Geyer, Susan M.

Multiple myeloma is a highly radiosensitive skeletal malignancy, but bone-seeking radionuclides have not yet found their place in disease management. We previously reported that the proteasome inhibitor PS-341 selectively sensitizes myeloma cells to the lethal effects of ionizing radiation. To extend these observations to an in vivo model, we combined PS-341 with the bone-seeking radionuclide 153-Sm-EDTMP. In vitro clonogenic assays demonstrated synergistic killing of myeloma cells exposed to both PS-341 and 153-Sm-EDTMP. Using the orthotopic, syngeneic 5TGM1 myeloma model, the median survivals of mice treated with saline, 2 doses of PS-341 (0.5 mg/kg), or a single nonmyeloablative dose of 153-Sm-EDTMP (22.5 MBq) were 21, 22, and 28 days, respectively. In contrast, mice treated with combination therapy comprising 2 doses of PS-341 (0.5 mg/kg), 1 day prior to and 1 day following 153-Sm-EDTMP (22.5 MBq) showed a significantly prolonged median survival of 49 days (P < .001). In addition to prolonged survival, this treatment combination yielded reduced clonogenicity of bone marrow–resident 5TGM1 cells, reduced serum myeloma–associated paraprotein levels, and better preservation of bone mineral density. Myelosuppression, determined by peripheral blood cell counts and clonogenicity assays of hematopoietic progenitors, did not differ between animals treated with 153-Sm-EDTMP alone versus those treated with the combination of PS-341 plus 153-Sm-EDTMP. PS-341 is a potent, selective in vivo radiosensitizer that may substantially affect the efficacy of skeletal-targeted radiotherapy in multiple myeloma.

We report the results of a phase 2 trial using lenalidomide plus dexamethasone (Rev/Dex) as initial therapy for myeloma. Thirtyfour patients were enrolled. Lenalidomide was given orally 25 mg daily on days 1 to 21 of a 28-day cycle. Dexamethasone was given orally 40 mg daily on days 1 to 4, 9 to 12, and 17 to 20 of each cycle. Objective response was defined as a decrease in serum monoclonal protein level by 50% or greater and a decrease in urine M protein level by at least 90% or to a level less than 200 mg/24 hours, confirmed by 2 consecutive determinations at least 4 weeks apart. Thirty-one of 34 patients achieved an objective response, including 2 (6%) achieving complete response (CR) and 11 (32%) meeting criteria for both very good partial response and near complete response, resulting in an overall objective response rate of 91%. Of the 3 remaining patients not achieving an objective response, 2 had minor response (MR) and one had stable disease. Fortyseven percent of patients experienced grade III or higher nonhematologic toxicity, most commonly fatigue (15%), muscle weakness (6%), anxiety (6%), pneumonitis (6%), and rash (6%). Rev/Dex is a highly active regimen with manageable side effects in the treatment of newly diagnosed myeloma.

PurposeMantle cell lymphoma (MCL) is characterized by a t(11;14) resulting in overexpression of cyclin D1 messenger RNA. This study tested whether temsirolimus (previously known as CCI-779), an inhibitor of the mammalian target of rapamycin kinase that regulates cyclin D1 translation, could produce tumor responses in patients with MCL.Patients and MethodsPatients with relapsed or refractory MCL were eligible to receive temsirolimus 250 mg intravenously every week as a single agent. Patients with a tumor response after six cycles were eligible to continue drug for a total of 12 cycles or two cycles after complete remission, and were then observed without maintenance.ResultsThirty-five patients were enrolled and were assessable for toxicity; one patient had MCL by histology but was cyclin D1 negative and was ineligible for efficacy. The median age was 70 years (range, 38 to 89 years), 91% were stage 4, and 69% had two or more extranodal sites. Patients had received a median of three prior therapies (range, one to 11), and 54% were refractory to the last treatment. The overall response rate was 38% (13 of 34 patients; 90% CI, 24% to 54%) with one complete response (3%) and 12 partial responses (35%). The median time-to-progression in all patients was 6.5 months (95% CI, 2.9 to 8.3 months), and the duration of response for the 13 responders was 6.9 months (95% CI, 5.2 to 12.4 months). Hematologic toxicities were the most common, with 71% (25 of 35 patients) having grade 3 and 11% (four of 35 patients) having grade 4 toxicities observed. Thrombocytopenia was the most frequent cause of dose reductions but was of short duration, typically resolving within 1 week.ConclusionsSingle-agent temsirolimus has substantial antitumor activity in relapsed MCL. This study demonstrates that agents that selectively target cellular pathways dysregulated in MCL cells can produce therapeutic benefit. Further studies of this agent in MCL and other lymphoid malignancies are warranted.

