Spectral characteristics of acute lymphoblastic leukemia in childhood.

Although the differentiation and classification of acute leukemia are based upon cytochemical features as well as immunologic, cytogenetic, and molecular characteristics, in many cases the morphological distinction of normal lymphocytes from lymphoblasts of acute lymphoblastic leukemia (ALL) is difficult using light microscopy. In this study the distinction between normal lymphocytes and lymphoblasts of childhood ALL is proposed using their spectral characteristics. The method has been based upon the analysis and classification of optical absorption characteristics of the bone marrow cells. Spectral microscopy system is capable of capturing a great number of narrow-band images, in the wide spectral range of the optical spectrum. The analysis showed statistically significant difference (P < 0.0001) between normal lymphocytes and lymphoblasts as far as it concerns the detection, identification and mapping of their spectral absorption characteristics. Our results suggest the potential of spectral imaging as a new method for the distinction of lymphocytes from lymphoblasts in cases that with the light microscope, the morphologic differences are not visible in the bone marrow smears at diagnosis or the follow up of the children with ALL.