Clinical study of late-onset hemorrhagic cystitis after allo-HSCT without in vitro T-cell depletion

This study is to investigate the hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) without in vitro T-cell depletion. Patients receiving allo-HSCT in 2019 were enrolled. The occurrence and clinical characteristics of HC after HLA-identical HSCT and haploidentical HSCT were retrospectively analyzed. BK, JC, cytomegalovirus, and other viruses were monitored when HC occurred. Conventional HC treatment was performed. Additionally, 5 cases of severe refractory HC were treated with adipose-derived mesenchymal stem cell (ADSC) besides conventional HC treatment. Totally, 54 patients with allo-HSCT were enrolled, including 12 cases with HLA-identical HSCT and 42 cases with haploidentical HSCT. Among them, 17 developed late-onset HC (LOHC). There was no early-onset HC. The median onset time was 33.5 (9-189) days, with a median duration of 19 (5-143) days. There were 8 cases of grade III HC and 2 cases of grade IV HC. The cumulative incidence of LOHC in 54 patients was 29.6%, and the cumulative incidence of LOHC in 42 patients with haploidentical HSCT was 40.5%. The 1-year expected progression-free survival (PFS) of 26 patients without HC was 86.6%, and the 1-year expected PFS of 16 HC patients was 74.5%. However, there was no statistically significant difference (P = .326). The urine BK virus of 14 patients was positive, with the lowest of 1.98 x 10(5) copies/mL, and the highest of 8.96 x 10(5) copies/mL. For the 5 patients with severe refractory HC, the lowest infusion dose of ADSC was 0.9 x 10(6)/kg and the highest was 1.4 x 10(6)/kg. All 5 patients were cured. The incidence of LOHC is higher after haploidentical HSCT. LOHC is positively correlated with urine BK virus. LOHC has no obvious effect on the overall PFS of patients. ADSC infusion has a good therapeutic effect on severe and prolonged LOHC.