Porrata, Luis F.

Abstract Absolute lymphocyte count (ALC) recovery post-autologous stem cell transplantation has been documented as an independent predictor for survival in non-Hodgkin lymphoma. The effect of ALC recovery on survival during standard CHOP or R-CHOP chemotherapy for newly diagnosed diffuse large B cell lymphoma (DLBCL) is unknown. To participate in the study, patients required to receive their full treatment with complete blood count determinations at the Mayo Clinic College of Medicine. Of 1633 DLBCL cases seen at the Mayo Clinic College of Medicine between February 1994 through August 2004, 212 consecutive DLBCL patients were eligible for the study. We study ALC recovery as a prognostic factor for progression-free survival (PFS) and overall survival (OS) in DLBCL patients treated with at least 3 cycles of CHOP or R-CHOP. 57% were male and the median age was 66 years (range: 20 – 87); 42% had elevated LDH, only 11% had a PS of 2 or higher; 58% were low stage (I or II); 88% of pts achieved a complete response. ALC was evaluated at the beginning of each treatment cycle, focusing on cycles 1–3 and the 3 month post treatment sample. ALC for each of the cycles were significantly correlated with PFS and OS, with cycle 1 ALC most significantly correlated when accounting for inherent differences based on treatment (Rx) type (i.e. CHOP vs. R-CHOP) as well as high vs. low IPI (PFS: p = 0.0012; OS: p = 0.005). Also, 74 pts achieved an ALC of at least 1,000 during all three cycles, where there was no significant relationship with this incidence and Rx type; this incidence was significantly associated with higher PFS (p = 0.0007) and OS (p = 0.0006), even when accounting for Rx type and high vs. low IPI. In the 179 pts who had 3-month post-Rx ALC data, this was also significantly associated with PFS (p = 0.002) and OS (p = 0.0009), while still accounting for Rx type and IPI status. Achievement of ALC >= 1,000 post-Rx was also significant for PFS (p = 0.0014) and OS (0.003). Also of note, only cycle 1 ALC was significantly different in high vs. low IPI pts (p = 0.008). In summary, these data support the hypothesis that there is a critical role of lymphocyte (immune) recovery during CHOP/R-CHOP chemotherapy in DLBCL.

Abstract AMD3100, a CXCR4 receptor antagonist, has been studied as a stem cell mobilization agent for the purpose of autologous stem cell transplantation (ASCT) in hematologic malignancies. Lymphocyte subset analysis of peripheral blood in patients treated with AMD3100 has been studied in healthy volunteers. To date, no reports exist describing the lymphocyte subsets of the autograft in patients undergoing AMD3100 stem cell mobilization for the purposes of ASCT in non-Hodgkin lymphoma (NHL). Considering our prior work demonstrating the significant impact of autograft lymphocyte content on clinical outcomes of patients undergoing ASCT for NHL we set out to profile autograft lymphocyte subsets of patients undergoing mobilization with AMD3100. Using flow cytometry, we analyzed aliquots of apheresis products in 7 patients with NHL undergoing AHSCT who received AMD3100 in addition to G-CSF as a part of their mobilization regimen. These results were compared to 29 patients with NHL who had undergone stem cell mobilization with G-CSF alone. There were no significant differences between these two groups of patients in terms of sex, age, performance status, histology, LDH, and number of pretransplant chemotherapeutic regimens. CD34+ cells collected at apheresis did not differ significantly between the groups. However, compared with G-CSF alone, patients that received AMD3100 had an approximate 5-fold increase in CD4+ cells (0.62 x 109 cells/kg vs. 0.12 x 109 cells/kg, p = 0.0004), a 3.5-fold increase in the absolute number of autograft CD3+ cells (1.21 x 109 cells/kg vs. 0.33 x 109 cells/kg, p = 0.0017), and a 2.5-fold increase in CD8+ cells (0.48 x 109 cells/kg vs 0.19 x 109 cells/kg, p = 0.215). A significant increase was also noted in CD4+25+ cell compartment (0.17 x 109 cells/kg vs. 0.006 x 109 cells/kg, p = 0.0001). No significant difference was noted in the absolute number of autograft CD16+56+ NK cells. Finally, an increase in the autograft total absolute lymphocyte count (41.6 x 109 cells/kg vs. 2.88 x 109 cells/kg, p < 0.001) as well as peripheral blood absolute lymphocyte count at day 15 after AHSCT was observed in those patients who had received AMD3100 (0.79 x 109 cells/kg vs. 0.58 x 109 cells/kg, p = 0.04). The increased lymphocyte content of the autograft (total and subset) would suggest the potential of positive impact on clinical outcomes in patients mobilized with AMD3100. Indeed, none of the patients who received AMD3100 had relapsed disease at one year post-transplant (although two of these patients are currently 9 months and 11 months post-transplant respectively), whereas 10 of the 29 control patients had relapsed disease at one year. Further studies are necessary to confirm these observations and ascertain their clinical significance.

