Randomized Trial of Lenalidomide Versus Observation in Smoldering Multiple Myeloma.

PURPOSE: Observation is the current standard of care for smoldering multiple myeloma. We hypothesized that early intervention with lenalidomide could delay progression to symptomatic multiple myeloma. METHODS: We conducted a randomized trial that assessed the efficacy of single-agent lenalidomide compared with observation in patients with intermediate- or high-risk smoldering multiple myeloma. Lenalidomide was administered orally at a dose of 25 mg on days 1 to 21 of a 28-day cycle. The primary end point was progression-free survival, with disease progression requiring the development of end-organ damage attributable to multiple myeloma and biochemical progression. RESULTS: One hundred eighty-two patients were randomly assigned-92 patients to the lenalidomide arm and 90 to the observation arm. Median follow-up is 35 months. Response to therapy was observed in 50% (95% CI, 39% to 61%) of patients in the lenalidomide arm, with no responses in the observation arm. Progression-free survival was significantly longer with lenalidomide compared with observation (hazard ratio, 0.28; 95% CI, 0.12 to 0.62; P = .002). One-, 2-, and 3-year progression-free survival was 98%, 93%, and 91% for the lenalidomide arm versus 89%, 76%, and 66% for the observation arm, respectively. Only six deaths have been reported, two in the lenalidomide arm versus four in the observation arm (hazard ratio for death, 0.46; 95% CI, 0.08 to 2.53). Grade 3 or 4 nonhematologic adverse events occurred in 25 patients (28%) on lenalidomide. CONCLUSION: Early intervention with lenalidomide in smoldering multiple myeloma significantly delays progression to symptomatic multiple myeloma and the development of end-organ damage.

Increased natural killer cells and decreased regulatory T cells are seen in complex atypical endometrial hyperplasia and well-differentiated carcinoma treated with progestins.

Progestins are used to treat complex atypical hyperplasia and well-differentiated endometrial carcinoma in women who desire fertility preservation and those who are poor surgical candidates. Although sensitivity to progestins is thought to be associated with the presence of estrogen and progesterone receptors, it is known that receptor-negative tumors can also respond to the agent, suggesting that there is another direct antitumor action of progestin. Because tumor immune response is an additional predictor of survival in well-differentiated endometrial carcinoma, it is surprising that the role of progestins in tumor immunity has not been investigated. Regulatory T cells modulate the immune response, whereas cytotoxic T cells directly target tumor cells. In this study, we investigated the effect of progestins on regulatory T cells and cytotoxic T cells. The pre- and posttreatment endometrial samples of 15 progestin-treated patients with complex atypical hyperplasia or well-differentiated endometrial carcinoma were evaluated for therapeutic response and the presence of cytotoxic T cells and regulatory T cells. Immunohistochemical analysis was performed for FOXP3 to identify regulatory T cells and for granzyme B to identify activated cytotoxic T cells. To further characterize the cytotoxic T cell's subpopulations, we performed CD8 (cytotoxic T-cell marker) and CD56 (natural killer cells marker). Ten of 15 patients had normal morphology on follow-up endometrial samplings, and 4 patients had persistence or progression of the disease. Regulatory T-cell counts pretreatment were significantly higher in complex atypical hyperplasia and well-differentiated endometrial carcinoma than in posttreatment normal endometrium. Residual complex atypical hyperplasia and well-differentiated endometrial carcinoma present in posttreatment samples maintained high regulatory T cells and low number of cytotoxic T cells. Progestin treatment was associated with striking increase in cytotoxic T cells in areas with decidual reaction. Before treatment, most of the granzyme B+ cytotoxic T cells in complex atypical hyperplasia and well-differentiated endometrial carcinoma were CD8(+) T cells, whereas after treatment, up to 80% of cytotoxic T cells were natural killer cells. These results suggest that progestin treatment affects subpopulations of lymphocytes in the endometrium and may induce immune suppression of complex atypical hyperplasia and well-differentiated endometrial carcinoma.

Foxp3-expressing T regulatory cells and mast cells in acute graft-versus-host disease of the skin.

Acute graft-versus-host disease (aGVHD) limits the effectiveness of allogeneic hematopoietic stem cell transplantation. Foxp3 is required for the development and function of CD4(+)/CD25(+) regulatory T cells (T-regs). Foxp3-expressing T-regs are thought to protect against GVHD. Mast cells are thought to be essential in CD4(+)/CD25(+) regulatory T cell-dependent peripheral tolerance. Twenty biopsies of skin with grades I-III aGVHD were stained for Foxp3 and CD117. Inflammation was quantified by a 4 point scale, 0 = no inflammation, 1 = <25% of 20x field, 2 = 25-50%, and 3 = >50%. T-regs and mast cells were quantified by a 4 point scale, 0 = no cells per 20x field, 1 = <5 cells per 20x field, 2 = 5-10 cells, and 3 = >10 cells. T-regs were positively correlated with both inflammation and aGVHD grade. Twelve cases with low T-regs had mild inflammation and lower grades of aGVHD and 6 cases with high T-regs had dense inflammatory infiltrate and higher grades of aGVHD. The number of T-regs, mast cells and density of the inflammatory infiltrate were positively correlated only in cases with mild inflammation. In aGVHD of the skin, T-regs increased with the degree of inflammation and GVHD grade. Mast cells were present at the same density whether aGVHD was of lower or higher grade.

Expression of indoleamine 2,3-dioxygenase in metastatic malignant melanoma recruits regulatory T cells to avoid immune detection and affects survival.

