Compare The Outcome Of Patients With Hematological Malignancies Treated With Allogeneic Stem Cell Transplant In Patients Age Over 50 Conditioned With Reduce Intensity Regimens With Those Under 50 Conditioned With Standard Intensity Regimen In a Rural University Hospital – A Single Institution Experience

Abstract Background Majority of hematological malignancies occurs in older individuals and most can only be cured with high dose chemotherapy followed by stem cell transplantation. Unfortunately these patients who need transplantation the most cannot tolerate chemotherapy well. Development of reduced-intensity transplant regimens has allowed older patients be treated with allogeneic transplantation. Aims To compare the outcome of allogeneic hematopoietic stem cell transplantation in patients age over 50 conditioned with reduce dose intensity regimens with those under 50 conditioned with standard dose intensity regimen Methods We analyzed retrospectively the data in a cohort of 50 consecutive patients with hematological malignancies treated with allogeneic stem cell transplant. We divided the patients into two groups, those under 50 years and those over 50 years. Those under 50 years received standard dose conditioning regimen, while those over 50 years received reduced dose regimen except for one patient. Cyclosporine and standard dose methotrexate was used as GVHD prophylaxis in patients under 50yrs while Cyclosporine and low dose methotrexate was used in patients over 50. Type of hematological malignancies, disease condition at transplant, type of transplant, conditioning regimen, dose of CD34+ stem cell and nucleated cell infused, day to myeloid and platelet engraftment and day 90 mortality is shown in the table. Patients who received unrelated donor transplant received ATG. Five high risk patients received peri-transplant Keratinocyte Growth Factor. All patients received G-CSF beginning day-0. Patients Patients > 50 years old Number of Patients 30 20 Age 18 to 46 years (Median 31 yrs) 50 to 69 years (Median 57.5 yrs) Indication for transplant Acute Leukemia & MDS (18), Aplastic Anemia (3), Chronic Leukemia (4), Lymphoma (5) Acute Leukemia & MDS (14), Myelofibrosis (1), Chronic Leukemia (1), Lymphoma (4) Type of transplant a) Sibling - 13 b) MUD – 13 (43%) c) Cord Blood/Double Cord- 2/2 a) Sibling - 13 b) MUD – 6 (30%) c) Double Cord blood - 1 Disease Status at Transplant a) Remission - 14 b) Active – 15 (50%) c) Unknown - 1 a) Remission - 5 b) Active – 14 (70%) c) Unknown - 1 Conditioning Regimen Bu/CTX (11), Bu/Flu (9), CTX/TBI (2), ATG/CTX (2) Melphalan Containing Regimen (6). Mel/Flu (9), Bu/Flu (8), CTX/TBI (1), Bu/CTX (I), Mel/Thio (1). Dose of CD34+ hematopoietic stem cell infused Range 0.12 x106 to 15.83 x 106 cells/kg (median 3.15 x 106 cells/kg). Range 1.51 x106 to 9.08 x 106 cells/kg (median 4.21 x 106 cells/kg). Dose of Nucleated cell infused Range 0.22 x 108to 41.46 x 108 cells/kg (median 9.37 x 108nucleated cells/kg). Range 5.19 x 108to 18.32 x 108 cells/kg (median 9.08 108nucleated cells/kg). Day of Myeloid Engraftment Range 10-30 days. Median 14 days Range 9 to 21 days. Median 14 days Day of Platelet Engraftment Range (Median day) Range 10 -42 days. (Median 16 days) Range 10-68 days. (Median 18 days) Engraftment Failure 2 Patients (both received cord blood) 0 Patients Early mortality (day 90) 9/30 Patients (30%) 9/20 Patients (45%) Results 43% of patient 50). Two patients who received cord blood under 50 years group had engraftment failure. Ninety day mortality was 30% in those under 50 vs. 45% in those over 50. Conclusions Reduced intensity allogeneic stem cell transplantation is feasible and well tolerated in older patients with hematological malignancies with good engraftment however with high early (day 90) mortality. 70% of the patients had active disease at the time of transplant which could account for their high mortality. To prevent early peri-transplant mortality patients with active disease should not go to transplant or should be treated with newer chemotherapy or targeted agents to bring them into remission prior to transplantation Disclosures: No relevant conflicts of interest to declare.