Comparison of Adequacy and Diagnostic Utility of FNA and Tissue Core Biopsy Samples Submitted for Flow Cytometric Analysis
George D Smith, Jonathan D Boyd, Heng Hong, Ridas Juskevicius. East Carolina University, Greenville, NC
Background: Flow cytometric (FC) analysis is a commonly performed study, often essential for diagnosis of hematologic neoplasms. FC requires a sufficient quantity of viable cells for accurate characterization of a neoplasm's phenotype. Two methods for obtaining samples from tissues for FC include fine needle aspiration (FNA) and needle core biopsy (NCB). To our knowledge, there are no large studies comparing the utility of these two sampling methods for FC.
Design: Our files from 01/01/2003 to 06/01/2012 were searched for FC cases that were sampled via FNA or NCB. Cases sampled by other methods (e.g. excisional biopsy) were not collected. Data fields were collected from each patient file and compiled into a separate database. Cases with incomplete data and non-hematologic neoplasms were excluded. Statistical analysis was performed using SPSS (v17.0).
Results: 571 cases were reviewed. Of these, 72 had a final pathologic diagnosis of non-hematologic neoplasm, and 43 had one or more incomplete data fields, leaving 456 total cases for analysis. 116 of these cases were sampled by NCB and 340 were sampled by FNA. Using the study data, the total viable cells (TVC) collected in each case was calculated. The calculated TVC was then converted to logarithmic scale as "Log TVC." The total Log TVC data for the entire study set is normally distributed. Descriptive statistics comparing the FNA and NCB subgroups were calculated, and the mean of Log TVC for the FNA subgroup (6.09) was significantly higher than NCB (5.88). When the cellularity of the sample (in Log TVC) increases, the likelihood of achieving a valid interpretation of the flow cytometric analysis also increases (Figure 1). Comparing FNA to NCB demonstrated FNA to be superior in specimen viability(p=0.000234), log TVC (p=0.00211) and the percent of cases with a final FC interpretation (p=0.011).
Conclusions: FNA was found to be significantly better than NCB for obtaining material for FC. How best to use these findings remains unclear. FNA provides a superior specimen for FC, but NCB resulted in fewer indeterminate final diagnoses, as expected due to the benefit of histologic correlation. In our opinion, NCB for histology combined with FNA for FC may yield the best results for the diagnosis of hematologic neoplasms.
Wednesday, March 6, 2013 1:00 PM
Poster Session VI # 212, Wednesday Afternoon