described in the WHO classification, was not present. In addition, in the analysis of survival we observed LCR as an independent prognostic factor. All the baseline characteristics were not different between kappa and lambda groups. Conse- quently, we suggest that the expression of surface immunoglobulin light chain should be evaluated as a prog- nostic factor in a larger cohort of MCL to confirm our results, which have not been described previously. Author contributions MLG, CV, SOZ, KJG and SC designed the study; collected, analysed and interpreted data; and wrote the initial draft of manuscript. MR, PLPR, MTOC, IL, MLP, MS and FC con- tributed to the study design, participated in interpretation of data and critically revised the manuscript for intellectual con- tent and approved the final version of the manuscript for publication. Conflict of interest CV, SOZ, KJG, SC, MLG, MR, PLPR, MTOC, IL, MLP, MS and FC: None. Carolina Villegas Da Ros Mariano Linares Garcia Sebastian Ortiz Zuluaga Karla Javier Gonzalez Sofia Costa Monica Roig Pedro Luis Perez Rodriguez Mayte Orero Castello Irene Luna Maria L opez-Pav  ıa Magdalena Sanchez Felix Carbonell Department of Haematology, Hospital General Universitario de Valen- cia, Valencia, Spain. E-mail: caro.villegas.daros@gmail.com Keywords: mantle cell lymphoma, MCL International Prognostic Index, prognostic factors First published 29 April 2017 doi: 10.1111/bjh.14109 References Campo, E., Raffeld, M. & Jaffe, E.S. (1999) Man- tle-cell lymphoma. Seminars in Hematology, 36, 115–127. Chihara, D., Asano, N., Ohmachi, K., Kinoshita, T., Okamoto, M., Maeda, Y., Mizuno, I., Mat- sue, K., Uchida, T., Nagai, H., Nishikori, M., Nakamura, S., Ogura, M. & Suzuki, R. (2015) Prognostic model for mantle cell lymphoma in the rituximab era: a nationwide study in Japan. British Journal of Haematology, 170, 657–668. Hoster, E., Dreyling, M., Klapper, W., Gisselbrecht, C., vanHoof, A., Kluin-Nelemans, H. C., Pfre- undschuh, M., Reiser, M., Metzner, B., Einsele, H., Peter, N., Jung, W., W€ ormann, B., Ludwig, W. D., D€ uhrsen, U., Eimermacher, H., Wandt, H., Hasford, J., Hiddemann, W. & Unterhalt, M.; for the German Low Grade Lymphoma Study Group (GLSG) and the European Mantle Cell Lymphoma Network (2008) A new prog- nostic index (MIPI) for patients with advanced- stage mantle cell lymphoma. Blood, 111, 558– 565. Ondrejka, S.L., Lai, R., Smith, S.D. & His, E.D. (2011) Indolent mantle cell leukemia: a clinco- pathological variant characterized by isolated lymphocytosis, interstitial bone marrow involve- ment, kappa light chain restriction, and good prognosis. Haematologica, 96, 1121–1127. Swerdlow, S.H., Habeshaw, J.A., Murray, L.J., Dhaliwal, H.S., Lister, T.A. & Stansfeld, A.G. (1983) Centrocytic lymphoma: a distinct clinico- pathologic and immunologic entity. American Journal of Pathology, 113, 181–197. Swerdlow S.H., Campo E., Harris N.L., Jaffe E.S., Pileri S.A., Stein H., Thiele J. & Vardiman J.W., eds. (2008) WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues. IARC, Lyon, France. Tolksdorf, G., Stein, H. & Lennert, K. (1980) Mor- phological and immunological definition of a malignant lymphoma derived from germinal- centre cells with cleaved nuclei (centrocytes). British Journal of Cancer, 41, 168–172. DNA demethylating therapy reverts mesenchymal stromal cells derived from high risk myelodysplastic patients to a normal phenotype Myelodysplastic syndromes (MDS) are clonal stem cell disorders characterized by ineffective haematopoiesis in one or more bone marrow (BM) lineages and an increased tendency of transformation to acute myeloid leukaemia (AML) (Corey et al, 2007). The BM microenvironment supports haematopoietic stem cells (HSC), enabling them to propagate and differentiate into committed haematopoietic progenitors and the whole repertoire of peripheral blood Correspondence 818 ª 2016 John Wiley & Sons Ltd British Journal of Haematology, 2017, 177, 806–822