The mechanism by which malignant melanoma (MM) cells survive in lymph nodes is poorly understood. One possible mechanism by which MM cells can escape immune surveillance is through upregulation of immunomodulatory enzymes such as indoleamine 2,3-dioxygenase (IDO). In this study, 25 cases of MM lymph node metastases from patients with long and short survival were evaluated for expression of IDO and the number of Forkhead box p3 (FOXP3)-expressing regulatory T cells. Moderate to strong cytoplasmic IDO expression was present in all (15/15) MM lymph node metastases in patients with poor survival. Eight of 10 patients with metastatic MM and long survival were negative or only weakly positive for IDO. Upregulation of IDO in metastatic MM cells was associated with an increased number of regulatory T cells (Tregs). There was a statistically significant association between shorter survival and both a stronger IDO expression (p = 0.0019) and a higher number of FOXP3 expressing Tregs (p < 0.001). Using RT-PCR analysis, we showed that IDO expression in MM cells is induced by interferon-gamma. These data support the notion that metastatic MM cells select for expression of IDO to evade immunologic detection. Therefore, inhibition of IDO in MM patients may be a useful treatment strategy.

Lack of effect of donor-recipient Rh mismatch on outcomes after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: A recently published study has reported that donor-recipient Rhesus (Rh)-mismatched allogeneic hematopoietic stem cell transplantation independently led to significantly poorer survival. This suggests that donor-recipient Rh mismatching is a risk factor in allogeneic hematopoietic stem cell transplantation and should be a criterion for donor selection. STUDY DESIGN AND METHODS: To further evaluate this issue, 258 consecutive patients who underwent myeloablative or submyeloablative allogeneic hematopoietic stem cell transplantation at our institution were analyzed to determine the association between the Rh mismatch pattern and 5-year actuarial survival. Secondary endpoints analyzed were the association of donor-recipient Rh mismatch and event-free survival, transplant-related mortality, incidence of acute graft-versus-host disease (GVHD), and incidence of chronic GVHD. RESULTS: In our analysis, there were no significant associations between donor-recipient Rh mismatch pattern and overall survival, event-free survival, transplant-related mortality, incidence of acute GVHD, or incidence of chronic GVHD. On multivariate Cox proportional hazard analyses, the donor-recipient Rh mismatch pattern was not independently predictive of overall survival. CONCLUSION: Donor-recipient Rh mismatch is not a risk factor in allogeneic hematopoietic stem cell transplantation and does not affect transplant outcomes.

Mixed chimerism and graft failure following conditioning with the fludarabine and cyclophosphamide nonablative regimen; conversion to full donor chimerism.

Twenty-one patients with hematologic malignancies were treated with the fludarabine (120-125 mg/m(2)) and cyclophosphamide (120 mg/kg) nonmyeloablative conditioning regimen. Graft versus host disease (GVHD) and graft rejection prophylaxis was with tacrolimus and mycophenolate mofetil. Thirteen of the 21 patients (62%) had mixed chimerism (< or = 90% donor cells) at day 60 and 11 (52%) of these patients had mixed chimerism which persisted until day 100. Immunosuppression was discontinued in 12 of 13 patients and two of them converted to full chimerism by day 100. Eight patients received a donor lymphocyte infusion (DLI) and five of them converted to full donor chimerism with DLI alone. Two patients were given GM-CSF in addition to a DLI with conversion to full donor chimerism. Three patients (14%) had graft failure requiring a second transplant using fludarabine (125 mg/m(2)) and melphalan (140 mg/m(2)). With a median followup of 2.8 years, 15 patients are alive - one with disease and 14 with no disease. Two patients died of acute GVHD, one of chronic GVHD, and three due to progressive disease. We conclude that the nonmyeloablative fludarabine/cyclophosphamide regimen results in a significant incidence of mixed chimerism and graft rejection but is well tolerated. We suggest a more intense regimen, such as fludarabine and melphalan, be used in patients with a high risk of early disease progression to establish early engraftment and graft versus tumor effect.

Low-dose total body irradiation followed by allogeneic lymphocyte infusion may induce remission in patients with refractory hematologic malignancy.

Allogeneic stem cell transplantation is curative for certain cancers, but the high doses of chemotherapy/radiotherapy lead to toxicity. Here, we treat patients with refractory cancer with 100 cGy total body irradiation (TBI) followed by infusion of nonmobilized pheresed allogeneic peripheral blood cells. Twenty-five patients, with a median age of 47 years, with refractory cancers were enrolled. Eighteen patients received sibling and 7 received unrelated cord blood cells. Donor chimerism was assessed at weeks 1, 2, 3, 4, and 8 after transplantation. Seven patients with solid tumors received a sibling transplant and 6 received a cord blood transplant; none achieved donor chimerism, but 1 treated at the higher dose level of 1 x 10(8) CD3+ cells/kg had a transient nodal response. Twelve patients with hematologic malignancies were treated; 1 received a cord blood transplant and 11 received sibling donor cells. Nine of these 11 patients achieved donor chimerism, ranging from 5% to 100%. Four patients had sustained complete remission of their cancers, including one patient with transient 5% donor chimerism. The development of chimerism correlated with hematologic malignancy (P <.001), total previous myelotoxic chemotherapy (P <.001), T-cell dose (P =.03), and graft-versus-host disease (P =.01). Tumor response correlated with donor chimerism (P =.01). Engraftment was achieved in patients with hematologic malignancies who had been heavily pretreated, suggesting the degree of immunosuppression may be a determinant of engraftment. Low-dose TBI and allogeneic lymphocyte infusion may induce remission in patients with refractory hematologic malignancy.