Detection of Pre-Transplant Clonal Cytogenetic Abnormalities in Stem Cells Used for Autologous Stem Cell Transplant in Relapsed Non-Hodgkin Lymphoma Is a Predictor of Relapse

Autologous stem cell transplant is used for chemotherapy sensitive relapsed Non-Hodgkin Lymphoma (NHL). Patients who receive an autologous stem cell transplant after high dose chemotherapy for relapsed NHL have significantly superior survival compared to those receiving conventional chemotherapy. Relapsed patients who achieve a second remission are treated with myeloablative chemotherapy followed by autologous stem cell transplant. These patients can achieve 5-year event free survival close to 50% and 5-year overall survival of greater than 50%. We performed a retrospective analysis of our center’s transplant data and reviewed pre-transplant cytogenetic analysis on the patient’s collected stem cells. 259 patients underwent autologous stem cell transplant from 1998 through 2007 for relapsed NHL. Cytogenetic evaluations of the patient’s pre-transplant stem cells had been done to look for evidence of MDS or characteristics of their lymphoma. Clonal cytogenetic abnormalities were found in 12 of the 259 patients. Two of these patients died within 45 days of transplant without evidence of relapse. One from infection and a second from non-treatment related causes. Nine of the remaining 11 (81%) patients with clonal cytogenetic abnormalities have relapsed and died. All patients relapsed with their original lymphoma. The cytogenetic abnormalities were varied. Out of the 9 relapses, 3 had cytogenetic abnormalities in the stem cells that are associated with lymphoma, 2 that are associated with AML, 1 that is associated with MDS, and 2 were abnormalities whose significance was unknown. In one patient cytogenetic changes of the original lymphoma were identified. The patients that had clonal cytogenetic abnormalities in their collected stem cells had an 81% relapse rate as opposed to 30% in the patients whose stem cells had a normal karyotype. Our findings show that cytogenetic changes in the collected stem cells are associated with a higher rate of lymphoma relapse.