Cytogenetic and FISH studies in myelodysplasia, acute myeloid leukemia, chronic lymphocytic leukemia and lymphoma

Abstract

Conventional cytogenetic studies are widely used today to diagnose and manage patients with hematological malignancies. The application of fluorescence in situ hybridization (FISH) with chromosome-specific DNA probes helps to further define molecular subclasses and cytogenetic risk categories for patients with these disorders. Moreover, FISH permits analysis of proliferating (metaphase cells) and non-proliferating (interphase nuclei) cells, and is useful in establishing the percentage of neoplastic cells before and after therapy (minimal residual disease). For patients with myelodysplasia or acute myeloid leukemia, these chromosome techniques are important for accurate diagnosis and classification of disease and to help decide treatment and monitor response to therapy. Conventional cytogenetic studies have been problematic in chronic lymphocytic leukemia because the neoplastic cells divide infrequently. However, interphase FISH studies now permit detection of chromosome anomalies with prognostic significance in chronic lymphocytic leukemia. The World Health Organization recognizes that genetic anomalies are one of the most reliable criteria for classification of malignant lymphomas. New methods to extract individual nuclei from paraffin-embedded tissue are now available which permit the use of interphase FISH to detect important chromosome anomalies in lymphoma.

Spectral model for diagnosis of acute leukemias in whole blood and plasma through Raman spectroscopy

“…107002-7 October 2018 • Vol. 23 (10) group, and a positive peak at 1375 cm −1 attributed to glucosamine, which presents in a low concentration in the healthy group compared to the leukemic group. Regarding the carotenoid peaks in plasma, the exploratory analysis by PCA showed that both PC2 and PC4 presented peaks of this component (1004, 1159/1160, and 1520∕1525 cm −1 ), 24,30 and SC2 and SC4 indicated significant differences, indicating the presence of these components in high concentrations in the healthy group, as demonstrated by González-Solís et al, 24 when analyzing Raman spectra of blood in leukemic subjects.…”

“…38,39 However, the PLS-DA stands out from the PCA-DA because, in addition to the information of the differences between the groups, the variances obtained within each group are also recognized, and these variances are associated to the groups when modeling the regression curve; [38][39][40] therefore, the PLS-DA leads to better performance in the classification of samples when compared to PCA-DA. 38,39 Compared to the techniques currently available for the diagnosis of acute leukemias based on cytomorphology and immunophenotyping, [9][10][11]13,14 RS model presented accuracy (97.1%) close to phenotyping (94% 13 ) and sensitivity and specificity (95.7% and 98.0%) close or overmatch the flow cytometry technique (97% and 88% 14 ), despite the difficulty in obtaining the sensitivity and specificity reference values for the standard diagnostic techniques of myelogram and phenotyping. Thus, Raman-based analysis could significantly differentiate between healthy and leukemic individuals based on differences in the spectral pattern related to the chemical composition (amino acids and carotenoids) of the blood plasma, and cellularity (red and white cells) and chemical composition (proteins) in the whole blood using a small volume of peripheral blood.…”

“…107002-9 October 2018 • Vol. 23 (10) whole blood revealed that the PC loadings 2 and 3 presented peaks attributed to proteins, amino acids, and carbohydrates, showing higher intensity in the healthy group, while in the leukemic group, particularly the loading 3, presented higher intensity of phospholipids constituents of the cell's membrane due to the characteristic hypercellularity of acute leukemias. In plasma, PCA identified major differences in PC loadings 2 and 4, where the healthy group showed peaks that indicate higher amount of proteins, amino acids, free phospholipids, and carotenoids compared to the leukemic group.…”

“…The cytogenetics and fluorescence in situ hybridization are aimed to identify specific genes and chromosomal alterations (deletions, translocations, and cryptic rearrangements) implicated in the process of leukemogenesis. 10 Immunophenotyping by flow cytometry and molecular biology are also part of the range of exams currently available for the elaboration of a definitive diagnosis. 11 Only after confirmation will the leukemia therapy be started and the prognosis known, but the average time to release the results of these tests varies from 3 to 5 days, impacting negatively the development and control of the disease.…”

Bone marrow aspirate and biopsy: a pathologist's perspective. II. interpretation of the bone marrow aspirate and biopsy

“…In the future, these discoveries may lead to targeted chemotherapy, such as the use of tyrosine kinase inhibitors to target the ectopic expression of receptor tyrosine kinase fibroblast growth factor receptor 3 associated with the t(4;14) translocation (335). Since FISH is a very sensitive technique for the detection of chromosome abnormalities, it is widely used both for diagnosis and for follow-up of MRD post chemotherapy and bone marrow transplant (336)(337)(338)(339).…”