William R. Drobyski

Donor leukocyte infusions in 140 patients with relapsed malignancy after allogeneic bone marrow transplantation.

PURPOSE Recipients of allogeneic bone marrow transplants (BMTs) who have relapsed may attain complete remissions when treated with transfusions of leukocytes obtained from the original bone marrow donor. We performed a retrospective study to characterize better this new treatment modality. PATIENTS AND METHODS We surveyed 25 North American BMT programs regarding their use of donor leukocyte infusions (DLI). Detailed forms were used to gather data regarding the original BMT, relapse, DLI, response to DLI, complications of DLI, and long-term follow-up evaluation. Reports of 140 patients were thus available for analysis. RESULTS Complete responses were observed in 60% (95% confidence interval [CI], 51.9% to 68.1%) of chronic myelogenous leukemia (CML) patients who received DLI and did not receive pre-DLI chemotherapy; response rates were higher in patients with cytogenetic and chronic-phase relapse (75.7%; 95% CI, 68.2% to 83.2%) than in patients with accelerated-phase (33.3%; 95% CI, 19.7% to 46.9%) or blastic-phase (16.7%; 95% CI, 1.9% to 31.9%) relapse. The actuarial probability of remaining in complete remission at 2 years was 89.6%. Complete remission rates in acute myelogenous leukemia (AML) (n = 39) and acute lymphocytic leukemia (ALL) (n = 11) patients who had not received pre-DLI chemotherapy were 15.4% (95% CI, 9.6% to 21.2%) and 18.2% (95% CI, 6.6% to 29.8%), respectively. Complete remissions were also observed in two of four assessable myeloma patients and two of five assessable myelodysplasia patients. Complications of DLI included acute graft-versus-host disease (GVHD) (60%; 95% CI, 51.4% to 68.6%), chronic GVHD (60.7%; 95% CI, 50.3% to 71.1%), and pancytopenia (18.6%; 95% CI, 12.2% to 25.0%). Pre-DLI characteristics predictive of complete response in CML patients were post-BMT chronic GVHD, pre-DLI disease status of chronic phase, and time interval between BMT to DLI less than 2 years. Acute and chronic GVHD post-DLI were highly correlated with disease response (P < .00001). CONCLUSION DLI results in complete remissions in a high percentage of patients with relapsed chronic-phase CML. Complete remissions are observed less frequently in patients with advanced CML and acute leukemia. GVHD and pancytopenia occur commonly; GVHD is highly correlated with response.

Sensitive detection of occult breast cancer by the reverse-transcriptase polymerase chain reaction.

PURPOSE Detection of occult carcinoma in patients with breast cancer may aid the establishment of prognosis and development of new therapeutic approaches. To improve on existing methods of detection, we have developed a reverse-transcriptase polymerase chain reaction (RT-PCR) assay for keratin 19 (K19) transcripts to identify mammary carcinoma cells in the peripheral blood and bone marrow of patients with breast cancer. PATIENTS AND METHODS Peripheral-blood or bone marrow samples obtained from 34 patients with stages I to IV breast cancer and 39 control subjects without breast cancer were screened for K19 mRNA by nested primer PCR. RESULTS In reconstitution experiments, K19 RT-PCR reliably detected 10 mammary carcinoma cells in 1 million normal peripheral-blood mononuclear (PBMN) cells. Four of 19 patients with stage IV breast cancer had detectable K19 transcript in peripheral blood. Five of six patients with histologically negative bone marrow biopsies following preablative chemotherapy and before autologous bone marrow transplant (BMT) were positive by this assay. Stem-cell apheresis harvests obtained from one of these patients and three additional patients immediately before BMT were all K19-negative. K19 RT-PCR analysis of CSF from a breast cancer patient with known carcinomatous meningitis was also positive. Thirty-eight of 39 non-breast cancer patients had negative K19 RT-PCR assays. The one exception was a patient with chronic myelogenous leukemia. CONCLUSION RT-PCR of K19 is a sensitive, specific, and rapid method for detection of occult mammary carcinoma cells in the peripheral blood and bone marrow of patients with breast cancer. The presence of residual breast cancer cells in histologically normal bone marrow aspirates but not in stem-cell apheresis harvests is a frequent finding. This assay may be useful in diagnosing metastatic disease, as well as in monitoring the effectiveness of systemic therapy.

Interstitial pneumonitis associated with human herpesvirus-6 infection after marrow transplantation

Severe interstitial pneumonitis in 2 marrow-transplant recipients was associated with human herpesvirus-6 (HHV-6) infection. The virus was repeatedly detected in respiratory specimens from 1 patient, and HHV-6-infected cells were shown in lung tissue from both patients by immunohistochemical staining. The infected cells were primarily intra-alveolar macrophages, although infected lymphocytes were seen. HHV-6 should be considered as a cause of unexplained lung disease in marrow-transplant recipients and other immunocompromised patients.

