Peripheral blood progenitor cell mobilization in patients with primary refractory lymphoma or at first relapse: comparison with patients at diagnosis and impact on clinical outcome

DHAP plus filgrastim as an effective peripheral stem cell mobilization regimen for autologous stem-cell transplantation in patients with relapsed/refractory lymphoma: A single center experience

This study aimed to evaluate the efficiency of DHAP regimen plus filgrastim for mobilization of stem cells in patients with recurrent and/or refractory lymphoma. Thirty-four patients who took DHAP as salvage therapy prior to autologous stem cell transplantation were included. After chemotherapies, 2 cycles of DHAP plus filgrastim were administered to the patients. Stem cells from 32 patients (94%) were collected on median 11th day (8-12), and the median collected CD34(+) cell dose was 9.7 × 10(6)/kg (range 3.8-41.6). DHAP plus filgrastim was found to be an effective chemotherapy regimen in mobilizing CD34(+) stem cells into the peripheral.

Successful mobilization of peripheral blood stem cells with the DHAP regimen (dexamethasone, cytarabine, cisplatinum) plus granulocyte colony-stimulating factor in patients with relapsed Hodgkin's disease

High-dose chemotherapy followed by autologous stem cell transplantation can improve the outcome of relapsed and refractory Hodgkin's disease (HD) patients. The objective of the trial was to determine the mobilizing potential of the DHAP salvage regimen (dexamethasone, cytarabine, cisplatin) for the collection of peripheral blood stem cells (PBSC) in patients with relapsed HD. The target yield of harvesting CD34 + cells was > or =2 x 10(6)/kg in order to support the subsequent myeloablative chemotherapy. Most of the 105 patients included were intensively pre-treated with different combination chemotherapy regimens prior to mobilization. The use of DHAP followed by granulocyte colony-stimulating factor (G-CSF; 10 microg/kg) resulted in the successful collection of adequate numbers of PBSC in 97.1% of patients (102 of 105) with a median harvest of CD34+ cells of 13 x 10(6)/kg (range 2.6 - 85.1). More than 2.0 x 10(6) CD34+ cells/kg were achieved in 65 of 103 (63%) patients after 1 apheresis, the maximum number of aphereses for all patients was 3. It was found that the optimal time of PBSC harvest was at days 13 - 16 after initiating the mobilization regimen. These results demonstrate that the salvage chemotherapy regimen, such as DHAP combined with G-CSF, can be successfully used to mobilize PBSC in HD patients.

Comparison of peripheral blood progenitor cell yield from standard chemotherapy used in the treatment of lymphoid malignancies and high-dose cyclophosphamide: a retrospective review of 141 patients

BACKGROUND

Peripheral blood progenitor cells (PBPCs) are often collected after mobilization with high-dose cyclophosphamide (HDC) combined with growth factors. HDC may not be needed for PBPC mobilization, and patients with lymphoid malignancies can be harvested with treatment regimens of chemotherapy.

STUDY DESIGN AND METHODS

A retrospective analysis was performed on 141 patients with lymphoma or multiple myeloma whose PBPCs were harvested after chemotherapy. The PBPC yield and time to mobilization was compared between patients who received HDC (n = 51) and other chemotherapy regimens (n = 90) including high-dose cyclophosphamide and etoposide (HDC plus VP-16; n = 41), CHOP, ESHAP, ABVD, VAD, and others (n = 49). A multiple linear regression model and proportional hazards model determined factors influencing yield and time to mobilization, respectively.

RESULTS

The difference in mean yield between HDC and all non-HDC regimens was significant, with HDC plus VP-16 resulting in the highest yields. The proportion of patients achieving a CD34 count in excess of 5 x 10(6) per kg did not differ significantly between the regimens. In a multiple linear regression model, HDC plus VP-16 resulted in a higher PBPC yield than HDC but all other regimens did not. In addition, patients exposed to more than one prior chemotherapy regimen had lower yield regardless of the mobilization regimen. The mean number of days to mobilization with HDC was 10.2 days, 17.1 days for HDC plus VP-16, and 14.2 days for all other regimens. The timing of mobilization was influenced by the chemotherapy used and the number of prior regimens in a proportional hazards model.

