The genomic landscape of Waldenstrom macroglobulinemia is characterized by highly recurring MYD88 and WHIM-like CXCR4 mutations, and small somatic deletions associated with B-cell lymphomagenesis.

The genetic basis for Waldenström macroglobulinemia (WM) remains to be clarified. Although 6q losses are commonly present, recurring gene losses in this region remain to be defined. We therefore performed whole genome sequencing (WGS) in 30 WM patients, which included germline/tumor sequencing for 10 patients. Validated somatic mutations occurring in >10% of patients included MYD88, CXCR4, and ARID1A that were present in 90%, 27%, and 17% of patients, respectively, and included the activating mutation L265P in MYD88 and warts, hypogammaglobulinemia, infection, and myelokathexis-syndrome-like mutations in CXCR4 that previously have only been described in the germline. WGS also delineated copy number alterations (CNAs) and structural variants in the 10 paired patients. The CXCR4 and CNA findings were validated in independent expansion cohorts of 147 and 30 WM patients, respectively. Validated gene losses due to CNAs involved PRDM2 (93%), BTG1 (87%), HIVEP2 (77%), MKLN1 (77%), PLEKHG1 (70%), LYN (60%), ARID1B (50%), and FOXP1 (37%). Losses in PLEKHG1, HIVEP2, ARID1B, and BCLAF1 constituted the most common deletions within chromosome 6. Although no recurrent translocations were observed, in 2 patients deletions in 6q corresponded with translocation events. These studies evidence highly recurring somatic events, and provide a genomic basis for understanding the pathogenesis of WM.

Carfilzomib, rituximab, and dexamethasone (CaRD) treatment offers a neuropathy-sparing approach for treating Waldenström's macroglobulinemia.

Bortezomib frequently produces severe treatment-related peripheral neuropathy (PN) in Waldenström's macroglobulinemia (WM). Carfilzomib is a neuropathy-sparing proteasome inhibitor. We examined carfilzomib, rituximab, and dexamethasone (CaRD) in symptomatic WM patients naïve to bortezomib and rituximab. Protocol therapy consisted of intravenous carfilzomib, 20 mg/m2 (cycle 1) and 36 mg/m(2) (cycles 2-6), with intravenous dexamethasone, 20 mg, on days 1, 2, 8, and 9, and rituximab, 375 mg/m(2), on days 2 and 9 every 21 days. Maintenance therapy followed 8 weeks later with intravenous carfilzomib, 36 mg/m(2), and intravenous dexamethasone, 20 mg, on days 1 and 2, and rituximab, 375 mg/m(2), on day 2 every 8 weeks for 8 cycles. Overall response rate was 87.1% (1 complete response, 10 very good partial responses, 10 partial responses, and 6 minimal responses) and was not impacted by MYD88(L265P) or CXCR4(WHIM) mutation status. With a median follow-up of 15.4 months, 20 patients remain progression free. Grade ≥2 toxicities included asymptomatic hyperlipasemia (41.9%), reversible neutropenia (12.9%), and cardiomyopathy in 1 patient (3.2%) with multiple risk factors, and PN in 1 patient (3.2%) which was grade 2. Declines in serum IgA and IgG were common. CaRD offers a neuropathy-sparing approach for proteasome inhibitor-based therapy in WM. This trial is registered at www.clinicaltrials.gov as #NCT01470196.

MYD88 L265P somatic mutation in Waldenström's macroglobulinemia.

