Polymerase Chain Reaction-Based Clonality Analysis of Cutaneous B-Cell Lymphoproliferative Processes

Abstract

INTRODUCTION:The differential diagnosis of B-cell lymphoproliferative processes remains a challenge for pathologists, dermatologists and oncologists, despite advances in histology, immunohistochemistry and molecular biology.OBJECTIVE:Evaluate aid and limitations of clonality analysis in the diagnosis of primary cutaneous B-cell lymphomas and B-cell pseudolymphomas.METHODS:This study included 29 cases of B-cell lymphoproliferative processes classified as primary cutaneous B-cell lymphomas (13), B-cell pseudolymphomas (6) and inconclusive cases (10) using histology and immunohistochemistry. The clonality analysis was performed by polymerase chain reaction analysis of immunoglobulin light chain and heavy chain rearrangements.RESULTS:DNA quality was shown to be generally poor; eight samples were inadequate for polymerase chain reaction analysis. The results showed monoclonality in eight of the primary cutaneous B-cell lymphomas and polyclonality in four of the B-cell pseudolymphomas. In addition, monoclonality was shown in two of the inconclusive cases by histology and immunohistochemistry, demonstrating the utility of polymerase chain reaction as an ancillary diagnostic tool for primary cutaneous B-cell lymphomas.DISCUSSION:The low quality DNA extracted from these cases demanded the use of an IgH protocol that yielded small fragments and IgK. Both methods used together improved detection.CONCLUSION:Use of the two protocols, immunoglobulin heavy chain FR3-trad and immunoglobulin light chain-Kappa Biomed protocols for clonality analysis improved diagnostic accuracy.

Monoclonality of multifocal epithelioid hemangioendothelioma of the liver by analysis of WWTR1-CAMTA1 breakpoints

“…Among tumors characterized by recurrent chromosomal translocations, gene rearrangement is the most likely initiating event of tumorigenesis and the resulting fusion product represents the definitive idiotypic clonal marker (8, 9). There are only a few clonality studies comparing the rearrangement breakpoints, most of them investigating multifocal lymphoproliferative processes, where PCR analysis of clonality was used as an important diagnostic tool (9–13).…”

PCR Analysis of IgH and TCR-γ Gene Rearrangements as a Confirmatory Diagnostic Tool for Lymphoproliferative Disorders

“…However, the advantage of molecular studies as complementary diagnostic techniques in various lymphoproliferative disorders has been discussed previously [25][26][27][28][29][30]. The use of such techniques for definite diagnosis in inconclusive cases of immunomorphological studies is arguable, and has been investigated just in some case-series studies.…”

Benign lymphoid hyperplasia (pseudolymphoma) of soft tissue

“…A clinicopathologic study of 14 cases of pulmonary nodular lymphoid hyperplasia by the Armed Forces Institute of Pathology in 2000 failed to reveal immunoglobulin heavy chain rearrangement or translocation between chromosomes 14 and 18 (t(14;18)), suggesting that, although uncommon, nodular lymphoid hyperplasia of the lung is a true reactive lesion [16]. Likewise, Melotti et al [17] evaluated 29 cases of cutaneous B-cell lymphoproliferative processes. Although the study was hampered by poor nucleic acid recovery, polyclonality was demonstrated in all cutaneous pseudolymphomas with analyzable DNA.…”