Safety of Outpatient Autologous Hematopoietic Cell Transplantation (AuHCT) for Multiple Myeloma and Lymphoma

AuHCT is commonly an inpatient procedure. Due to improvements in supportive care, many centers now perform AuHCT on an outpatient basis.  We compared the outcome of 95 outpatients (OP) and 135 inpatients (IP) that underwent a first AuHCT from July 2009 to December 2012 for myeloma or lymphoma using melphalan or BEAM conditioning at a single center.  Selection for OP AutoHCT was based on expected compliance, proximity to the cancer center for daily visits, 24-hour caregiver support, and favorable performance status and co-morbidity profile.  Both groups received the same chemotherapy or supportive care, except that the OP group received more aggressive prophylactic antibiotic support during neutropenia and received pegfilgrastim on day +1.  The IP group received daily filgrastim starting on day +5.

The OP and IP cohorts were similar in terms of primary disease (myeloma vs. lymphoma), median age, gender, and chemo-sensitivity pre-transplant.  Karnofsky Performance Status (KPS) was less favorable in the IP cohort with KPS ≤80 in 36% vs. 6% in the OP cohort (p<0.001).  There was a trend toward less favorable Hematopoietic Cell Transplant Co morbidity Index (HCT-CI) in the IP cohort as well with 53% of the patients having HCT-CI >/=3 vs. 40% in the OP cohort (p=0.060). With regard to transplant characteristics, OP and IP received a similar CD34 cell dose (4.4 vs. 4.6 x 10⁶/kg, respectively, p=0.581). Hematopoietic recovery occurred earlier in the OP cohort, with median time to neutrophil recovery of 10 vs. 11 days (p<0.001) and median time to platelet recovery of 19 vs. 20 days (p=0.053).  For OP AuHCT, overall 51% were never admitted; for patients transplanted in 2011-2012 this figure was 61%.  For the OP that were admitted, median length of stay was 9 days.   In comparison, the IP AuHCT patients had a median length of stay of 19 days.

Grade 3-4 non-hematologic toxicities occurred in 29% of both the OP and IP cohorts. There were no significant differences in specific adverse events between the two cohorts, including febrile neutropenia, bacteremia, Clostridium difficile infections, central venous line complications, and engraftment syndrome.  Non-relapse mortality at one year was 0% in the OP cohort and 1.5% in the IP cohort (p=0.327).  Two year PFS was 62% for OP vs. 54% for IP (p=0.155).  One and two year OS was 97% and 83% for OP vs. 91% and 80% for IP, respectively (p=0.271).

We conclude that, with careful patient selection and minor modification to the management of neutropenia, OP AuHCT can result in excellent outcomes for myeloma and lymphoma patients.  OP AuHCT also offers benefit for patients in terms of enhanced comfort, fewer days in the hospital, and decreased exposure to sick contacts.  Lastly, OP AuHCT is beneficial to transplant centers due to decreased hospital resource utilization.