Benjamin Johansson1, Helka Sahi2, Virve Koljonen3, Tom Böhling1. 1. Department of Pathology, Helsinki University and HUSLAB, Helsinki, Finland. 2. Department of Dermatology and Allergology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland. 3. Department of Plastic Surgery, Helsinki University Hospital, Helsinki, Finland.
Abstract
BACKGROUND: Merkel cell carcinoma (MCC) tumor samples frequently express B-lymphoid lineage markers. However, the reasons for expression of specific B-lymphoid lineage markers are still unclear. We studied the expression of TdT and PAX5 (two B-cell lymphoid lineage markers) in a large pool of MCC tissue microarray samples. METHODS: Immunoexpression and staining intensities of TdT and Pax-5 were statistically correlated with patient, tumor, Merkel cell polyomavirus (MCV), and disease-specific parameters. RESULTS: In a cohort of 117 MCC patients and their corresponding tumor samples, TdT was expressed in 37 (31.6%) samples and PAX5 in 26 (22.2%). Simultaneous immunostaining for TdT and PAX5 was observed in 13 (11.1%) samples. A statistically significant relationship was observed between MCV virus copy number and positive TdT expression (P = 0.0056). Similarly, a significant relationship was also observed between positive TdT and tumor MCV virus positivity (P = 0.000495). CONCLUSION: We observed frequent TdT and PAX5 immunoexpression in MCC tumor samples. However, simultaneous immunoexpression of these markers was scarce. TdT expression was statistically significantly associated with MCV positivity. The absence of a statistically significant association between tumor parameters and disease progression markers undermines the systemic use of these markers in clinical practice.
BACKGROUND:Merkel cell carcinoma (MCC) tumor samples frequently express B-lymphoid lineage markers. However, the reasons for expression of specific B-lymphoid lineage markers are still unclear. We studied the expression of TdT and PAX5 (two B-cell lymphoid lineage markers) in a large pool of MCC tissue microarray samples. METHODS: Immunoexpression and staining intensities of TdT and Pax-5 were statistically correlated with patient, tumor, Merkel cell polyomavirus (MCV), and disease-specific parameters. RESULTS: In a cohort of 117 MCC patients and their corresponding tumor samples, TdT was expressed in 37 (31.6%) samples and PAX5 in 26 (22.2%). Simultaneous immunostaining for TdT and PAX5 was observed in 13 (11.1%) samples. A statistically significant relationship was observed between MCV virus copy number and positive TdT expression (P = 0.0056). Similarly, a significant relationship was also observed between positive TdT and tumorMCV virus positivity (P = 0.000495). CONCLUSION: We observed frequent TdT and PAX5 immunoexpression in MCC tumor samples. However, simultaneous immunoexpression of these markers was scarce. TdT expression was statistically significantly associated with MCV positivity. The absence of a statistically significant association between tumor parameters and disease progression markers undermines the systemic use of these markers in clinical practice.
Authors: Abraham C van Wyk; Zaheer Moolla; Ahmed I Motala; Riyaadh Roberts; Nivesh A Chotey; Hoosen I Lakhi; Jürgen C Becker Journal: Clin J Gastroenterol Date: 2022-06-28