Deletions at 11q23 in different lymphoma subtypes

Background and Objectives. Chromosome band 11q23 is frequently deleted in v arious types of neoplasm. The region represented by yeast artificial chromo some (YAC) clone 755b11 at 11q23 has been shown to be the minimal common re gion of deletion in mantle cell lymphoma (MCL) and B-cell chronic lymphocyt ic leukemia (B-CLL). The aim of the study was to determine the frequencies of 11q23 deletion in different lymphoma subtypes. Design and Methods. We performed fluorescence in situ hybridization (FISH) analysis with YAC755b11 on either peripheral blood or lymph node biopsy (LN ) specimens of patients diagnosed as having MCL (47), CLL/small lymphocytic lymphoma (SLL) (62), diffuse Targe cell lymphoma (DLCL) (17), follicular l ymphoma (FL) (9), and Hodgkin's disease (HD) (11). Fifteen cases of reactiv e or normal lymph node biopsies were studied as controls. Results. Forty of the 161 (25%) samples exhibited deletions in the region r epresented by YAC755b11. The 11q23 deletion was found only in MCL (23, 49%) , CLL/SLL (13, 21%) and DLCL (4, 24%). Three cases were classified as Richt er's syndrome and they all exhibited the deletion at 11q23. The deletion fr equencies in the blood specimens of typical CLL (30%) and lymph node specim ens of CLL/SLL (13%) were remarkably different. Interpretation and Conclusions. Our study demonstrated that the 11q23 delet ion is not common in lymphomas other than MCL, CLL and DLCL. It also showed the possible correlation of the 11q23 deletion with the transformation of localized lymphoma to CLL, and with the development of Richter's syndrome. (C) 2000, Ferrata Storti Foundation.