Contributions
Abstract: PB2341
Type: Publication Only
Background
Histopathologic study is considered nowadays the technique of choice for the diagnosis of pathology in lymph nodes. However, it has limitations: subjective analysis, limited reproducibility, reduced amount of reagents for determining antigenic expression and considerable consumption of time and human resources. Cytomorphologic examination and multiparametric flow citometry (C-FCM) may solve some of these obstacles: faster diagnosis and multiparametric analysis with qualitative and quantitative characterization of different cell antigens expression. Limitations of this technique are: impossibility to evaluate lymph node architecture and cellular damage during processing.
Aims
Our aim was to evaluate in our centre the diagnostic value of C-FCM for oncohematologic diseases in lymphoid tissues and its accuracy in subclassifying Non Hodgkin Lymphomas (NHL), apart from indicating in which circumstances this technique was insufficient.
Methods
From 2015 to 2017, we prospectively analyzed by C-FCM 176 lymph tissue biopsy specimens, mainly obtained (76.7% (135/176)) by large needle biopsy of lymph node. Every sample was evaluated by cytomorphology of touch imprints stained with May-Grümwald-Giemsa and by FCM. Likewise, a part of the same sample was evaluated by histopathology. Median age was 60 years (1-91): 94 male (53.4%) and 82 female (46.6%). 54 (31%) had previous lymphoma history. Statistical analysis was performed employing G-STAT program (version 2.0.1, Biometrics Department of GlaxoSmithKline).
Results
C-FMC detected neoplastic disorders in 120 (68.2%) samples: 82 NHL (67.8%), 11 Hodgkin Lymphomas (HL, 9%), 26 malignant non hematologic neoplasms (NHN 21.5%) and 1 Acute Myeloid Leukemia (0.8%). Sensitivity and specificity were 85% and 83%. Positive predictive value (PPV) and negative predictive value (NPV) were 94.2% and 63.6%, respectively. Sensitivity and NPV increased to 93% and 86% when HL, NHN and T-cell / histiocyte-rich-B-cell lymphomas (TCRBL) were excluded from the analysis. 71/82 LNH (86.6%) were defined according to the 2008 World Health Organization (WHO) classification of hematolymphoid neoplasms, with a concordance of 78% with respect to the histopathological study.
Conclusion
C-FCM provides very valuable information regarding diagnosis of pathology in lymph nodes, showing high sensitivity and specificity. C-FCM is especially useful in NHL, allowing their sub-classification according to WHO criteria with a concordance of 78%. Moreover, being a faster technique compared to histopathology, while keeping a high PPV, it makes it easier to take quick therapeutic decisions, which is relevant in aggressive diseases. However, in NHN, HL and TCRBL, the utility of this technique relies on excluding the most usual NHL diagnosis, remaining histopathology the gold standard for diagnosis.
Session topic: 19. Non-Hodgkin lymphoma Biology & Translational Research
Keyword(s): flow cytometry, lymphoma
Abstract: PB2341
Type: Publication Only
Background
Histopathologic study is considered nowadays the technique of choice for the diagnosis of pathology in lymph nodes. However, it has limitations: subjective analysis, limited reproducibility, reduced amount of reagents for determining antigenic expression and considerable consumption of time and human resources. Cytomorphologic examination and multiparametric flow citometry (C-FCM) may solve some of these obstacles: faster diagnosis and multiparametric analysis with qualitative and quantitative characterization of different cell antigens expression. Limitations of this technique are: impossibility to evaluate lymph node architecture and cellular damage during processing.
Aims
Our aim was to evaluate in our centre the diagnostic value of C-FCM for oncohematologic diseases in lymphoid tissues and its accuracy in subclassifying Non Hodgkin Lymphomas (NHL), apart from indicating in which circumstances this technique was insufficient.
Methods
From 2015 to 2017, we prospectively analyzed by C-FCM 176 lymph tissue biopsy specimens, mainly obtained (76.7% (135/176)) by large needle biopsy of lymph node. Every sample was evaluated by cytomorphology of touch imprints stained with May-Grümwald-Giemsa and by FCM. Likewise, a part of the same sample was evaluated by histopathology. Median age was 60 years (1-91): 94 male (53.4%) and 82 female (46.6%). 54 (31%) had previous lymphoma history. Statistical analysis was performed employing G-STAT program (version 2.0.1, Biometrics Department of GlaxoSmithKline).
Results
C-FMC detected neoplastic disorders in 120 (68.2%) samples: 82 NHL (67.8%), 11 Hodgkin Lymphomas (HL, 9%), 26 malignant non hematologic neoplasms (NHN 21.5%) and 1 Acute Myeloid Leukemia (0.8%). Sensitivity and specificity were 85% and 83%. Positive predictive value (PPV) and negative predictive value (NPV) were 94.2% and 63.6%, respectively. Sensitivity and NPV increased to 93% and 86% when HL, NHN and T-cell / histiocyte-rich-B-cell lymphomas (TCRBL) were excluded from the analysis. 71/82 LNH (86.6%) were defined according to the 2008 World Health Organization (WHO) classification of hematolymphoid neoplasms, with a concordance of 78% with respect to the histopathological study.
Conclusion
C-FCM provides very valuable information regarding diagnosis of pathology in lymph nodes, showing high sensitivity and specificity. C-FCM is especially useful in NHL, allowing their sub-classification according to WHO criteria with a concordance of 78%. Moreover, being a faster technique compared to histopathology, while keeping a high PPV, it makes it easier to take quick therapeutic decisions, which is relevant in aggressive diseases. However, in NHN, HL and TCRBL, the utility of this technique relies on excluding the most usual NHL diagnosis, remaining histopathology the gold standard for diagnosis.
Session topic: 19. Non-Hodgkin lymphoma Biology & Translational Research
Keyword(s): flow cytometry, lymphoma