CONCLUSION

These results demonstrate a higher mean yield of PBPCs with HDC plus VP-16 but no difference in yield between non-HDC plus VP-16 regimens used for first-line or relapse therapy and HDC, suggesting that HDC may be an unnecessary additional therapy.

The role of diagnosis in patients failing peripheral blood progenitor cell mobilization

BACKGROUND

Failure to mobilize PBPCs for auto-logous transplantation has mostly been attributed to previous therapy and poses therapeutic problems.

STUDY DESIGN AND METHODS

The role of underlying disease was analyzed in 17 of 73 (23%) patients with PBPC mobilization failure, and secondary mobilization with high-dose filgrastim was attempted.

RESULTS

Of 16 patients with acute leukemia, 13 (81%) mobilized poorly. In contrast, of 57 patients with non-Hodgkin's lymphoma, Hodgkin's lymphoma, multiple myeloma, and solid tumor, 53 (93%, p < 0.001) showed good PBPC mobilization. Relapsed disease did not predispose to poor mobilization. As secondary mobilization attempt, 7 patients received 25 micro g per kg per day filgrastim without chemotherapy leading to a 3.7 +/- 2.8-fold (SD) increase in the maximum number of circulating CD34+ cells (p = 0.104). PBPC apheresis yielded 3.3 (+/-0.5) x 10(6) CD34+ cells per kg of body weight in 5 patients. Four poor mobilizers received 50 micro g per kg per day filgrastim as second or third mobilization attempt. Circulating CD34+ cells in these patients increased by 1.5 (+/-0.7) compared with the primary G-CSF application.

CONCLUSION

Selective PBPC mobilization failure was seen in patients with acute leukemia whereas remarkably good mobilization was seen in other malignancies. Increasing the filgrastim dose to 25 micro g per kg per day may allow PBPC collection in patients failing PBPC mobilization.

High-dose ara-C with autologous peripheral blood progenitor cell support induces a marked progenitor cell mobilization: an indication for patients at risk for low mobilization

A high-dose (HD) chemotherapy scheme was designed for the collection of large numbers of peripheral blood progenitor cells (PBPC) in lymphoma patients who were candidates for myeloablative therapy with autograft. The scheme included the sequential administration of HD cyclophosphamide (CY) (7 g/m(2)) and HD ara-C (2 g/m(2) twice a day for 6 consecutive days), followed by final consolidation with PBPC autograft. PBPC harvests were scheduled following both HD CY and HD ara-C. To minimize hematologic toxicity, small aliquots of PBPC (<or=3 x 10(6) CD34(+) cells/kg) collected following HD CY were reinfused following HD ara-C. The treatment was delivered to 112 patients (median age: 43 years) with lymphoid malignancies (107 non-Hodgkin's lymphoma, four Hodgkin's lymphoma, one amyloidosis); 75 patients were at disease onset, whereas 37 had relapsed or were refractory after first-line conventional therapy. PBPC mobilization was assessed in terms of peak values of circulating CD34(+) cells/microl, as well as total CD34(+) cells/kg collected. In a few patients CFU-GM/kg were also evaluated. At the time of maximal mobilization following HD CY, 93 'high-mobilizer' patients had >20 circulating CD34(+) cells/microl, whereas the remaining 19 'low-mobilizer' patients did not reach this cut-off value. In spite of poor mobilization after HD CY, 16 out of 19 low mobilizers provided good harvests following HD ara-C; overall, median collected CD34(+) cells x 10(6)/kg were 1.4 (0-3.1) and 10.2 (0-37) after HD CY and HD ara-C, respectively (P = 0.00007). Similar patterns were observed when PBPC were evaluated by CFU-GM/kg. Complete and durable hemopoietic reconstitution followed autograft with post HD ara-C PBPC. Within the high-mobilizer group, 88 patients received HD ara-C and 79 (90%) still showed high mobilization; overall, median collected CD34(+)cells x 10(6)/kg were 17.8 (range 3-94) and 19 (range 0-107) after HD CY and HD ara-C respectively (P = NS). Thus, the scheme allowed sufficient PBPC collections for autografting in low mobilizer patients; in addition, the scheme could be considered whenever extensive chemotherapy debulking is needed prior to PBPC collection.