BACKGROUND: Waldenström's macroglobulinemia is an incurable, IgM-secreting lymphoplasmacytic lymphoma (LPL). The underlying mutation in this disorder has not been delineated. METHODS: We performed whole-genome sequencing of bone marrow LPL cells in 30 patients with Waldenström's macroglobulinemia, with paired normal-tissue and tumor-tissue sequencing in 10 patients. Sanger sequencing was used to validate the findings in samples from an expanded cohort of patients with LPL, those with other B-cell disorders that have some of the same features as LPL, and healthy donors. RESULTS: Among the patients with Waldenström's macroglobulinemia, a somatic variant (T→C) in LPL cells was identified at position 38182641 at 3p22.2 in the samples from all 10 patients with paired tissue samples and in 17 of 20 samples from patients with unpaired samples. This variant predicted an amino acid change (L265P) in MYD88, a mutation that triggers IRAK-mediated NF-κB signaling. Sanger sequencing identified MYD88 L265P in tumor samples from 49 of 54 patients with Waldenström's macroglobulinemia and in 3 of 3 patients with non-IgM-secreting LPL (91% of all patients with LPL). MYD88 L265P was absent in paired normal tissue samples from patients with Waldenström's macroglobulinemia or non-IgM LPL and in B cells from healthy donors and was absent or rarely expressed in samples from patients with multiple myeloma, marginal-zone lymphoma, or IgM monoclonal gammopathy of unknown significance. Inhibition of MYD88 signaling reduced IκBα and NF-κB p65 phosphorylation, as well as NF-κB nuclear staining, in Waldenström's macroglobulinemia cells expressing MYD88 L265P. Somatic variants in ARID1A in 5 of 30 patients (17%), leading to a premature stop or frameshift, were also identified and were associated with an increased disease burden. In addition, 2 of 3 patients with Waldenström's macroglobulinemia who had wild-type MYD88 had somatic variants in MLL2. CONCLUSIONS: MYD88 L265P is a commonly recurring mutation in patients with Waldenström's macroglobulinemia that can be useful in differentiating Waldenström's macroglobulinemia and non-IgM LPL from B-cell disorders that have some of the same features. (Funded by the Peter and Helen Bing Foundation and others.).

Maintenance Rituximab is associated with improved clinical outcome in rituximab naïve patients with Waldenstrom Macroglobulinaemia who respond to a rituximab-containing regimen.

This study examined the outcome of 248 Waldenstrom macroglobulinaemia (WM) rituximab-naïve patients who responded to a rituximab-containing regimen. Eighty-six patients (35%) subsequently received maintenance rituximab (M-Rituximab). No differences in baseline characteristics, and post-induction categorical responses between cohorts were observed. The median rituximab infusions during induction was 6 for both cohorts; and 8 over a 2-year period for patients receiving M-Rituximab. Categorical responses improved in 16/162 (10%) of observed, and 36/86 (41·8%) of M-Rituximab patients respectively, following induction therapy (P < 0·0001). Both progression-free (56·3 vs. 28·6 months; P = 0·0001) and overall survival (Not reached versus 116 months; P = 0·0095) were longer in patients who received M-Rituximab. Improved progression-free survival was evident despite previous treatment status, induction with rituximab alone or in combination therapy (P ≤ 0·0001). Best serum IgM response was lower (P < 0·0001), and haematocrit higher (P = 0·001) for patients receiving M-Rituximab. Among patients receiving M-Rituximab, an increased number of infectious events were observed, but were mainly ≤ grade 2 (P = 0·008). The findings of this observational study suggest improved clinical outcomes following M-Rituximab in WM patients who respond to induction with a rituximab-containing regimen. Prospective studies aimed at clarifying the role of M-Rituximab therapy in WM patients are needed to confirm these findings.

Attainment of complete/very good partial response following rituximab-based therapy is an important determinant to progression-free survival, and is impacted by polymorphisms in FCGR3A in Waldenstrom macroglobulinaemia.

The incorporation of rituximab into various regimens has improved depth of response in Waldenstrom macroglobulinaemia (WM), though the impact of achieving better responses remains to be determined. We examined response depth on progression-free survival (PFS) in 159 rituximab-naïve WM patients who received rituximab-based therapy. The median follow-up was 33·5 months, and categorical responses were as follows: complete response (CR, 8·8%); very good partial response (VGPR, 13·2%); partial response (50%); minor response (18·9%); Non-Responders (8·8%). Sequencing for polymorphic variants of FCGR2A, FCGR2B, and FCGR3A was performed, and impact on response depth determined. Achievement of better categorical responses was incrementally associated with improved PFS (P < 0·0001). No separation was observed between CR and VGPR, and attainment of at least a VGPR was associated with improved time-to-progression. Neither age, serum IgM, haematocrit, platelet count, serum ß(2) microglobulin, WM International Prognostic Scoring System score, and treatment group predicted for CR/VGPR. Polymorphisms at FCGR3A-48 and -158 were associated with improved categorical responses, particularly attainment of CR/VGPR (P ≤ 0·03). The attainment of CR/VGPR was associated with significantly longer PFS in rituximab-naïve WM patients undergoing rituximab-based therapy, and was predicted by polymorphisms in FCGR3A.

