Article

Prognostic implications of BCL6 rearrangement in uniformly treated patients with diffuse large B-cell lymphoma--a Nordic Lymphoma Group study.

Department of Oncology, Lund University Hospital, SE-221 85 Lund, Sweden.
International Journal of Oncology (Impact Factor: 2.66). 02/2002; 20(1):161-5. DOI: 10.3892/ijo.20.1.161
Source: PubMed

ABSTRACT The purpose of this study was to investigate the prognostic implications of BCL6 rearrangement in a uniformly treated population of patients with diffuse large B-cell lymphoma (DLBCL) and to characterise the relationship between BCL6 rearrangement and prognostic factors. A total of 269 patients with DLBCL entered a randomised trial comparing the chemotherapy regimen CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) to the MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone, bleomycin) regimen. In 44 cases, frozen tissue was available for assessment of BCL6 status by Southern blot analysis. BCL6 was rearranged in six of 43 evaluable cases (14%), and was associated with elevated lactate dehydrogenase (LDH), and a higher patient age. No association between BCL6 status and expression of BCL2, Ki-67 or TP53 was found. Patients presenting with BCL6 rearrangement displayed a weak trend towards better overall and failure-free survival (67 and 67% at 5 years), compared to patients with germline BCL6 (63 and 52%), but the difference was not statistically significant. In accordance with previously published series, the presence of BCL6 rearrangement does not define a prognostically distinct subgroup of DLBCL. Assessment of BCL6 status may, however, be of clinical interest when related to other prognostic variables.

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DLBCL on jaoteltu hyväennusteisiin itukeskusperäisiin ja huonoennusteisiin ei-itukeskusperäisiin alatyyppeihin. Näiden alatyyppien ennusteellinen merkitys on kuitenkin ollut epäselvä immunokemoterapian aikakaudella. Tämän väitöskirjan tavoitteena oli selventää immunohistokemiallisesti määriteltyjen biologisten ennustetekijöiden merkitys immunokemoterapiaa saaneilla DLBCL potilailla. Tutkimuksessa todettiin että aikaisemmin esitellyn algoritmin mukaan (CD10, BCL6 ja MUM1/IRF4) itukeskus ja ei-itukeskus alatyyppistä lymfoomaa sairastavilla potilailla ei ollut eroa taudinkulussa. Luokittelulla ei myöskään ollut ennusteellista merkitystä potilailla, joiden hoitona oli ollut korkea-annossolunsalpaajahoito ja autologinen kantasolusiirto. Sen sijaan, mikäli ei-itukeskus alatyyppi määriteltiin väitöskirjassa kuvatun uuden algoritmin mukaan (MUM1/IRF4 ja FOXP1) voitiin todeta, että tämän alatyypin omaavilla potilailla oli immunokemoterapian jälkeen huonompi ennuste kuin muilla potilailla. Väitöskirjassa tutkittiin lisäksi immunohistokemiallisesti BCL2 ja FOXP1 proteiinien ilmentyminen lymfoomakudoksessa ja niiden ennusteellista merkitystä immunokemoterapiaa saaneilla DLBCL potilailla. Tutkimuksessa todettiin, että potilailla oli huono ennuste, jos BCL2 proteiinia todettiin lymfoomakudoksessa. FOXP1 proteiinilla ei ollut ennusteellista merkitystä. Väitöskirjan tulokset osoittavat, että immunokemoterapiahoidetuilla DLBCL potilailla voidaan tunnistaa huonoennusteinen ei-itukeskusperäinen alatyyppi uudella immunohistokemiallisella algoritmilla. Lisäksi huonoennusteiseen taudinkuvaan viittaa BCL2 ilmentyminen. Taudin biologisista piirteistä tarvitaan silti täydentävää tietoa, ennen kuin nämä esitellyt tekijät voivat ohjata hoidon valintaa.
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