Format

Send to

Choose Destination
J Clin Pathol. 2018 Mar;71(3):215-220. doi: 10.1136/jclinpath-2017-204548. Epub 2017 Aug 3.

Comparison of protein-based cell-of-origin classification to the Lymph2Cx RNA assay in a cohort of diffuse large B-cell lymphomas in Malaysia.

Author information

1
Department of Pathology, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
2
Division of Hematology and Transfusion Medicine, Department of Pathology and Laboratory Medicine, University of Calgary/Calgary Laboratory Services (CLS), Calgary, Canada.

Abstract

AIMS:

The cell of origin (COO) based molecular characterisation into germinal centre B-cell-like (GCB) and activated B-cell-like (ABC) subtypes are central to the pathogenesis and clinical course in diffuse large B-cell lymphoma (DLBCL). Globally, clinical laboratories employ pragmatic but less than ideal immunohistochemical (IHC) assay for COO classification. Novel RNA-based platforms using routine pathology samples are emerging as new gold standard and offer unique opportunities for assay standardisation for laboratories across the world. We evaluated our IHC protocols against RNA-based technologies to determine concordance; additionally, we gauged the impact of preanalytical variation on the performance of Lymph2Cx assay.

METHODS:

Diagnostic biopsies (n=104) were examined for COO classification, employing automated RNA digital quantification assay (Lymph2Cx). Results were equated against IHC-based COO categorisation. Assay performance was assessed through its impact on overall survival (OS).

RESULTS:

96 (92%) informative samples were labelled as GCB (38/96; 40%) and non-GCB (58/96; 60%) by IHC evaluation. Lymph2Cx catalogued 36/96 (37%) samples as GCB, 45/96 (47%) as ABC and 15/96 (16%) as unclassified. Lymph2Cx being reference, IHC protocol revealed sensitivity of 81% for ABC and 75% for GCB categorisation and positive predictive value of 81% versus 82%, respectively. Lymph2Cx-based COO classification performed superior to Hans algorithm in predicting OS (log rank test, p=0.017 vs p=0.212).

CONCLUSIONS:

Our report show that current IHC-based protocols for COO classification of DLBCL at UKM Malaysia are in line with previously reported results and marked variation in preanalytical factors do not critically impact Lymph2Cx assay quality.

KEYWORDS:

Cell of origin; DLBCL -ACB subtype; DLBCL -GCB subtype; Diffuse large B-cell lymphoma; Hans algorithm.; Lymph2Cx

PMID:
28775174
DOI:
10.1136/jclinpath-2017-204548
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center