IgA and IgG hypogammaglobulinemia in Waldenström's macroglobulinemia.

BACKGROUND: Hypogammaglobulinemia is common in Waldenström's macroglobulinemia. The etiology of this finding remains unclear, but it has been speculated to be based on tumor-induced suppression of the 'uninvolved' immunoglobulin production DESIGN AND METHODS: We evaluated the incidence of IgA and IgG hypogammaglobulinemia in 207 untreated patients with Waldenström's macroglobulinemia and investigated the associated clinicopathological findings and impact of therapy. We also sequenced eight genes (AICDA, BTK, CD40, CD154, NEMO, TACI, SH2D1A, UNG) implicated in immunoglobulin deficiency in 19 Waldenström's macroglobulinemia patients with IgA and/or IgG hypogammaglobulinemia. RESULTS: At baseline 63.3%, 58.0% and 49.3% of the 207 patients had abnormally low serum levels of IgA, IgG, or both. No association between IgA and IgG hypogammaglobulinemia and disease burden, serum IgM levels, beta(2)-microglobulin, International Prognostic Scoring System score, or incidence of recurrent infections was observed, although the presence of adenopathy and/or splenomegaly was associated with a lower incidence of hypogammaglobulinemia. Lower IgA and IgG levels were associated with disease progression in patients managed with a 'watch and wait' strategy. IgA and/or IgG levels remained abnormally low despite response to treatment, including complete remissions. A missense mutation in the highly conserved catalytic site of UNG was observed in a patient with hypogammaglobulinemia, warranting further study of this pathway in Waldenström's macroglobulinemia. CONCLUSIONS: IgA and IgG hypogammaglobulinemia is common in Waldenström's macroglobulinemia and persists despite therapeutic intervention and response. IgA and IgG hypogammaglobulinemia does not predict the risk of recurrent infections in patients with Waldenström's macroglobulinemia, although lower levels of serum IgA and IgG are associated with disease progression in Waldenström's macroglobulinemia patients being managed with a 'watch and wait' strategy.

Comparative outcomes following CP-R, CVP-R, and CHOP-R in Waldenström's macroglobulinemia.

Since the adoption of rituximab, the importance of doxorubicin and vincristine as treatment components remains to be clarified in Waldenström's macroglobulinemia (WM). We therefore examined the outcomes of symptomatic patients with WM who received CHOP-R (cyclophosphamide/doxorubicin/vincristine/prednisone plus rituximab; n = 23), CVP-R (cyclophosphamide/vincristine/ prednisone plus rituximab; n = 16), or CP-R (cyclophosphamide/prednisone plus rituximab; n = 19) at our institution. Baseline characteristics for all 3 cohorts were similar for age, previous therapies, bone marrow involvement, hematocrit, platelet count, and serum beta2-microglobulin, though serum immunoglobulin M levels were higher in patients treated with CHOP-R (P < or= .015). The overall response rates (ORR) and complete response (CR) rates to therapy were as follows: CHOP-R (ORR, 96%; CR, 17%); CVP-R (ORR 88%; CR 12%); CP-R (ORR, 95%; CR, 0%); P = not significant. Adverse events attributed to therapy showed a higher incidence for neutropenic fever and treatment-related neuropathy for CHOP-R and CVP-R versus CPR (P < .03). The results of this study demonstrate comparable responses among patients with WM receiving CHOP-R, CVP-R, or CP-R, though a significantly higher incidence of treatment-related neuropathy and febrile neutropenia was observed among patients treated with CVP-R and CHOP-R versus CP-R. The use of CP-R might provide analogous treatment responses to more intense cyclophosphamide-based regimens while minimizing treatment-related complications in patients with WM.

A controlled trial of web-based diabetes disease management: the MGH diabetes primary care improvement project.

