Use this link to view the PDF file: LYTIC VS SCLEROTIC BONE LESIONS: DIAGNOSTIC ACCURACY OF CT-GUIDED CORE VS FNA BIOPSY TECHNIQUES
Purpose: CT-guided needle biopsy for primary or metastatic bone lesions is an accurate and less invasive approach than traditional open surgical biopsy. However, conflicting data exists in the literature concerning its diagnostic yield in both lytic and sclerotic lesions. In addition, no study has compared CORE to FNA diagnostic accuracy on the same lesion. The purpose of this study is to test the diagnostic yield of CORE versus FNA biopsy and relate it to lesion type, size, location and pathology.
Methods: CT-guided bone biopsies performed between January 2013 and June 2014 at our institution were included in the study. Only lytic or sclerotic lesions with concern for neoplasia were considered and those with osteomyelitis or soft tissue infection and mixed type were excluded. Fifty-one (51) females (mean age 61 years ±13.75, range 27-86) and 63 males (mean age 60.4 years ±13, range 19-82) were included in our population. Electronic medical records were reviewed and information on lesion type, location, size, types of needles used, diagnostic yield, primary tumor and pathological diagnosis were collected. Statistical analysis was carried out with SPSS through a chi-square test. A binary logistic regression model was created that predicted the relationship between the diagnostic yield and the combined effects of age, gender, final diagnosis, CORE or FNA used, and lesion size, type and location.
Results: Average lesion size was 23mm ±15, range 3-71mm. Overall diagnostic accuracy was 81.6%, with 79.4% for CORE and 43.4% for FNA. In cases where both FNA and CORE were done, CORE was diagnostic in 81.3% compared to FNA at 32.8%, p-value 0.045. None of the sclerotic lesions had a diagnostic FNA whereby CORE was 71.4% diagnostic. There was only one case in which FNA was diagnostic and CORE was not. The statistical model showed that only gender and final lesion pathology affect the diagnostic yield with p-values 0.049 and 0.018, respectively. CORE biopsy with neoplastic lesions is 85% diagnostic compared to benign lesions at 63.6%, p=0.025. For FNA, it is 90.5% versus 53.8% diagnostic (p=0.001), respectively.
Conclusion: When both are performed, diagnostic yield is higher with CORE compared to FNA, especially for sclerotic lesions. Diagnostic yield is also higher in the presence of neoplasia. We now recommend when immediate pathological review is unavailable a CORE biopsy be performed.