Experience with the BIOMED-2 standardized polymerase chain reaction protocol for immunoglobulin and T- cell receptor clonality analysis in the Instituto Nacional de Cancerología, Colombia.

Introduction: The European BIOMED-2 consortium was created to evaluate clonality in lymphoproliferations that are difficult to diagnose. In Colombia, the implementation of these tests began in 2015 at the Instituto Nacional de Cancerología E.S.E., Bogotá. Objectives: To determine the behavior of the rearrangement tests for lymphoid clonality and the difficulties of its implementation in our field through a series of retrospective and consecutive cases of lymphoid proliferation subjected to the BIOMED-2 protocols. Materials and methods: Clinical and histological data and the results of the rearrangement analysis of all cases of lymphoid proliferation subjected to the BIOMED-2 protocols between February 2015 and May 2019 were collected from clinical histories. Results: We recovered 132 samples from which 47 corresponded to reactive lymphoid hyperplasias, 62 to T lymphomas, 19 to B lymphomas, and three to lymphoid neoplasms of unestablished lineage. Only in one case did DNA extraction fail. According to these results, the greatest diagnostic difficulty for the pathologist was the analysis of T lymphoid infiltrates, most of which (44) were skin lesions. Conclusions: Clonality tests can be used in tissues of different quality to help in the diagnosis of lymphoid proliferations that are difficult to classify. It is important to implement and interpret them in an interdisciplinary way considering each case separately.