OBJECTIVE: To test effects of a web-based decision support tool, the diabetes Disease Management Application (DMA), developed to improve evidence-based management of type 2 diabetes. RESEARCH DESIGN AND METHODS: We conducted a group randomized controlled trial of 12 intervention and 14 control staff providers and 307 intervention and 291 control patients with type 2 diabetes in a hospital-based internal medicine clinic. Providers were randomly assigned from May 1998 through April 1999 to have access to the DMA (intervention) or not to have access (control). The DMA displays interactive patient-specific clinical data, treatment advice, and links to other web-based care resources. We compared patients in the intervention and control groups for changes in processes and outcomes of care from the year preceding the study through the year of the study by intention-to-treat analysis. RESULTS: The DMA was used for 42% of scheduled patient visits. The number of HbA(1c) tests obtained per year increased significantly in the intervention group (+0.3 tests/year) compared with the control group (-0.04 tests/year, P = 0.008), as did the number of LDL cholesterol tests (intervention, +0.2 tests/year; control, +0.01 tests/year; P = 0.02) and the proportions of patients undergoing at least one foot examination per year (intervention, +9.8%; control, -0.7%; P = 0.003). Levels of HbA(1c) decreased by 0.2 in the intervention group and increased by 0.1 in the control group (P = 0.09); proportions of patients with LDL cholesterol levels <130 mg/dl increased by 20.3% in the intervention group and 10.5% in the control group (P = 0.5). CONCLUSIONS: Web-based patient-specific decision support has the potential to improve evidence-based parameters of diabetes care.

Comparison of hyperglycemia, hypertension, and hypercholesterolemia management in patients with type 2 diabetes.

PURPOSE: Cardiovascular disease is the leading cause of death in patients with type 2 diabetes. We compared hyperglycemia management with the management of the cardiovascular disease risk factors hypertension and hypercholesterolemia in a cohort of type 2 diabetes patients. SUBJECTS AND METHODS: We randomly selected 601 patients with type 2 diabetes seen at the outpatient practices of an academic medical center and assessed the care they received during an 18-month period. We compared proportions of patients who had hemoglobin A(1c) (HbA(1c)) levels, blood pressure, or total cholesterol levels measured; who had been prescribed any drug therapy if HbA(1c) levels, systolic blood pressure, or low-density lipoprotein (LDL) cholesterol levels exceeded recommended treatment goals; and who had been prescribed greater-than-starting-dose therapy if these values were above those of treatment goals. RESULTS: Patients were less likely to have cholesterol levels (76%, n = 455) measured than HbA(1c) (92%, n = 552) levels or blood pressure (99%, n = 595; P <0.0001 for either comparison). The proportion of patients that received any drug therapy was greater for above-goal HbA(1c) (92%, n = 348) than for above-goal systolic blood pressure (78%, n = 274) or LDL cholesterol (38%, n = 82; P <0.0001 for each comparison). Similarly, patients whose HbA(1c) levels were above the treatment goal (80%, n = 302) were more likely to receive greater-than-starting-dose therapy, compared with those who had above-goal systolic blood pressure (62%, n = 218) and LDL cholesterol levels (13%, n = 28; P <0.0001). CONCLUSION: In this cohort, hypercholesterolemia and hypertension were managed less aggressively than was hyperglycemia. Given the prevalence of cardiovascular disease in patients with type 2 diabetes, increased screening for hypercholesterolemia and more aggressive drug therapy for hypercholesterolemia and hypertension are needed.

Patients with Waldenström macroglobulinemia commonly present with iron deficiency and those with severely depressed transferrin saturation levels show response to parenteral iron administration.

Anemia often prompts therapy in Waldenström macroglobulinemia (WM), although is not fully explained by bone marrow disease involvement in many patients. Hepcidin regulates gut absorption and distribution of iron and is elevated and associated with anemia in WM. Since hepcidin evaluation remains experimental, we initiated an American Board of Internal Medicine (ABIM) practice improvement project to determine baseline transferrin saturation (TSAT) levels in untreated anemic patients with WM. Among 108 patients with WM evaluated, 56 (52%) had a TSAT level ≤ 20%, which included 25 (23%) patients with severely depressed TSAT levels (≤ 10%). Sixteen patients with TSAT levels ≤ 10% received parenteral iron, and 14 of these patients showed improved hematocrit values (28.75% to 32.75%; P < .0001), mean corpuscular volume (MCV) (84.7 to 89.9; P = .006), and TSAT levels (8.1% to 21.2%; P < .0001). Anemia in 8 of these patients was previously refractory to oral iron therapy. Routine screening of iron saturation levels may therefore identify patients with WM and severe iron deficiency who may be candidates for parenteral iron therapy.

