Clinical and Biological Characteristics of Medullary and Extramedullary Plasma Cell Dyscrasias

Snjezana Janjetovic; Philipp Lohneis; Axel Nogai; Derya Balci; Leo Rasche; Doris Jähne; Carsten Bokemeyer; Georgia Schilling; Igor Wolfgang Blau; Martin Schmidt-Hieber

doi:10.3390/biology10070629

Clinical and Biological Characteristics of Medullary and Extramedullary Plasma Cell Dyscrasias

Biology (Basel). 2021 Jul 6;10(7):629. doi: 10.3390/biology10070629.

Authors

Snjezana Janjetovic^{1

2}, Philipp Lohneis^{3

4}, Axel Nogai⁵, Derya Balci^{5

6}, Leo Rasche⁷, Doris Jähne⁸, Carsten Bokemeyer¹, Georgia Schilling^{1

9}, Igor Wolfgang Blau^{5

10}, Martin Schmidt-Hieber^{2

5

11}

Affiliations

¹ Department of Oncology, Hematology and Bone Marrow Transplantation with Section Pneumology, University Clinic Hamburg-Eppendorf, 20251 Hamburg, Germany.
² Clinic of Hematology and Stem Cell Transplantation, HELIOS Clinic Berlin-Buch, 13125 Berlin, Germany.
³ Institute of Pathology, Charité University Medicine Berlin, 10117 Berlin, Germany.
⁴ Institute of Pathology, University of Cologne, 50923 Cologne, Germany.
⁵ Clinic of Hematology, Oncology and Tumor Immunology, Campus Benjamin Franklin, Charité University Medicine Berlin, 12203 Berlin, Germany.
⁶ St. Joseph Hospital Berlin-Tempelhof, 12101 Berlin, Germany.
⁷ Department of Internal Medicine II, University Hospital Würzburg, 97080 Würzburg, Germany.
⁸ Institute of Pathology, HELIOS Clinic Berlin-Zehlendorf, 14165 Berlin, Germany.
⁹ Department of Hematology, Oncology, Palliative Care and Rheumatology, Asklepios Hospital Altona, Asklepios Tumorzentrum, 22763 Hamburg, Germany.
¹⁰ Clinic of Hematology, Oncology and Tumor Immunology, Campus Virchow Klinikum, Charité University Medicine Berlin, 10117 Berlin, Germany.
¹¹ Clinic of Hematology and Oncology, Carl-Thiem-Klinikum, 03048 Cottbus, Germany.

Abstract

Background: Extramedullary plasma cell (PC) disorders may occur as extramedullary disease in multiple myeloma (MM-EMD) or as primary extramedullary plasmocytoma (pEMP)/solitary osseous plasmocytoma (SOP). In this study, we aimed to obtain insights into the molecular mechanisms of extramedullary spread of clonal PC. Methods: Clinical and biological characteristics of 87 patients with MM-EMD (n = 49), pEMP/SOP (n = 20) and classical MM (n = 18) were analyzed by using immunohistochemistry (CXCR4, CD31, CD44 and CD81 staining) and cytoplasmic immunoglobulin staining combined with fluorescence in situ hybridization (cIg-FISH). Results: High expression of CD44, a cell-surface glycoprotein involved in cell-cell interactions, was significantly enriched in MM-EMD (90%) vs. pEMP/SOP (27%) or classical MM (33%) (p < 0.001). In addition, 1q21 amplification by clonal PC occurred at a similar frequency of MM-EMD (33%), pEMP/SOP (57%) and classical MM (44%). Conversely, del(17p13), t(4;14) and t(14;16) were completely absent in pEMP/SOP. Besides this, 1q21 amplification was identified in 64% of not paraskeletal samples from MM-EMD or pEMP compared to 9% of SOP or paraskeletal MM-EMD/pEMP and 44% of classical MM samples, respectively (p = 0.02). Conclusion: Expression of molecules involved in homing and cytogenetic aberrations differ between MM with or without EMD and pEMP/SOP.

Keywords: cytogenetics; extramedullary; immunohistochemistry; multiple myeloma; plasma cell disorder.