Prospective trial of chemotherapy and donor leukocyte infusions for relapse of advanced myeloid malignancies after allogeneic stem-cell transplantation

PURPOSE Patients with advanced myeloid malignancies who experience relapse after allogeneic bone marrow transplantation (BMT) have a poor prognosis. Long-term survival after chemotherapy alone, second myeloablative transplant, or donor leukocyte infusions (DLIs) alone is unusual. DLIs may have minimal effectiveness in advanced disease because adequate cellular responses are not able to develop in the presence of bulky, fast-growing disease. A chemotherapy strategy was used to debulk disease before administration of granulocyte colony-stimulating factor (G-CSF)-primed DLIs. PATIENTS AND METHODS Sixty-five patients experiencing hematologic relapse of myeloid malignancy after HLA-matched sibling BMT were prospectively treated with cytarabine-based chemotherapy, then G-CSF-primed DLIs. No prophylactic immunosuppression was provided. RESULTS Twenty-seven of 57 assessable patients experienced a complete response. Graft-versus-host disease (GVHD) was observed in 56% of the patients. Treatment-related mortality was 23%. Overall survival at 2 years for the entire cohort was 19%. Patients with a complete response were more likely to survive, with 1- and 2-year survival rates of 51% and 41%, respectively, with a median follow-up of more than 2 years. The 1-year survival for nonresponders was 5%. A posttransplant remission lasting more than 6 months before relapse was associated with a higher likelihood of response. GVHD was not required for durable remission. CONCLUSION Salvage treatment with chemotherapy before DLI can help some patients with advanced myeloid relapse and is not dependent on GVHD. Patients with short remissions after BMT are unlikely to benefit from this approach, and the approach is associated with significant treatment-related mortality. Modifications of this approach or entirely different approaches will be required for most patients with this difficult clinical problem.

Donor leukocyte infusions in acute lymphocytic leukemia.

Donor leukocyte infusion (DLI) has well-documented activity in CML but the role of DLI in other diseases is less well defined. To evaluate the strategy in acute lymphocytic leukemia (ALL) we evaluated 44 ALL patients from 27 centers who were treated with DLI. Patients with persistent or recurrent disease received DLI from the original marrow donor (30 matched related, four mismatched family, and 10 matched unrelated). Chemotherapy was given before DLI to 28 patients. Of 15 patients who received no pre-DLI chemotherapy, two achieved complete remissions, lasting 1112 and 764+ days. In four patients who received DLI as consolidation of remission induced by chemotherapy or immunosuppression-withdrawal, duration of remission post DLI was 65, 99, 195 and 672+ days. Of 25 patients who received DLI in the nadir after chemotherapy, 13 survived ⩾30 days post DLI but did not achieve remission, seven died within less than 30 days post DLI, and five entered remissions that lasted 42, 68, 83, 90, 193 days. Seven patients who did not respond to the initial DLI received a second DLI; none of these patients attained durable remission. Eighteen of 37 evaluable patients developed acute GVHD and five of 20 evaluable patients developed chronic GVHD. Overall actuarial survival is 13% at 3 years. In conclusion, DLI has limited benefit in ALL. New approaches are needed in this group of patients. Bone Marrow Transplantation (2000) 26, 511–516.

Blockade of interleukin-6 signaling augments regulatory T-cell reconstitution and attenuates the severity of graft-versus-host disease.

Graft-versus-host disease (GVHD) is the major complication after allogeneic bone marrow transplantation and is characterized by the overproduction of proinflammatory cytokines. In this study, we have identified interleukin-6 (IL-6) as a critical inflammatory cytokine that alters the balance between the effector and regulatory arms of the immune system and drives a proinflammatory phenotype that is a defining characteristic of GVHD. Our results demonstrate that inhibition of the IL-6 signaling pathway by way of antibody-mediated blockade of the IL-6 receptor (IL-6R) markedly reduces pathologic damage attributable to GVHD. This is accompanied by a significant increase in the absolute number of regulatory T cells (Tregs) that is due to augmentation of thymic-dependent and thymic-independent Treg production. Correspondingly, there is a significant reduction in the number of T helper 1 and T helper 17 cells in GVHD target organs, demonstrating that blockade of IL-6 signaling decreases the ratio of proinflammatory T cells to Tregs. These studies demonstrate that antibody blockade of the IL-6R serves to recalibrate the effector and regulatory arms of the immune system and represents a novel, potentially clinically translatable, strategy for the attenuation of GVHD.