Bridging the gap: a descriptive study of knowledge and skill needs in the first year of oncology nurse practitioner practice.

PURPOSE/OBJECTIVES: To identify the knowledge and skill needs of oncology nurse practitioners (ONPs) as they enter cancer care practice, and to identify necessary educational resources. DESIGN: Cross-sectional, descriptive. SETTING: A national e-mail survey. SAMPLE: 610 self-described ONPs from the Oncology Nursing Society's database. METHODS: The project team developed a 28-item electronic survey. The survey was randomly distributed via e-mail. MAIN RESEARCH VARIABLES: ONPs' feelings of preparedness in the first year of ONP practice. FINDINGS: In the first year of practice, 90% of ONPs rated themselves as prepared or very prepared in obtaining patient history, performing physical examination, and documenting findings. ONPs rated themselves as not at all or somewhat prepared in clinical issues of chemotherapy/biotherapy competency (n = 81, 78%), recognizing and managing oncologic emergencies, (n = 77, 70%), and recognizing and managing drug toxicities (n = 63, 61%). The primary source of oncology education for ONPs new to practice was almost exclusively the collaborating or supervising physician (n = 84, 81%). CONCLUSIONS: Specific knowledge and skills, such as information about chemotherapy, oncologic emergencies, and side effects of therapy, are needed before an ONP enters a cancer care practice. IMPLICATIONS FOR NURSING: Cancer-specific education should be made available to new ONPs as they begin independent practice.

Familial disease predisposition impacts treatment outcome in patients with Waldenström macroglobulinemia.

UNLABELLED: Familial disease is common in Waldenström macroglobulinemia (WM). We examined the impact of familial disease status on treatment outcome in WM and observed that familial disease was associated with inferior outcomes. However patients with familial WM receiving a bortezomib-containing regimen showed improved treatment outcomes vs. those receiving non­bortezomib-containing regimens. Bortezomib-containing regimens may therefore represent a more optimal treatment approach for patients with familial WM. BACKGROUND: We examined the impact of familial predisposition on treatment outcome in 135 patients with Waldenström macroglobulinemia (WM), 26.7% of whom had first- or second-degree relatives with a B-cell lymphoproliferative disorder. PATIENTS AND METHODS: All patients were rituximab naive and received a rituximab-containing regimen. There were no significant differences in baseline characteristics between cohorts. RESULTS: Overall response (93.9% vs. 75.0%; P = .029) and complete response/very good partial response (CR/VGPR) (23.2% vs. 16.7%; P < .0001), time to progression (TTP) (45.5 vs. 21 months; P = .015) and time to next therapy (TTNT) (50.0 vs. 33.0 months; P = .024) favored patients with sporadic WM. By multivariate analysis, familial predisposition was an independent marker for disease progression (hazard ratio, 0.554). Patients with familial but not sporadic disease exhibited better responses, including CR/VGPR attainment (P = .0006) and a trend for longer progression-free survival (> 33 vs. 20.6 months; P = .08), with bortezomib-containing therapy. CONCLUSION: The findings convey that familial predisposition is an important determinant of treatment outcome in WM. Prospective studies to confirm these observations are needed.

Family history of non-hematologic cancers among Waldenstrom macroglobulinemia patients: a preliminary study.

BACKGROUND: Little is known about the epidemiology and etiology of Waldenstrom macroglobulinemia (WM). Despite several studies of the relation between family history and B-cell disorders and WM, family history of non-hematologic cancers has not been systematically investigated. We thus examined associations of family history of breast, colorectal, lung, ovarian, and prostate cancers with WM. METHODS: All probands aged 20-79 years with bone marrow biopsy-confirmed diagnosis of WM between May 1, 1999 and January 1, 2010 at the Bing Center for Waldenstrom Macroglobulinemia were eligible for inclusion in our analysis. We reviewed medical records for eligible probands to determine family history of cancer (defined as a cancer diagnosis for ≥1 first-degree relative(s) of the proband). Using expected values constructed from the United States National Health Interview Survey, we estimated age- and race-standardized rate ratios (RRs) for family history of breast, colorectal, lung, ovarian, and prostate cancers by WM subtype. RESULTS: Family history of prostate cancer had the largest overall rate ratio (RR=1.4, 95% confidence limits [CL]: 1.1, 1.7), and among sporadic cases, family history of prostate and breast cancer had the largest rate ratios (prostate: RR=1.3, 95% CL: 1.1, 1.7; breast: RR=1.3, 95% CL: 1.2, 1.6). CONCLUSION: Our study suggests that it may be worthwhile to pursue these associations in a case-control study with uniform selection and data collection for cases and controls, and at least some record-based information on family history.