Abstract Mantle-cell lymphoma (MCL) is characterized by an aggressive clinical course and poor prognosis with a median survival of only 3 to 4 years. High dose chemotherapy followed by autologous stem cell transplantation (ASCT) is an effective treatment strategy for MCL demonstrating significantly prolongs progression free survival (PFS) when compared to IFNa maintenance therapy of patients in first remission. We have previously shown that absolute lymphocyte count at day 15 (ALC-15) after ASCT is an independent prognostic factor for survival in hematologic malignancies (non-Hodgkin’s lymphoma (NHL), Hodgkin’s disease, multiple myeloma, primary amyloidosis, acute myelogenous leukemia) and breast cancer. The study of ALC-15 after ASCT as a prognosis factor in NHL included different subtypes of lymphomas. The relationship of ALC-15 after ASCT in patients with MCL has not been specifically addressed. Herein we present data evaluating the impact of early lymphocyte recovery (ALC-15) in patients undergoing ASCT for MCL. We retrospectively reviewed the medical records of 42 consecutive patients (9 females and 33 males) with MCL who underwent ASCT at the Mayo Clinic in Rochester from 1993 to 2005. Based on our previous studies, the ALC-15 threshold was set at 500 cells/μL. The median patient age at transplant was 57 years (range, 37–71) and the median follow-up after ASCT was 25 months (range, 2–106 months). The median overall (OS) and PFS times were significantly better for the 24 patients that achieved an ALC-15 ≥ 500 cells/mL compared with 18 patients with ALC-15 < 500 cells/μL (not reached versus 30 months, P < 0.01 and not reached versus 16 months, P < 0.0006, respectively). Multivariate analysis adjusting for other prognostic factors suggests that ALC-15 is an independent prognostic factor for OS and PFS. ALC-15 ≥ 500 cells/mL is associated with significantly improved clinical outcomes following ASCT in patients with MCL.

Abstract Introduction: Stem cell transplant is an increasingly widely applied technique for managing amyloidosis. As in multiple myeloma, the treatment would not be expected to be curative and patients would be expected to relapse in most instances. In addition, approximately one-third of patients fail to respond to initial therapy. The role of second transplantation in treatment failures or patients who relapse is reviewed. Patients: Of 242 patients undergoing high dose conditioning and stem cell transplantation for amyloidosis (AL) at the Mayo Clinic, 6 subsequently underwent a second transplant. Results: Patient 1, who had single organ renal amyloid nephrotic syndrome responded and relapsed at 73 months, received a second stem cell transplant achieving a hematologic complete response with normalization of a markedly elevated pre transplant free light chain (59 to 1.9 mg/dL) and is alive at 12 months. Patient 2 relapsed 42 months after transplant for single organ renal amyloidosis; the second stem cell transplant, has normalized his free light chain ratio reduced his urinary protein loss from 5450 to 1482 mg/day and he is alive 21 months following his second transplant (63 months overall). Patient 3 relapsed 34 months after a response of renal and cardiac amyloidosis. After transplant two, he failed to achieve a 50% reduction in his free light chain, began hemodialysis 7 months post transplant and died one year post transplant. Patient 4 with single organ cardiac involvement relapsed 30 months following his first transplant and died on day +5 of his second transplant of an acute pulmonary embolus. Patient 5 was a response failure after his first transplant, had a second transplant 35 months later, having failed Dexamethasone followed by Melphalan/Dexamethasone therapy, and died 3 months later of progressive disease. Patient 6 had single organ vascular involvement manifest by calf and thigh claudication and failed to respond with his first transplant with a persistently elevated free light chain. The second transplant was performed six months after the first without further free light chain reduction and persistent claudication at 11 months. Conclusion: Patients who failed to achieve a hematologic response after a first transplant appear not to benefit from a second course of high dose therapy. Among 4 patients who were previously responsive and relapsed, one achieved a hematologic complete response, one achieved a hematologic partial response, and two died. The two patients achieving a second hematologic response had the longest response duration (73 and 42 months) following their first transplant, and the second response presumably reflects favorable (indolent; non proliferative) biology of the underlying plasma cell dyscrasia. High dose therapy and stem cell transplant may be an effective salvage regimen for patients who responded to a first transplant and whose response lasted greater than 36 months.

