Incidence of homogeneously staining regions in non-Hodgkin lymphomas

We report a series of 86 non-Hodgkin's lymphomas (NHL) studied cytogenetically in which two cases with a homogeneously staining region (HSR) located on chromosome 19 and on chromosome 1, respectively, were observed. The low incidence detected (2.3%) suggests that HSR are rare events in NHL. An oncogenetic amplification study was performed with probes for genes that are currently known to undergo amplification and with probes for two genes located on chromosome 19q (AKT2 and BCL-3). We detected no amplification except for AKT2 putative oncogene in the lymphoma in which the HSR was located on chromosome 19. Because amplification of AKT2 putative oncogene has been detected in ovarian carcinomas bearing HSR and in this case NHL, we believe that this gene may be implicated in the pathogenesis of other neoplasias in cooperation with other genes. Further investigation is needed to confirm the low incidence of HSR in NHL and the origin of the amplified material.