title: The evolution of clonality testing in the diagnosis and monitoring of hematological malignancies.
abstract: Currently, distinguishing between benign and malignant lymphoid proliferations is based on a combination of clinical characteristics, cyto/histomorphology, immunophenotype and the identification of well-defined chromosomal aberrations. However, such diagnoses remain challenging in 10-15% of cases of lymphoproliferative disorders, and clonality assessments are often required to confirm diagnostic suspicions. In recent years, the development of new techniques for clonality detection has allowed researchers to better characterize, classify and monitor hematological neoplasms. In the past, clonality was primarily studied by performing Southern blotting analyses to characterize rearrangements in segments of the IG and TCR genes. Currently, the most commonly used method in the clinical molecular diagnostic laboratory is polymerase chain reaction (PCR), which is an extremely sensitive technique for detecting nucleic acids. This technique is rapid, accurate, specific, and sensitive, and it can be used to analyze small biopsies as well as formalin-fixed paraffin-embedded samples. These advantages make PCR-based approaches the current gold standard for IG/TCR clonality testing. Since the completion of the first human genome sequence, there has been a rapid development of technologies to facilitate high-throughput sequencing of DNA. These techniques have been applied to the deep characterization and classification of various diseases, patient stratification, and the monitoring of minimal residual disease. Furthermore, these novel approaches have the potential to significantly improve the sensitivity and cost of clonality assays and post-treatment monitoring of B- and T-cell malignancies. However, more studies will be required to demonstrate the utility, sensitivity, and benefits of these methods in order to warrant their adoption into clinical practice. In this review, recent developments in clonality testing are examined with an emphasis on highly sensitive systems for improving diagnostic workups and minimal residual disease assessments.
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Gazzola
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Mannu
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Maura
authors.initials: M
authors.lastname: Rossi
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Maria Antonella
authors.initials: MA
authors.lastname: Laginestra
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Sapienza
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Fuligni
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Maryam
authors.initials: M
authors.lastname: Etebari
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Melle
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Sabattini
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Agostinelli
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Bacci
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Sagramoso Sacchetti
authors.affiliation: Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Bologna, Italy.
authors.forename: Stefano Aldo
authors.initials: SA
authors.lastname: Pileri
authors.affiliation: Molecular Pathology Laboratory, Department of Experimental, Diagnostic, and Specialty Medicine, Bologna University Medical School, Unit of Hematopathology, S. Orsola Malpighi Hospital, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Piccaluga
keywords: PCR; clonality; hematological neoplasms; high-throughput sequencing