Stem cell mobilization in HIV seropositive patients with lymphoma

High-dose chemotherapy with autologous peripheral blood stem cell rescue has been reported as feasible and effective in HIV-associated lymphoma. Although a sufficient number of stem cells seems achievable in most patients, there are cases of stem cell harvest failure. The aim of this study was to describe the mobilization policies used in HIV-associated lymphoma, evaluate the failure rate and identify factors influencing mobilization results. We analyzed 155 patients who underwent attempted stem cell mobilization at 10 European centers from 2000–2012. One hundred and twenty patients had non-Hodgkin lymphoma and 35 Hodgkin lymphoma; 31% had complete remission, 57% chemosensitive disease, 10% refractory disease, 2% untested relapse. Patients were mobilized with chemotherapy + G-CSF (86%) or G-CSF alone (14%); 73% of patients collected >2 and 48% >5 × 106 CD34+ cells/kg. Low CD4+ count and refractory disease were associated with mobilization failure. Low CD4+ count, low platelet count and mobilization with G-CSF correlated with lower probability to achieve >5 × 106 CD34+ cells/kg, whereas cyclophosphamide ≥3 g/m2 + G-CSF predicted higher collections. Circulating CD34+ cells and CD34/WBC ratio were strongly associated with collection result. HIV infection alone should not preclude an attempt to obtain stem cells in candidates for autologous transplant as the results are comparable to the HIV-negative population.