Purpose Patients with newly diagnosed, advanced-stage, follicular grade 1 non-Hodgkin's lymphoma (NHL) are often asymptomatic and can be observed without immediate chemotherapy. The goals of this study were to assess the overall response rate (ORR) to rituximab in this patient population and to determine the time-to-progression (TTP) and time-to-subsequent-chemotherapy (TTSC). Patients and Methods Eligible patients had untreated follicular grade 1 NHL, and measurable stage III/IV disease. Patients received rituximab 375 mg/m2 intravenous weekly × 4 doses and were then followed for response and progression; no maintenance therapy was provided. Results Thirty-seven patients were accrued; one patient was ineligible. The median age was 59 years (range, 29 to 83 years). Six patients (18%) had elevated lactate dehydrogenase levels. The ORR was 72%, with 36% complete remissions. Fourteen (39%) of 36 patients remain in unmaintained remission, two died without disease progression, and three died with disease progression. Twenty (56%) of 36 patients have disease progression. The median TTP was 2.2 years (95% CI, 1.3 to not yet reached). Eighteen patients have subsequently been treated with chemotherapy, with a median TTSC of 2.3 years (95% CI, 1.6 to not yet reached). Patients with a high lactate dehydrogenase level had a lower ORR of 33% and a short TTP of only 6 months. Conclusion Rituximab can be safely administered to patients with advanced-stage follicular grade 1 NHL with efficacy and minimal toxicity. This therapy is highly active and offers an acceptable alternative to observation in this patient population. Patients with high LDH should not be considered for rituximab monotherapy.

AbstractB-cell chronic lymphocytic leukemia (CLL) is characterized by accumulation of clonal lymphocytes resistant to apoptosis. We evaluated the ability of the investigational antileukemic agent adaphostin to induce apoptosis in CLL B cells and synergize with fludarabine in vitro. Analysis by annexin V/propidium iodide (PI) staining revealed that the concentration of adaphostin required to induce 50% cell death (IC50) at 24 hours was 4.2 μM (range, 1.10-11.25 μM; median, 4.25 μM; n = 29) for CLL isolates and more than 10 μM for B and T cells from healthy donors. Immunoblots demonstrated adaphostin induced poly(adenosine diphosphate-ribose) polymerase (PARP) cleavage and cleavage of caspase-3 substrates, suggesting that adaphostin induces apoptosis. Adaphostin increased the level of reactive oxygen species (ROS) within CLL B cells, and the antioxidant N-acetylcysteine blocked both adaphostin-induced ROS generation and apoptosis. Adaphostin also caused a decrease in the level of the antiapoptotic protein Bcl-2. When adaphostin was combined with fludarabine (F-ARA-AMP), a synergistic effect on cell death was observed in all 10 CLL samples. These findings not only indicate that adaphostin induces apoptosis selectively in CLL B cells through a mechanism that involves ROS generation but also demonstrate its ability to augment the effects of fludarabine. Further preclinical development of adaphostin as a novel agent for the treatment of CLL appears warranted.

Abstract Heterogeneity in the clinical behavior of patients with chronic lymphocytic leukemia (CLL) makes it difficult for physicians to accurately identify which patients may benefit from an early or more aggressive treatment strategy and to provide patients with relevant prognostic information. Given the potential efficacy of newer therapies and the desire to treat patients at “optimum” times, it is more important than ever to develop sensitive stratification parameters to identify patients with poor prognosis. The evolution of risk stratification models has advanced from clinical staging and use of basic laboratory parameters to include relevant biologic and genetic features. This article will review the dramatic progress in prognostication for CLL and will propose statistical modeling techniques to evaluate the utility of these new measures in predictive models to help determine the optimal combination of markers to improve prognostication for individual patients. This discussion will also elaborate which markers and tools should be used in current clinical practice and evaluated in ongoing clinical trials.

Purpose: The North Central Cancer Treatment Group performed a phase III trial to determine whether chemotherapy plus either bid radiation therapy (RT) or daily (qd) RT resulted in a better outcome for patients with stage III non–small-cell lung cancer (NSCLC). No difference in survival was identified between the two arms. This secondary analysis was performed to examine the relationship between patient age and outcome. Patients and Methods: Two hundred forty-six patients were randomized to receive etoposide plus cisplatin and either RT qd or split-course RT bid. This retrospective study compared the outcomes of patients aged ≥70 years (“elderly patients”) with those of younger individuals. Of the 244 assessable patients, 63 (26%) were elderly, and 181 (74%) were younger individuals. Results: The 2-year and 5-year survival rates were 39% and 18%, respectively, in patients younger than 70 years, compared with 36% and 13%, respectively, in elderly patients (P = .4). Grade 4+ toxicity occurred in 62% of patients younger than 70 years compared with 81% of elderly patients (P = .007). Grade 4+ hematologic toxicity occurred in 56% of patients younger than 70 years, compared with 78% of elderly patients (P = .003). Grade 4+ pneumonitis occurred in 1% of those younger than 70 years, compared with 6% of elderly patients (P = .02). Conclusion: Toxicity, especially myelosuppression and pneumonitis, was more pronounced in the elderly patients receiving combined-modality therapy for locally advanced NSCLC. Despite increased toxicity, elderly patients have survival rates equivalent to younger individuals. Therefore, fit, elderly patients with locally advanced NSCLC should be encouraged to receive combined-modality therapy, preferably on clinical trials with cautious, judicious monitoring. Future studies should explore ways to decrease toxicity of therapy in elderly patients.

