Doug Stewart

Randomized Trial of High-Dose Chemotherapy With Autologous Peripheral-Blood Stem-Cell Support Compared With Standard-Dose Chemotherapy in Women With Metastatic Breast Cancer: NCIC MA.16

PURPOSE We conducted a multicenter, randomized trial to compare progression-free survival (PFS), overall survival (OS), and quality of life in women with metastatic breast cancer (MBC) receiving high-dose chemotherapy plus autologous stem-cell transplantation (ASCT; HDCT) compared with standard-dose therapy. PATIENT AND METHODS Between April 1997 and December 2000, 386 women with MBC and no prior chemotherapy for metastatic disease were registered. After initial response to anthracycline- or taxane-based induction chemotherapy, 224 patients were randomly assigned: 112 to high-dose cyclophosphamide, mitoxantrone, and carboplatin chemotherapy and ASCT (HDCT), and 112 to standard therapy (ST). Median age was 47 years (range, 25 to 67 years). Thirty two percent of women randomly assigned had estrogen and progesterone receptor-negative breast cancer, 42% had visceral metastases, and 58% had bone metastases. Complete remission rates before random assignment were 11% for those receiving HDCT and 12% for those receiving ST. RESULTS After a median follow-up of 48 months, 79 deaths were observed in the HDCT arm and 77 deaths were observed in the ST arm; seven patients (6%) in the HDCT arm died as a result of toxicity. The median OS was 24 months for the HDCT arm (95% CI, 21 to 35 months) and 28 months for ST (95% CI, 22 to 33 months; hazard ratio [HR], 0.9; 95% CI, 0.6 to 1.2; P = .43). PFS was 11 months for HDCT and 9 months for ST (HR, 0.6 in favor of HDCT; 95% CI, 0.5 to 0.9; P = .006). CONCLUSION HDCT did not improve OS in women with MBC when used as consolidation after response to induction chemotherapy.

Comparison of CD34 and Monocyte‐Derived Dendritic Cells from Mobilized Peripheral Blood from Cancer Patients

Dendritic cells (DCs) are potent antigen‐presenting cells that are integral to the initiation of T‐cell immunity. Two cell types can be used as a source for generating DCs: monocytes and CD34+ stem cells. Despite many investigations characterizing DCs, none have performed a direct paired comparison of monocyte and stem cell–derived DCs. Therefore, it is unclear whether one cell source has particular advantages over the other, or whether inherent differences exist between the two populations. We undertook the following study to determine if there were any differences in DCs generated from monocytes or CD34+ cells from mobilized peripheral blood. DCs were generated by culturing the adherent cells (monocytes) in interleukin‐4 and GM‐CSF for 7 days, or by culturing nonadherent cells (CD34+) in the presence of GM‐CSF and tumor necrosis factor alpha for 14 days. The resulting DCs were compared morphologically, phenotypically, functionally, and by yield. We could generate morphologically and phenotypically similar DCs. Differences were encountered when expression levels of some cell surface markers were examined (CD86, HLA‐DR). There was no difference in how the DCs performed in a mixed lymphocyte reaction (p = .3). Further, no statistical difference was discovered when we examined cellular (DC) yield (p = .1); however, there was a significant difference when yield was normalized to the starting number of monocytes or CD34+ cells (p = .016). Together, these data demonstrate that differences do exist between monocyte‐derived DCs and CD34‐derived DCs from the same cellular product (apheresis) from the same individual.

Generation of dendritic cells ex vivo: differences in steady state versus mobilized blood from patients with breast cancer, with lymphoma, and from normal donors.

Dendritic cells (DC) are potent antigen-presenting cells that are integral to the initiation of T cell immunity. The ability to culture these cells in vitro has allowed DC immunotherapy to be investigated as a mechanism of enhancing immune responses against various malignancies. We examined the optimal time for generating DC and compared DC generated from normal donors for allogeneic blood stem cell transplantation, or patients with non-Hodgkins lymphoma or breast cancer undergoing high-dose chemotherapy and autologous stem cell transplantation. Experiments were conducted to compare DC cultured prior to and post mobilization chemotherapy. Blood was obtained from consenting patients prior to granulocyte colony-stimulating factor (G-CSF) administration with (non-Hodgkin lymphoma and breast cancer) or without (normal donors) chemotherapy. A sample of apheresis product (AP) was obtained at the time of apheresis. DC were generated from peripheral blood mononuclear cells by culturing the adherent cells in the presence of interleukin-4 and granulocyte-macrophage colony-stimulating factor. Resultant DC were harvested and examined for yield, morphology, phenotype, and function. All cell populations yielded highly pure DC, as assessed by light microscopy and flow cytometry. The average cellular yield was significantly greater from AP than steady-state blood in paired and unpaired samples. Yield did not correlate with the percentage of CD14(+) cells, and it negatively correlated with CD34 counts. DC from breast cancer patients functioned significantly better than DC from lymphoma patients in a mixed lymphocyte reaction. These data suggest that the optimal timing of culturing DC is after mobilization, and that differences may exist in the functional capabilities of DC derived from different patient populations.

A Canadian evidence-based guideline for the first-line treatment of follicular lymphoma: joint consensus of the Lymphoma Canada Scientific Advisory Board.

Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma (NHL) in North America. Because of the heterogeneity of the disease, treatment options vary from observation to aggressive therapies or stem cell transplantation, or both. Although advances in treatment have improved outcomes, the disease remains largely incurable. In Canada, no unified national guideline exists for the front-line treatment of FL; provincial guidelines vary and are largely based on funding. There is therefore a need for evidence-based national treatment guidelines that are supported by Canadian hematologists to ensure that patients with FL have equitable access to the best available care. A group of experts from across Canada developed a national evidence-based treatment guideline to provide health care professionals with clear guidance on the first-line management of FL. Results of a systematic review of the literature are presented with consensus recommendations based on available evidence.

Priming with dendritic cells can generate strong cytotoxic T cell responses to chronic myelogenous leukemia cells in vitro.

Dendritic cells (DC) are antigen-presenting cells that can elicit potent antigen-specific responses. Since the development of techniques to cultivate these cells from peripheral blood, there has been a great deal of interest in their use in immunotherapeutic strategies. Here we show that morphologically, phenotypically, and functionally characteristic DC can be generated in vitro from peripheral blood mononuclear cells (PBMC) isolated from frozen apheresis product (AP) of cancer patients. These DC, when pulsed with whole-tumor lysate, protein, or RNA from a chronic myelogenous leukemia (CML) cell line, can induce anti-CML specific cytotoxicity in vitro by autologous cytotoxic T lymphocytes (CTL). RNA and protein-pulsed DC were more effective than lysate-pulsed DC at inducing cytotoxicity at low effector:target (E:T) ratios. These results were comparable to those obtained when fresh healthy peripheral blood was used as the source of PBMC, indicating that neither the malignant state of the patient nor the storage period detrimentally affected the generation or functionality of DC. CML cells were found to increase their level of MHC class I expression after exposure to CTL and pulsed DC thereby becoming better targets. These investigations lend support for the utilization of DC to generate anti-tumor responses in CML.