Abstract Background: Overall prognosis in CMML is unfavorable. The only curative option is ASCT, yet the limited data available from the largest reported series, reports 2 year overall (OS) and disease free (DFS) survival of only 21% and 18%, respectively [Kroger et al, BJH 2002, 118: 67]. Data on DLI for CMML are generally restricted to case reports. We retrospectively reviewed our experience of ASCT and DLI for adults with CMML. Patients: Seventeen consecutive patients (11 males) with CMML underwent ASCT from 1992 to 2004. At transplant, median (range) age was 50 years (26–60), duration of disease 7 months (2.5–44), and bone marrow (BM) blast count 6% (1–58%). Prior to transplant, 11 had evolved into acute myeloid leukemia (AML). Of these, 10 received standard induction chemotherapy but only one achieved complete remission (CR); 5 had persistent CMML and 4 refractory AML. Karyotype at transplant was either normal (n=9) or revealed isolated monosomy 7 (n=4), complex (n=1), or single, nonrecurrent abnormalities. ASCT: Conditioning was Cytoxan/Total Body Irradiation in all but one who received a non-myeloablative (NMA) regimen (cladrabine/ATG/thiotepa). Stem cell source was HLA-identical sibling in 14 patients and unrelated in 3 peripheral blood (PB) in 7, BM in 8, or both in 2. Median BM mononuclear cell/kg dose was 2.3 (1.7–4.15) x 108 and PB CD34 cell/kg was 5.12 (0.94–7.29) x 106. Graft versus host disease (GVHD) prophylaxis was cyclosporin alone (n=3), with methotrexate (n=12), or prednisone (n=1) or was tacrolimus/methotrexate (n=1). Post-transplant course: All but one patient who died on day 11 of sepsis engrafted (sustained ANC > 500) at a median of 19.5 days (13–31). CR was documented in 13 (76%) post-ASCT. Acute GVHD was grade II-IV (75%) and III-IV (37.5%) and chronic GVHD was extensive (n=37.5%). Seven (41%) demonstrated relapse or persistent disease at a median of 6 months (3–55.5) and 13 (76%) have died due to disease (n=6) or transplant related mortality (n=7). DLI: Six patients underwent DLI for morphologic (4 recurrent/persistent CMML, 1 early AML with extramedullary disease) or cytogenetic relapse (n=1), at a median of 19.5 days (6–52) post-relapse. Median BM blast count at DLI was 3% (1–22%). The median CD3+ cell dose infused was 30.45 x 107 cells/kg (11.2–45.5), given in a median of 3 infusions (range: 1–3). Four did not respond, but two (one with cytogenetic and one with morphologic relapse) achieved a durable CR of 15 months each, both had extensive CGVHD, from which one died of complications. The other relapsed but failed to respond to a second DLI and died of disease. Survival: For the entire cohort, median DFS and OS were 6 months and 7 months, respectively. At last follow up, 4 remain alive, 3 in continuous CR (18%), at 12, 29 (treated with the NMA regimen) and 116 months, respectively. Of the 3 patients surviving in remission, all had transformed to AML prior to ASCT and only one had achieved CR following induction chemotherapy. Multivariate analysis failed to demonstrate any significant effect of age, duration of disease, BM blast %, karyotype or induction chemotherapy on RFS or OS, likely reflecting the small numbers available for analysis. Conclusion: The current study demonstrates anti-CMML activity of both ASCT and DLI although overall outcome is less than encouraging and unpredictable. Novel approaches are needed.