AbstractLight chain–associated amyloidosis (AL) is a plasma cell dyscrasia in which the secreted monoclonal immunoglobulin (Ig) light chains form amyloid fibrils. There is considerable heterogeneity in clinical presentation, and prognosis of the disease relates to the severity of organ dysfunction induced by amyloid deposits. The mechanisms by which the amyloid fibrils are deposited as well as the predilection for specific organ sites have not been clearly elucidated. This study characterizes the repertoire of immunoglobulin light chain variable genes used by the clonal B cell in AL amyloid patients, and the association of light chain variable region (VL) genes with clinical presentation and outcome is assessed in 58 (32 λ and 26 κ) patients. A preferential use of VL germ-line genes was noted for both AL κ and λ patients. There was a significant correlation between the use of the Vλ VI germ-line donor, 6a, and renal involvement as well as the Vλ III gene, 3r, with soft-tissue AL. The use of a biased VL gene repertoire also correlated with clinical outcome, revealing important trends for predicting prognosis. The use of Vλ II germ-line genes was associated with cardiac amyloidosis and affected survival adversely. The presence of multiple myeloma also correlated with a poor prognosis. The presence of renal disease, on the other hand, was associated with improved survival. Therefore, identification of the clonal VL gene in AL has important implications in determining clinical outcome.

Purpose: This phase II study was undertaken to define the efficacy and pharmacodynamics of R115777, a farnesyl transferase inhibitor, in the first-line treatment of patients with advanced non–small-cell lung cancer. Patients and Methods: Forty-four patients with measurable stage IIIB (pleural effusion) or stage IV disease received 193 courses of treatment (median, 2.0; range, 1 to 22) with R115777 300 mg administered orally twice daily for 21 of every 28 days. Buccal mucosa samples and peripheral blood mononuclear cells (PBMCs) were collected before and after 8 days of treatment to evaluate inhibition of farnesyl transferase in vivo. Results: No objective complete or partial responses were documented. Seven patients (16%; 95% confidence interval [CI], 8% to 31%) had disease stabilization for greater than 6 months. Median survival was 7.7 months (95% CI, 6.5 to 10.5) and time to progression was 2.7 months (95% CI, 1.9 to 3.1). The most severe toxicity was neutropenia (9% grade 3, 7% grade 4) and the most common toxicities were anemia (50% grade 1 or 2, 5% grade 3) and anorexia (50% grade 1 or 2, 2% grade 3). Mild peripheral neuropathy occurred in 25% of patients. Evidence of farnesyl transferase inhibition was documented in 83% of patients. Conclusion: Single-agent R115777 was well tolerated in patients with advanced NSCLC, but demonstrated minimal clinical activity. Inhibition of farnesylation in vivo was consistently documented. On the basis of promising results of farnesyl transferase inhibitor combinations with standard chemotherapy agents, future studies of this agent in NSCLC should be in combination with systemic chemotherapy.

PURPOSE: Multiple myeloma is a malignancy of plasma cells and is characterized by increased marrow angiogenesis. Thalidomide, an agent with antiangiogenic properties, is effective in relapsed myeloma. We report the results of a study combining thalidomide and dexamethasone as initial therapy for myeloma. PATIENTS AND METHODS: Fifty patients with newly diagnosed myeloma were studied. Thalidomide was given at a dose of 200 mg/d orally. Dexamethasone was given at a dose of 40 mg/d orally on days 1 to 4, 9 to 12, and 17 to 20 (odd cycles) and 40 mg/d on days 1 to 4 (even cycles), repeated monthly. RESULTS: Of all 50 patients, a confirmed response was seen in 32 patients yielding a response rate of 64% (95% confidence interval, 49% to 77%). Thirty-one patients (62%) proceeded to stem-cell collection after four cycles of therapy including 26 who underwent stem-cell transplantation and five who chose stem-cell cryopreservation. Major grade 3 or 4 toxicities were observed in 16 patients (32%), and the most frequent were deep vein thrombosis (six patients), constipation (four patients), rash (three patients), and dyspnea (two patients). Three deaths occurred during active therapy because of a pancreatitis, pulmonary embolism, and infection. CONCLUSION: We conclude that the combination of thalidomide plus dexamethasone is a feasible and active regimen in the treatment of multiple myeloma. It merits further study as an oral alternative to infusional chemotherapy with vincristine, doxorubicin, and dexamethasone and other intravenous regimens currently used as pretransplantation induction therapy for myeloma.