Donor leukocyte infusions for multiple myeloma

Donor leukocyte infusion (dli) has well-documented activity in cml, but the role of dli in other diseases is less well defined. to evaluate the strategy in multiple myeloma (mm) we evaluated 25 mm patients from 15 centers who were treated with dli. patients with persistent or recurrent disease after allogeneic bmt received dli from the original marrow donor (23 matched related, one mismatched family, and one matched unrelated). chemotherapy was given before dli in three patients. two of 22 patients responded completely to dli alone and three patients responded to the combination of dli and chemotherapy. nine patients who had not had sufficient disease control after dli were given additional dlis; five of these patients had either complete (two) or partial (three) responses. thirteen of 25 evaluable patients developed acute gvhd and 11 of 21 evaluable patients developed chronic gvhd; all responders developed gvhd. no patients developed post-dli pancytopenia. four patients had responses which lasted >1 year after DLI, three patients had responses which lasted <1 year, and three patients had ongoing responses but with follow-up <1 year. In conclusion, DLI has anti-myeloma activity but the strategy is limited by no response or short duration of response in a significant percentage of patients and by significant GVHD in the majority of the responders. Bone Marrow Transplantation (2000) 26, 1179–1184.

Long-term results of selective renal shielding in patients undergoing total body irradiation in preparation for bone marrow transplantation

The purpose of this study was to evaluate the effect of partial renal shielding used in conjunction with total body irradiation (TBI) on the incidence of bone marrow transplantation nephropathy (BMT Np) seen as a late sequelae after transplantation. Of 402 patients who have undergone bone marrow transplantation (BMT) at the Medical College of Wisconsin (MCW) 157 were greater than 18 years of age, received 14 Gy TBI and survived at least 100 days post-transplant. The incidence of BMT nephropathy was evaluated in these patients by dose to the kidneys. In the 72 patients who received 14 Gy TBI with no renal shielding, the actuarial risk of developing BMT Np at 2½ years (30 months) post-BMT was 29 ± 7%. Sixty-eight patients received 14 Gy TBI with partial renal shielding of 15% (renal dose = 11.9 Gy), the actuarial risk of developing BMT Np was 14 ± 5% at 2½ years. Seventeen patients received 14 Gy TBI with renal shielding of 30% (renal dose = 9.8 Gy); none of this group have developed BMT Np despite a median follow-up of over 2½ years (985 days). The trend of decreasing BMT Np with increasing shielding is statistically significant (P = 0.012). Prognostic factors such as age, type of transplant and good-risk vs poor-risk disease status were evaluated and were similar in each cohort of patients described above. We conclude that given the statistically significant benefit seen here in the reduced incidence of BMT Np by the use of selective renal shielding, this should be seriously considered for all patients who receive TBI, but especially for patients whose renal doses exceed 10 Gy.

Increasing Incidence of Chronic Graft-versus-Host Disease in Allogeneic Transplantation: A Report from the Center for International Blood and Marrow Transplant Research

Although transplant practices have changed over the last decades, no information is available on trends in incidence and outcome of chronic graft-versus-host disease (cGVHD) over time. This study used the central database of the Center for International Blood and Marrow Transplant Research (CIBMTR) to describe time trends for cGVHD incidence, nonrelapse mortality, and risk factors for cGVHD. The 12-year period was divided into 3 intervals, 1995 to 1999, 2000 to 2003, and 2004 to 2007, and included 26,563 patients with acute leukemia, chronic myeloid leukemia, and myelodysplastic syndrome. Multivariate analysis showed an increased incidence of cGVHD in more recent years (odds ratio = 1.19, P < .0001), and this trend was still seen when adjusting for donor type, graft type, or conditioning intensity. In patients with cGVHD, nonrelapse mortality has decreased over time, but at 5 years there were no significant differences among different time periods. Risk factors for cGVHD were in line with previous studies. This is the first comprehensive characterization of the trends in cGVHD incidence and underscores the mounting need for addressing this major late complication of transplantation in future research.

Immunosuppressive Effects of Multiple Myeloma Are Overcome by PD-L1 Blockade

Multiple myeloma is an incurable plasma cell malignancy. Patients who fail conventional therapy are frequently treated with hematopoietic stem cell transplantation (HSCT), which results in reduced tumor burden, but the patients subsequently relapse from sites of chemotherapy-resistant disease. Using the 5T33 murine model of myeloma and a previously successful immunotherapy regimen consisting of autologous (syngeneic) HSCT and cell-based vaccine administration, we were unable to improve survival of myeloma-bearing mice. The 5T33 tumor line, similar to malignant plasma cells from myeloma patients, expresses high levels of programmed death receptor ligand-1 (PD-L1), which binds to the inhibitory receptor, PD-1. We observed that T cells from myeloma-bearing mice express high levels of PD-1, which has also been observed in patients with multiple myeloma. These PD-1(+) T cells were exhausted and produced IL-10. Based on these observations, we combined HSCT with whole-cell vaccination and PD-L1 blockade. Inhibition of the PD-1/PD-L1 pathway with HSCT and whole-cell vaccination increased the survival of myeloma-bearing mice from 0% to 40%. These data demonstrate a role for PD-L1 in suppressing immune responses to myeloma and suggest that blockade of this pathway may enhance immunotherapy for this disease.