Abstract Intravascular lymphoma is a rare subtype of extranodal DLBCL characterized by the proliferation of malignant B-cells within the lumina of blood vessels. Organ involvement is variable and diffuse. Making the diagnosis can be challenging with symptoms persisting for months prior to definitive diagnosis. Treatment to date with standard anthracycline containing chemotherapy regimens has been disappointing with variable response rates, high relapse rates, and median survival times typically measured in months. We report diagnostic, treatment, and follow-up information regarding a group of patients with intravascular lymphoma evaluated at the Mayo Clinic with special attention to those receiving rituximab and/or high dose chemotherapy with or without peripheral blood autologous stem cell rescue. Methods: The medical records of patients with intravascular lymphoma seen at the Mayo Clinic between January 1970 and May 2005 were reviewed. Patients were included if they had evidence of intravascular lymphoma at the time of diagnosis of lymphoma. Pathologic specimens were reviewed for confirmation of diagnosis. Results: Twenty patients with a diagnosis of intravascular lymphoma were identified. Their median age was 66.5 years. Thirteen (65%) had B symptoms at the time of diagnosis and 13 had a performance status ≥ 3. Nine (45%) had an IPI ≥ 4. The median time to diagnosis from the onset of symptoms was 5.5 months. All had stage IV disease with biopsy proven involvement of at least one organ. The sites of disease involvement were CNS (10), marrow (7), lung (5), adrenal (3), kidney (2), lymph node, seminal vesicle, and skin (1). Two patients had involvement of three organs, six had involvement of two organs, and twelve had involvement of one organ. Nineteen patients received chemotherapy: ProMACE/CytaBOM (3), CHOP (6), RCHOP (6), DHAP (1), high dose methotrexate (1), methylprednisolone, nitrogen mustard, rituximab (1), and hyperCVAD (1). Three patients underwent peripheral blood autologous stem cell rescue after conditioning with BEAM. With a median follow-up of 60 months for all patients, the median overall survival was 8 months. No difference in outcome was seen with regard to site of organ involvement, number of organs involved, presence of B symptoms, or IPI. With a median follow-up for those receiving rituximab of 26 months, the median survival has not yet been reached while the median survival for those receiving non-rituximab containing regimens was 6.5 months. Similarly, with a median follow-up for those receiving high dose chemotherapy (hyperCVAD or BEAM) of 9.3 months, the median survival has not yet been reached while the median survival for those not receiving high dose therapy was 7 months. Conclusion: Intravascular lymphoma is a unique and aggressive subtype of DLBCL. The clinical presentation and sites of organ involvement are variable and the time from onset of symptoms to diagnosis can be prolonged. Standard chemotherapeutic treatment leads to poor outcomes. However, survival may be improved upon with newer strategies such as the use of rituximab and/or high dose chemotherapy with or without peripheral blood autologous stem cell rescue.

