Albumin Enhanced Morphometric Image Analysis CLL

Abstract

Background: The heterogeneity of lymphocytes from patients with chronic lymphocytic leukemia (CLL) and blood film artifacts make morphologic subclassification of this disease difficult. Methods: We reviewed paired blood films prepared from ethylene-diamine-tetraacetic acid (ETDA) samples with and without bovine serum albumin (BSA) from 82 CLL patients. Group 1 adhered to NCCLS specifications for the preparations of EDTA blood films. Group 2 consisted of blood films containing EDTA and a 1:12 dilution of 22% BSA. Eight patients were selected for digital photomicroscopy and statistical analysis. Approximately 100 lymphocytes from each slide were digitally captured. Results: The mean cell area ± standard error was 127.8 μm2 ± 1.42 for (n = 793) for group 1 versus 100.7 μm2 ± 1.39 (n = 831) for group 2. The nuclear area was 88.9 μm2 ± 0.85 for group 1 versus 76.4 μm2 ± 0.83 for group 2. For the nuclear transmittance, the values were 97.6 ± 0.85 for group 1 and 104.1 ± 0.83 for group 2. The nuclear:cytoplasmic ratios were 0.71 ± 0.003 for group 1 and 0.78 ± 0.003 for group 2. All differences were statistically significant (P < 0.001). Conclusions: BSA addition results in the reduction of atypical lymphocytes and a decrease in smudge cells. BSA also decreases the lymphocyte area and nuclear area, whereas nuclear transmittance and nuclear:cytoplasmic ratio are increased. A standardized method of slide preparation would allow accurate interlaboratory comparison. The use of BSA may permit better implementation of the blood film-based subclassification of CLL and lead to a better correlation of morphology with cytogenetics and immunophenotyping.