Bendamustine therapy in patients with relapsed or refractory Waldenström's macroglobulinemia.

We report the treatment outcome for 30 relapsed/refractory Waldenström's macroglobulinemia (WM) patients following bendamustine-containing therapy. Treatment consisted of bendamustine (90 mg/m2 I.V. on days 1, 2) and rituximab (375 mg/m2 I.V. on either day 1 or 2) for 24 patients. Six rituximab-intolerant patients received bendamustine alone (n=4) or with ofatumumab (1000 mg I.V. on day 1; n=2). Each cycle was 4 weeks, and median number of treatment cycles was 5. At best response, median serum IgM declined from 3980 to 698 mg/dL (P<.0001), and hematocrit rose from 31.9% to 36.6% (P=.0002). Overall response rate was 83.3%, with 5 VGPR and 20 PR. The median estimated progression-free survival for all patients was 13.2 months. Overall therapy was well tolerated. Prolonged myelosuppression was more common in patients who received prior nucleoside analogues. Bendamustine is active and produces durable responses in previously treated WM, both as monotherapy and with CD20-directed monoclonal antibodies.

Associated malignancies in patients with Waldenström's macroglobulinemia and their kin.

We examined the incidence of other malignancies in 924 Waldenström's Macroglobulinemia (WM) patients and their kin. A total of 225 (24.3%) patients had ≥1 additional malignancy, with 63% predating the WM diagnosis. The most common gender-adjusted malignancies were prostate (9.4%), breast (8.0%), non-melanoma skin (7.1%), hematologic (2.8%), melanoma (2.2%), lung (1.4%) and thyroid 1.1%). Among hematologic malignancies, all 13 cases of diffuse large B-cell lymphoma and 4 cases of acute myelogenous leukemia were diagnosed after WM, and were therapy-related. Familial WM subgroup analysis showed a higher incidence of prostate cancer (P=.046) in sporadic WM patients, while patients with familial WM had a higher incidence of lung cancer (P=.0043). An increased incidence of myeloid leukemias (P<.0001) was reported among kin of familial WM patients. These data reveal specific cancer associations with WM, and provide a basis for exploratory studies aimed at delineating a common genetic basis. Additionally, these studies suggest specific cancer clustering based on familial predisposition to WM.

Hepcidin is produced by lymphoplasmacytic cells and is associated with anemia in Waldenström's macroglobulinemia.

Waldenström's macroglobulinemia (WM) patients often present with anemia as their primary disease manifestation that may be related to hepcidin, an important regulator of iron homeostasis. We therefore determined hepcidin levels in 53 WM patients, and 20 age-matched healthy patient donors by hepcidin-25 ELISA. Serum hepcidin levels were elevated in WM patients versus healthy patients (P=.04), and correlated with BM disease involvement (P=.004), beta-2-microglobulin levels (P=.029), and inversely with hemoglobin (P=.05). No correlation with serum iron indices was observed, though in patients with high hepcidin levels, increased iron deposition in bone marrow macrophages was observed. Importantly, hepcidin transcripts and protein were produced by primary WM cells. Hepcidin levels correlated with serum IL-6 (P<.001) and C-Reactive Protein (P=.033) levels. The results of this study implicate hepcidin as a contributor to anemia in WM, and suggest that an iron re-utilization defect accompanies hepcidin overproduction leading to its sequestration in WM patients.

Histone deacetylase inhibitors demonstrate significant preclinical activity as single agents, and in combination with bortezomib in Waldenström's macroglobulinemia.