Abstract The proposed immune-mediated mechanisms of action of Rituximab (ADCC or “vaccinal” effect) suggest that the efficacy of rituximab therapy depends on the immunocompetency of the host. Therapies, such as IL-12, that stimulate the immune system may increase the efficacy of rituximab. Recently, we reported that absolute lymphocyte count (ALC), as a surrogate maker of immune recovery, is a survival prognostic factor in autologous stem cell transplantation for non-Hodgkin’s lymphoma (NHL). We hypothesize host immune competence (i.e, normal ALC counts) would predict a superior survival in NHL patients treated with rituximab-based regimens. The primary end-point of the study was to assess whether the ALC count prior to rituximab therapy predicted progression-free survival (PFS) and the second end-point was to identify which lymphocyte subset was responsible for affecting PFS. We studied 41 NHL patients that participated in our Phase I interleukin-12 plus rituximab study. These patients were selected because the Phase I study required baseline ALC count and flow cytometry analysis providing lymphocyte subset data prior to treatment. There were 20 females and 21 males in the study. The median age of the cohort was 53 years (range: 34–84). PFS was assessed from the initial date of treatment. The median follow-up was 42 months (1–84 months). Patients with an ALC ≥ 0.9 × 109/l experienced a superior PFS versus an ALC < 0.9 × 109/l prior to rituximab therapy (31 months vs 4 months, p < 0.0001). The relapse rate in the ALC ≥ 0.9 × 109/l group was 55% (11/20) versus 95 % (20/21) in the ALC < 0.9 × 109/l (p < 0.0016). Patients with a CD4 count ≥ 500 cells/μl also experienced a superior PFS versus a CD4 count < 500 cells/μl (21 months vs 9 months, p < 0.0062). The relapse rate in the CD4 count ≥ 500 cells/μl group was 56% (9/16) versus 88 % (22/25) in the CD4 count < 500 cells/μl (p < 0.0216). No association with PFS was identified for CD3, CD8, CD19, CD16/56, the use of IL-12, or lymphoma type by WHO classification. CD4 count was found to be an independent prognostic factor for PFS. In the subgroup of patients with follicular lymphoma, patients with an ALC ≥ 0.9 × 109/l experienced a superior PFS versus an ALC < 0.9 × 109/l prior to rituximab therapy (35 months vs 9 months, p < 0.0076). The relapse rate in the ALC ≥ 0.9 × 109/l group was 45% (5/11) versus 90 % (9/10) in the ALC < 0.9 × 109/l (p < 0.0243). Patients with a CD4 count ≥ 500 cells/μl also experienced superior PFS versus a CD4 count < 500 cells/μl (not reached vs 9 months, p < 0.0098). The relapse rate in the CD4 count ≥ 500 cells/μl group was 29% (2/7) versus 86 % (12/14) in the group with a CD4 count < 500 cells/μl (p < 0.0216). CD4 count was found to be an independent prognostic factor for PFS when compared to the Follicular Lymphoma International Prognostic Index at the time of treatment. Our data suggest the significance of an immunocompetent host in predicting the efficacy of rituximab therapy. These data support our previous report that patients with higher number of activated CD4+ cells at the lymphoma site have a better prognosis (Ansell et al, JCO2001; 19: 720–6). These findings warrant further studies to understand the role of ALC (i.e, CD4 count) in the mechanism of action of rituximab. Supported in part by CA69912

Abstract We previously have reported that autograft absolute lymphocyte count (A-ALC) is a possible prognostic factor for survival after autologous peripheral blood stem cell transplant (ASCT) for myeloma (MM). Factors affecting A-ALC in MM are unknown. We hypothesize that method of stem cell mobilization, hematopoietic growth factor (HGF) vs. HGF+Cytoxan chemotherapy (C+HGF), directly affects A-ALC collection. 191 consecutive MM patients between 1994 and 2004 were analyzed retrospectively. Patients generally were mobilized with C+HGF prior to 2003. Thereafter, C+HGF was reserved largely for those with ≥4% circulating peripheral blood plasma cells (PC), a negative prognostic indicator. No patients were transplanted in disease relapse or refractory disease. Patients also were matched for age, sex, β2-microglobulin, conventional cytogenetics, LDH, c-reactive protein, number of prior therapies, plasma cell labeling index (PCLI), pre-mobilization ALC, and % bone marrow (BM) PC. The groups HGF (n=80) and C+HGF (n=111) differed with respect to the conditioning regimen (p < 0.0001), and presence of (≥4%) circulating peripheral blood PC (p<0.005). The primary end-point of the study was to assess the correlation between HGF vs C+HGF, and A-ALC. The secondary endpoint was to