Risk of febrile neutropenia among patients with multiple myeloma or lymphoma who undergo inpatient versus outpatient autologous stem cell transplantation: a systematic review and meta-analysis

Background: Outpatient autologous stem cell transplantations (ASCTs) in multiple myeloma and lymphoma patients have been shown to reduce the overall costs and improve the quality of life relative to inpatient ASCTs. This systematic review and meta-analysis was performed with the aim of comprehensively comparing the risk of febrile neutropenia developing in ASCT outpatients and inpatients who have multiple myeloma or lymphoma.

Methods: To be eligible for the meta-analysis, studies needed to be either randomized, controlled studies or cohort studies. They also need to have two groups of patients with multiple myeloma or lymphoma who underwent ASCT, with the treatment being provided to one group in an outpatient setting and to the other on an inpatient basis. The studies had to report our primary outcome of interest, the rate of febrile neutropenia after stem cell infusion, for both groups. The Mantel-Haenszel method was used to pool the effect estimates and 95% confidence intervals of each study.

Results: From 9 eligible studies, a total of 1940 patients were included in the meta-analysis. Contrary to conventional concerns, the patients who underwent the outpatient ASCT had a significantly lower risk of developing febrile neutropenia than those admitted for ASCT, with a pooled odds ratio (OR) of 0.44 (95% confidence interval [CI]: 0.29-0.65; p < 0.0001; I² = 52%). The risk of septicemia was also significantly lower for the outpatients than the inpatients, with a pooled OR of 0.40 (95% CI: 0.16-0.97; p = 0.04; I² = 23%). Additional analyses found that the odds of having grade 2-3 mucositis and transplant-related mortality were numerically lower for the outpatient group, although the pooled result was not statistically significant. The odds of surviving at 2-3 years was also numerically higher for the ASCT outpatients, but the difference did not reach statistical significance.

Conclusions: This study found a significantly lower odds of developing febrile neutropenia and septicemia among patients with multiple myeloma and lymphoma who received an outpatient ASCT than among those who had an inpatient ASCT.