Pineda, Alvaro A.

Abstract Therapeutic apheresis (TA) provides the means for the removal of blood components that are abnormal or that circulate in excessive amounts and have a defined pathogenetic role, or are thought to have one. Multiple disease processes have been treated with TA at one time or another, but scientific assessment of the therapeutic effects of the procedure has lagged behind application of the technology. This led the American Medical Association and the American Society for Apheresis to publish position papers on the proper applications of TA. In the field of oncology, therapeutic plasma exchange (TPE) and related procedures may be the treatment of choice for some conditions (e.g., TPE for thrombotic thrombocytopenic purpura, therapeutic leukapheresis for extreme leukocytosis in acute myelogenous leukemia, etc.), or may represent a promising therapeutic modality whose efficacy needs to be established by randomized controlled trials in the future (e.g., photopheresis for the treatment of cutaneous graft-versus-host disease). Some applications should be considered strictly investigational, and should be offered to patients only if they are part of an approved research protocol (e.g., extracorporeal immunoadsorption with staphylococcal protein A for non-hematologic cancer). Routine use of TA should be restricted to conditions where the benefit has been established by controlled studies or the best available evidence.

Abstract Peripheral blood infused total autograft absolute lymphocyte count (A-ALC) correlates with day 15 absolute lymphocyte count and is an independent prognostic factor for survival after autologous stem cell transplantation (ASCT) for non-Hodgkin lymphoma (NHL). Factors to enhance A-ALC collections are not well defined. We hypothesize that the number of peripheral blood apheresis collections (PBAC) directly correlates with A-ALC. 190 consecutive NHL patients who underwent ASCT at the Mayo Clinic between 1993 and 2001 were analyzed. The primary end point of the study was to assess the correlation between the number of PBAC and A-ALC. The secondary end point was to determine if the number of PBAC affected survival post-ASCT. Of the 190 patients, 18 patients underwent 1 PBAC, 23 patients 2 PBAC, 50 patients 3 PBAC, 37 patients 4 PBAC, 50 patients 5 PBAC, and 12 patients had ≥ 6 PBAC. There was no association between the number of PBAC and the number of CD34+ stem cells collected (p= 0.25). A strong association between number of PBAC and A-ALC (Kruskall Wallis test, p <0.0001)(Figure 1) was identified. Using a cut-off of 4 PBAC, superior overall survival (OS) and progression-free survival (PFS) were observed for patients that underwent 4 PBAC or more compared to patients that underwent less than 4 PBAC (86 months vs 18 months, p <0.0001; 76 months vs 10 months, p <0.0001, respectively). Multivariate analysis demonstrated PBAC ≥ 4 is an independent prognostic factor for OS (RR = 0.654, 95%CI: 0.529–0.804, p< 0.0001) and for PFS (RR = 0.682, 95%CI: 0.561–0.826, p< 0.0001) when compared with other significant factors including performance status, lactate dehydrogenase and extra nodal disease. These data suggest that increasing the number of PBAC beyond the minimum number required to meet CD34+ collection targets may result in improved overall and progression-free survival mediated by an increase in autograft absolute lymphocyte count.

Patients with severe, inoperable cholestasis and intractable pruritus not responding to conventional medical therapy might benefit from a depletion of their bile acid pool by sorbent perfusion since accumulated bile acids are possibly responsible for their itching. In vitro, USP-charcoal-coated glass beads removed bile acids from human plasma far better than any other sorbent tested. In order to demonstrate the safety and efficacy of charcoal plasmaperfusion in vivo, five dogs underwent plasmapheresis one week following cholecystectomy and bile duct ligation, and 2.2 ± 0.2 (x̄ ± SD) times their plasma volume was passed over a column containing 400 ml of charcoal-coated glass beads prior to reinfusion. During the procedure the plasma bile acid concentration was reduced by 40.2 ± 4.0% and the bilirubin level by 48.2 ± 3.3%. The columns, whose capacity was far from being saturated, retained 1.3 ± 0.4 times the pre-perfusion plasma pool of bile acids (1.1 ± 0.2 for bilirubin) suggesting that substantial amounts of bile acids and bilirubin were mobilized from tissue stores. The procedure was well tolerated by the animals and might have promising clinical applications.