determine if HGF vs C+HGF affected survival post-ASCT. Patients mobilized with HGF had a higher A-ALC compared to those mobilized with C+HGF [0.764 x 109 lymphocytes/kg (range: 0.146–1.803) vs. 0.212 (range: 0.016–1.26), p<0.0001]. No association was identified between A-ALC and conditioning regimens (p = 0.19) and PC (p = 0.31). Median overall survival (OS) and progression-free survival (PFS) were longer in those mobilized with HGF vs. C+HGF (not reached vs. 48 months, p<0.0150; not reached vs. 21 months, p<0.007, respectively). Multivariate analysis demonstrated that age ≥50 vs age ≤50 (p<0.05) and A-ALC ≥0.5 vs <0.5x109 lymphocytes/kg (p<0.0397) were independent predictors of OS. Factors influencing PFS in the multivariate analysis included circulating PC ≥4% vs <4% (p<0.0157), PCLI ≥ 1% vs PCLI ≤ 1% (p<0.0107), and A-ALC ≥0.5 vs <0.5x109 lymphocytes/kg (p<0.0042). On multivariate analysis, the method of stem cell mobilization and the conditioning regimen did not have a statistically significant effect on either OS or PFS. We hypothesize that the differences in PFS and OS seen between the HGF vs C+HGF mobilization groups are mediated through the A-ALC. These data suggest that mobilization regimens should not only collect CD34+ stem cells, but also be optimized to collect an A-ALC target which may impact on PFS and OS post-ASCT.

Abstract Introduction: We previously reported that serum cardiac biomarkers are among the most powerful predictors of overall survival. This observation was based on outcomes of more than 300 patients with primary systemic amyloidosis (AL) receiving either low dose chemotherapy or high dose chemotherapy with peripheral blood stem cell transplant (PBSCT). Not all institutions use the N-terminal pro-brain natriuretic peptide (NTproBNP) assay, but rather the B-type natriuretic peptide (BNP) assay. We therefore determined the relative utility of BNP in patients with AL undergoing PBSCT and up-dated our results using our NTproBNP-troponin T staging system. Methods: Between 4/10/96 and 2/24/05, 164 patients with AL undergoing PBSCT had measurements of serum cardiac biomarkers. All BNP measurements were done on fresh serum (Biosite Inc., San Diego). The NTproBNP (Roche Diagnostics, Indianapolis, IN) and troponin T (TnT) (Roche Diagnostics, Indianapolis, IN) measurements were done on either stored serum or on fresh samples as previously reported. Follow-up for patients was through March 2005. Results: Between 5/1/03 and 2/15/05, 72 patients had BNP measurements pre-transplant. The median value was 167 pg/ml (range 5 to 7739). Forty-two of these patients also had an NTproBNP measured. There was good agreement between the two tests in the 42 patients that had both measurements (rho 0.823, p<0.0001). To further test the relationship between the two tests, we evaluated the correlation between BNP and NTproBNP using 204 simultaneous measurements from 106 patients (rho=0.89, p<0.0001). Next, we tested the prognostic utility of BNP. Using a cut-off point of 120 pg/L (the upper limit of normal for women over the age of 70 and the 50th percentile of all measurements in our data set), we found that BNP was prognostic for survival post-transplant. It was independent of TnT values, and patients could be divided into 3 risk categories using these two measurements (low risk if both values were low, high-risk if both were high, and intermediate if either was high). This system was highly predictive of overall survival (Figure A). We next compared the BNP-TnT staging system to our previously reported NTproBNP-TnT staging system in the 42 patients that had all 3 values pre-transplant. The correlation between the two staging systems was excellent (rho=0.91, p<0.0001). Follow-up for the 100 patients who had been reported previously is now 26.9 months. As shown in Figure B, the NTproBNP-TnT system predicts for overall survival post transplant. Conclusions: Serum levels of cardiac biomarkers are invaluable prognostic markers in patients with AL. Preliminary data would suggest that a BNP-TnT system is as useful as the NTproBNP-TnT system. Risk thresholds: BNP <120 pg/ml; TnT <0.035 ng/ml; NT-proBNP < 332 pg/ml BNP-TnT statisfaction: low risk, both low; high risk, both high; intermediate, either high. NT-proBNP-TnT satisfaction: low risk, both low; high risk, both high; intermediate, either high. Risk thresholds: BNP <120 pg/ml; TnT <0.035 ng/ml; NT-proBNP < 332 pg/ml BNP-TnT statisfaction: low risk, both low; high risk, both high; intermediate, either high. NT-proBNP-TnT satisfaction: low risk, both low; high risk, both high; intermediate, either high.

