedure, and a repeat biopsy was only required in two cases. LBVSB can be considered as an initial diagnostic tool for certain pediatric soft tissue tumors.