We studied the role of histone deacetylase inhibitors in Waldenstrom's macroglobulinemia (WM). Gene expression profiling of bone marrow CD19+ cells from 30 patients and 10 healthy donors showed overexpression of HDAC4, HDAC9, and Sirt5, with validation of HDAC9 overexpression by q-PCR in primary and BCWM.1 cells. Suberoylanilide hydroxamic acid, trichostatin A, panobinostat, and sirtinol demonstrated dose-dependent killing of BCWM.1 cells. TSA showed the greatest potency with IC50 of 70 nM. Importantly, HDAC9 activity was decreased following TSA treatment suggesting an essential role for this HDAC in WM therapy. The combination of bortezomib plus HDAC inhibitors resulted in at least additive tumor cell killing in BCWM.1 cells. TSA and bortezomib-induced apoptosis depended on a similar set of caspase activation, whereas their effect on cell cycle regulators was distinctly different. These results provided a framework for examining HDAC inhibitors as monotherapy, as well as combination therapy with bortezomib in WM.

Primary therapy of Waldenström macroglobulinemia with bortezomib, dexamethasone, and rituximab: WMCTG clinical trial 05-180.

PURPOSE: We examined the activity of bortezomib, dexamethasone, and rituximab (BDR) in patients with symptomatic, untreated Waldenström macroglobulinemia (WM). PATIENTS AND METHODS: A cycle of therapy consisted of bortezomib 1.3 mg/m(2) intravenously; dexamethasone 40 mg on days 1, 4, 8, and 11; and rituximab 375 mg/m(2) on day 11. Patients received four consecutive cycles for induction therapy and then four more cycles, each given 3 months apart, for maintenance therapy. Twenty-three patients received a median of seven cycles of treatment. RESULTS: Median bone marrow disease involvement declined from 55% to 10% (P = .0004), serum immunoglobulin M levels declined from 4,830 to 1,115 mg/dL (P < .0001), and hematocrit increased from 29.8% to 38.2% (P = .0002) at best response. The overall response rates and major response rates were 96% and 83% with three complete responses, two near complete responses, three very good partial responses, 11 partial responses, and three minor responses. Responses occurred at a median of 1.4 months. With a median follow-up of 22.8 months, 18 of 23 patients remained free of disease progression. Peripheral neuropathy was the most common toxicity, and it resolved to grade < or = 1 in 13 of 16 patients at a median of 6.0 months. Four of the first seven treated patients developed herpes zoster, resulting in the institution of prophylactic antiviral therapy. CONCLUSION: The results demonstrate that BDR produces rapid and durable responses, along with high rates of response and complete remissions in WM. Herpes zoster prophylaxis is necessary with BDR, and reversible peripheral neuropathy was the most common toxicity leading to premature discontinuation of bortezomib in 61% of patients. Exploration of alternative schedules for bortezomib administration that includes weekly dosing should be pursued.

Health care resource utilization associated with a diabetes center and a general medicine clinic.

OBJECTIVE: Studies have proposed that the features of diabetes clinics may decrease hospital utilization and costs by reducing complications and providing more efficient outpatient care. We compared the health care utilization associated with a diabetes center (DC) and a general medicine clinic (GMC). DESIGN: Retrospective cohort study. SETTING: An urban academic medical center. PATIENTS/PARTICIPANTS: Type 2 diabetes patients (N = 601) under care in a DC and GMC before March 1996. MEASUREMENTS AND MAIN RESULTS: We compared baseline patient characteristics and outpatient care for the period of March 1996 to August 1997. Using administrative data from March 1996 to October 2000, we compared the probability of a hospitalization, length of stay, costs of hospitalizations, the probability of an emergency room visit, and costs of emergency room visits. Diabetes center patients had a longer mean duration of diabetes (12 years vs 6 years, P <.01), more baseline microvascular disease (65% vs 44%, P <.01), and higher baseline glucose levels (hemoglobin A1c 8.6% vs 7.9%, P <.01) than GMC patients. Diabetes center patients received more intensive outpatient care directed toward glucose monitoring and control. In all crude and adjusted analyses of hospitalizations and emergency room visits, we found no statistically significant differences for inpatient utilization or cost outcomes comparing clinic populations. CONCLUSIONS: Diabetes center attendance did not have a definitive positive or negative impact on inpatient resource utilization over a 4-year period. However, DC patients had more severe diabetes but no greater hospital utilization compared with GMC patients. Clear demonstration of the clinical and financial benefits of features of diabetes centers will require long-term controlled trials of interventions that promote comprehensive diabetes care, including cardiovascular prevention.