# CT-guided bone biopsies with non-diagnostic results in pediatric patients—a multi-institutional 10-year retrospective review

## TL;DR

A study found that about one-third of CT-guided bone biopsies in children and teens are non-diagnostic, but most turn out to be benign, especially if the imaging shows non-aggressive features.

## Contribution

The study identifies factors associated with non-diagnostic CT-guided bone biopsies in pediatric patients and suggests a more conservative management approach for such cases.

## Key findings

- About one-third of CT-guided bone biopsies in pediatric patients yielded non-diagnostic results.
- Non-diagnostic results were strongly associated with lesions having non-aggressive radiological features.
- Most non-diagnostic lesions were ultimately confirmed to be benign.

## Abstract

This study aimed to determine the diagnostic yield of CT-guided bone biopsies in pediatric patients, the outcome of non-diagnostic CT biopsy results, and to establish factors associated with non-diagnostic biopsy results.

This is a retrospective study of consecutive pediatric patients ≤ 21 years who underwent CT-guided bone biopsies in three tertiary referral hospitals from December 2011 to March 2022. Clinical information, pre-biopsy CT and MRI images, procedural details, pathological results, and follow-up were assessed. Fisher’s exact test was used to compare categorical variables. Mann–Whitney U-test and unpaired t-test were used to compare non-parametric and parametric variables, respectively. Statistical significance was set a p < 0.05.

A total of 138 patients (mean age 13.9 ± 4.5 years; 95 (60%) male patients) with 157 CT-guided bone biopsies were studied, which yielded 38.2% (60/157) non-diagnostic, 23.6% (37/157) benign, and 38.2% (60/157) malignant results. Most non-diagnostic lesions (88.3% [53/60]) were subsequently determined to be benign. Factors associated with non-diagnostic biopsy results were cystic lesions (p = 0.003) incidental lesions (p = 0.03), fewer (p = 0.02) and shorter (p = 0.01) tissue cores, non-aggressive radiological features, including narrow zone of transition (p < 0.001), sclerotic margin (p < 0.001), no cortical destruction (p < 0.001), no periosteal reaction (p < 0.001), or no extra-osseous soft tissue mass (p < 0.001).

About one-third of CT-guided bone biopsies in pediatric patients yielded non-diagnostic results, though most were ultimately confirmed to be benign. In children and adolescents with suspected primary bone tumors, CT-guided bone biopsy with non-diagnostic histopathological results strongly favors benignity in lesions with non-aggressive imaging features and should align management towards a more conservative approach.

Question
Limited data exist on the prevalence and outcome of non-diagnostic CT-guided bone biopsy in pediatric patients to guide clinical management.

Findings
About one-third of CT-guided bone biopsies in pediatric patients were non-diagnostic, though most were ultimately benign. Lesions with non-aggressive features were associated with non-diagnostic results.

Clinical relevance
In the setting of multidisciplinary care for patients with suspected primary bone tumors, non-diagnostic CT-guided bone biopsy—particularly in lesions with non-aggressive imaging features—strongly favors benignity, which should steer management towards a more conservative approach.