The CD19+ B-cell counts at peripheral blood stem cell mobilization determine different levels of tumour contamination and autograft purgability in low-grade lymphoma

The tumour load of peripheral blood stem cell (PBSC) harvests and the outcome of ex vivo immunomagnetic B-cell purging was investigated in 19 patients with low-grade lymphoma. To quantify the tumour load, we combined fluorescence-activated cell sorting measurement of CD19+ B-cells and determination of the B-cell light chain ratio (LCR) with consensus complementarity-determining region III-polymerase chain reaction (CDRIII-PCR) and gene scan analysis. The number of tumour cells was calculated using B-cell extracts from the PBSCs. Two different patterns were distinguished. In eight patients (42%) with CD19+ B cells >1% in the apheresis product, a high tumour load was found, characterized by a monoclonal LCR, positive PCR in seven out of eight cases, >5 x 10(7) extracted lymphoma cells in six out of seven PCR-assessable cases, and the presence of residual lymphoma after purging in six of seven cases. In 11 patients (58%) with <1% CD19+ B-cells in the product, a low tumour load was indicated by a polyclonal LCR, positive PCR in only 4 out of 11 cases, >5 x 10(7) extracted lymphoma cells in zero out of four PCR-assessable cases, and the presence of residual lymphoma after purging in zero out of four of these cases. The level of residual lymphoma following purging largely depended on the level of tumour contamination. CD19+ B-cells >50/microl in the peripheral blood at mobilization predicted a high tumour load in the apheresis product.

Mobilization of peripheral blood stem cells with high-dose cyclophosphamide or the DHAP regimen plus G-CSF in non-Hodgkin's lymphoma

Our study analyzes the mobilization of hematopoietic stem cells after two chemotherapeutic regimens in non-Hodgkin's lymphoma (NHL) patients. The study included 72 patients with NHL (42 follicular and 30 large cells). The mean age was 37 years (range 17-60). Sixty-four patients (88.9%) had stage III-IV disease. Forty-eight patients (66.7%) had bone marrow involvement. Systemic B symptoms were present in 42 patients (58.3%). Mobilization chemotherapy regimens were randomly assigned as DHAP in 38 patients (52.7%) or cyclophosphamide (CPM) (5 g/m(2)) in 34 (47.2%) and the results of 132 procedures were analyzed. At the time of PBSC mobilization, 46 patients (63.9%) were considered to be responsive (complete remission, partial remission or sensitive relapse) and 26 (36.1%) not responsive (refractory relapse or refractory to therapy). Pre-apheresis CD34+ blood cell count and number of previous chemotherapy treatments were used to predict the total number of CD34+ cells in the apheresis product. The mobilizing regimens (CPM or DHAP) were similar in achieving the threshold CD34+ cell yield, for optimal engraftment. Since DHAP was very effective as salvage treatment, we suggest using DHAP as a mobilizing regimen in patients with active residual lymphoma at the time of stem cell collection.

Hemopoietic progenitor cell mobilization and harvest following an intensive chemotherapy debulking in indolent lymphoma patients

An in vivo purging with intensive debulking chemotherapy prior to peripheral blood progenitor cell (PBPC) collection may reduce the risk of tumor contamination of the harvest products; however, it is usually associated with a marked reduction in PBPC mobilization. These issues have been considered while designing an adapted version of the high-dose sequential regimen for patients with lymphoid malignancies and bone marrow involvement. To reduce tumor contamination risks, PBPC collection was postponed to the end of the high-dose phase; however, in order to enhance progenitor cell mobilization, a chemotherapy-free lag period was introduced prior to the final mobilizing course. Thirty-nine patients (median age 47 years, range 26-62) with previously untreated indolent lymphoma entered this pilot study; all had advanced-stage disease, and 29 had overt marrow involvement. Sufficient numbers of PBPC to perform autograft with safety were harvested in 34 patients, with a median of 3 (range 2-5) leukaphereses. A median of 14.8 x 10(6) (range 2-51) CD34+/kg and 32.6 x 10(4) (range 1.77-250) colony forming units-granulocyte/macrophage/kg were collected per patient. In univariate analysis, the duration of the chemotherapy-free interval prior to the final mobilizing course, i.e. > or <65 days, was the most significant variable influencing progenitor mobilization. These data suggest that extensive in vivo tumor debulking is feasible provided that a sufficient chemotherapy-free period preceding the mobilizing course is allowed in order to allow a full recovery of marrow functions.