Abstract Introduction: The Bone Marrow Transplant Program at Mayo Clinic (Rochester, Minnesota) developed a multidisciplinary approach (involving physicians, nurses, pharmacists, dietitians, and financial specialists) for outpatient management of patients undergoing stem cell transplantation. This approach uses an electronic ordering system for diagnostic tests and chemotherapy to minimize medical errors. Table. Patient Characteristics (N=716) Characteristic Value Male, no. of patients (%) 426 (59) Age, median (IQR), y 59 (53–65) Creatinine, median (IQR), mg/dL 1.0 (0.9–1.2) b2-Microglobulin, median (IQR), mcg/mL 2.5 (1.9–3.7) Gammopathies, no. of patients (%) Measured by serum immunofixation or immunoelectrophoresis IgA 148 (21) IgG 414 (58) IgM 6 (1) IgD 12 (2) Light chain 83 (12) Biclonal 6 (1) None 47 (7) Measured by urine immunofixation or immunoelectrophoresis k light chain 402 (56) l light chain 226 (32) Biclonal 1 (0) None 79 (11) Not performed (anuric) 8 (1) Status at stem cell transplant, no. of patients (%) Untreated 4 (1) Plateau 436 (61) Primary refractory 113 (16) Relapse after therapy 93 (13) Relapse during therapy 70 (10) Characteristic Value CD34+ cells, median (IQR), ×106/kg Collected, no. 10.0 (7.6–12.6) Infused, no. 4.7 (3.9–6.2) Sessions of apheresis, median (IQR) 3 (2–5) Engraftment, median (IQR), days after transplantation Neutrophils, 0.5×109/L 13 (12–15) Platelets, 50×109/L 16 (14–22) Duration of hospitalization, median (IQR), d 4 (0–10) Abbreviation: IQR, interquartile range. Results: During a 45-month period after implementation of the program (2005-Sept 2007), the day-100 survival rate was 99.5% for low-risk myeloma patients (transplantation during first plateau; n=202) and 97% for high-risk myeloma patients (refractory, relapsing or second or greater plateau; n=71). The overall day-100 survival rate was 99%(270/273). Analysis of hospitalization trends since inception of the program showed that 39% of patients completed the transplant procedure as outpatients. The median duration of hospitalization for all patients was 4 days; age and serum creatinine levels were predictive of the need for and duration of hospitalization Conclusion: Outpatient stem cell transplantation is feasible for patients with multiple myeloma with a therapy mortality of 1%. Nearly 40% of our patients completed the procedure without hospitalization. Age and serum creatinine levels predicted a higher likelihood of hospitalization. Implementation of out patient transplant requires affordable housing in the community since many third party payers do not support hotel costs despite the reduction of hospital days. The hospital physical plant and patient registration process has to support use of designated hospital rooms for purely out patient practice. The transplant team must have process owners to standardize across all disease categories collection protocols, conditioning regimens, infusion SOP’s and post infusion supportive care guidelines for standard antibiotics, narcotics, laboratory work and transfusion thresholds. A care team meeting between physicians, nursing, dietary, pharmacy, business office, data base and appointment coordinators is essential to coordinate all the multidisciplinary efforts. Kaplan-Meier curve shows the percentage of patients remaining in the hospital through time t, stratified on the basis of age greater than or less than or equal to 65 years Kaplan-Meier curve shows the percentage of patients remaining in the hospital through time t, stratified on the basis of age greater than or less than or equal to 65 years Kaplan-Meier curve shows the percentage of patients remaining in the hospital through time t, stratified on the basis of creatinine greater than or equal to or less than 1.5mg/dL Kaplan-Meier curve shows the percentage of patients remaining in the hospital through time t, stratified on the basis of creatinine greater than or equal to or less than 1.5mg/dL