Trends in hematopoietic stem cell utilization and cost of cryopreservation

Abstract

Abstract Autologous stem cell transplantation (ASCT) is the standard of care treatment for multiple myeloma. Standard ASCT procedures collect hematopoietic stem cells (HPSC) in excess for multiple transplants due to reports of high mobilization failure and unsuccessful ASCT collections following myeloablative treatments. Cost analysis studies estimate that one year of cryopreservation and one day of HPSC collection would each cost $5000 per patient. Limited data is available on the usage of the second transplant and the storage costs of non-transplanted products. This study evaluates the utilization of cryopreserved HPSC products and calculates the cost of cryopreservation. A retrospective chart review study of a cohort of 240 deceased MM patients, who received ASCT between January 2010 to December 2015. Demographic and clinical data were obtained from the laboratory and electronic medical record. The cohort was categorized into two groups, with 130 patients in Group 1 (≤60 years) and 110 patients in Group 2 (>60 years). Cumulative incidence of a second transplant was computed from the life table using the Kaplan Meier method. The cost of cryopreservation was calculated based on the time HPSC products remained in the freezers before disposal. PBSC was mobilized using Granulocyte Colony Stimulating Factor (GCSF), or GCSF and Mozobil. The average age of patients at first collection is 61 (IQR: 54-66) years and the average age of death is 64 (IQR: 58 -70) years. The average life span of patients after receiving the first transplant is 3 (IQR: 2-5) years. The average number of collection days is 2 (IQR: 1-3). 65 patients had 1-day collections, 105 had 2-day collections and 70 had ≥3-day collections. 175 patients (73%) had >1 day collection. Only 22 patients (9%) received a second transplant and 18 of them (82%) were in Group 1 (≤60). The cumulative incidence of a second transplant by 5 years is 23% for Group 1 and 4% for Group 2. Two-transplant collections required 492 days of apheresis with an overall cost of $2,500,000; however, one-transplant collections would cost $1,400,000 for 279 apheresis days. The median cost of cryopreservation for each patient who did not receive the second transplant is $15,000 (IQR: $8000 - $25,000). Therefore, the estimated cost for all patients in the study is $3,600,000 until the disposal of HPSC products. The incidence of a second transplant is low across all patients and significantly lower in patients greater than 60 years of age. Cryopreserved stem cell products remain under-utilized, leading to substantial financial burden. The duration of HPSC collection and cryopreservation must be re-evaluated for future treatment plans. Institutional policies should be revised based on the utilization trend to lower the operational cost of storage.