Reccurent and prolonged panctopenia with rituximab therapy

e19550

Background: Rituximab, a monoclonal antibodies designed against a CD20 glycoprotein expressing lymphocytes. This drug has been implemented in the treatment of B cell lymphoproliferative disorders as well as non-neoplastic disease such as autoimmune thrombocytopenia, immune hemolytic anemia and other disorders related to overexpression of antibodies against the host. Rituximab doccumented side effects such as allergic infusion reaction, tumor lysis syndrome and lymphodepletion are frequently seen. However, transient neutropenia is less common. This abstract reports recurrent and long standing pancytopenia that had adverse deadly sequellae. Methods: This abstract report five cases of recurrent and prolonged pancytopenia not related to concomittant cytotoxic effect of chemotherapy. It is a retrospective analysis of treating three hundred patients in the last six years. Results: Five patient sustained recurrent prolonged pancytopenia post rituximab therapy. Two females (age 33 and 55) and three males (age 40, 50 and sixty). Mean age is 46 years. All developed sever neutropenia as well as pancytopenia. One patient, a female( age 33) had rheumatoid arthritis and the rest had non hodgekin's lymphoma. This female patient died due to sever long standing neutropenia/pancytopenia with pneumonia. All patients had bone marrow biopsy for evaluation. Decreased cellularity below 40% seen. None of the patients with non hodgkin's lymphoma had bone marrow involvement. The four patients are still in remmission. Conclusions: In conclusion the etiology of sustained neutropenia and pancytopenia is not understood. Whether, bone marrow aplasia, dysplasia or other immune mechanism exist need more study.

No significant financial relationships to disclose.

Characteristics of Hodgkin lymphoma in Hispanics compared to other ethnic groups

18510

Background: There is scant literature on the characteristics of Hodgkin’s disease in Hispanics. We studied the characteristics of this disease in Hispanics compared to other ethnic-racial groups in our large multiethnic Hodgkin’s disease caseload. Methods: A retrospective analysis of all the Hodgkin’s disease cases diagnosed between 2003 and 2006 was undertaken, using Fisher exact test. Results: Of 289 cases of lymphoma diagnosed, 65 (23%) were Hodgkin’s disease compared to SEER data of 11%; Hispanics 40%, African Americans (AA) 41%, Caucasians 19%. Median age at diagnosis: Hispanics 26, AA 27, Caucasians 38. Among the AA: 85% were men 15% women, Hispanics: 58% men 42% women, Caucasians: 33% men, 67% women (p value 0.004). Histological subtypes: Nodular sclerosis 82 % (58): AA 45%, Hispanics 34%, Caucasians 21%; Mixed cellularity 21% (8): Hispanics 75%, AA 12.5%, Caucasians12.5% (p value 0.079). Among Hispanics 62% were clinical stage 1 or 2, 38% stage 3 or 4; Caucasians 75% stage 1 or 2, 25% stage 3 or 4; AA 33% stage 1 or 2 and 66% stage 3 or 4 (p value 0.029). Among the 16 patients with limited stage disease 50% were Hispanics, 25% Caucasians and 25% AA. Of the 49 patients with advanced stage disease, 70% of the Hispanics had IPS Score 0–3, 30% had Score 4–7. Among the AA, 70% had IPS Score 0–3, 30% Score 4–7, while 33% of the Caucasians had IPS Score 0–3, 67% had Score 4–7 (p value 0.077). Conclusions: Mixed cellularity subtype is more common in the Hispanics while the nodular sclerosis subtype is relatively common in African Americans. Hispanics had early clinical and limited stage disease at diagnosis. Among the patients with advance stage disease, Caucasians had a higher IPS Score than the Hispanics. The clinical relevance of these observations remains to be determined with further studies.

No significant financial relationships to disclose.

Cetuximab-induced thrombotic thrombocytopenic purpura in a patient with a resected squamous cell carcinoma of the lip

14155

Background: Chemotherapy-associated thrombotic thrombocytopenic purpura (TTP) has been described in the literature. However Cetuximab, a monoclonal antibody targeted to the EGF receptor, has not yet been associated with TTP. We report a case of an 85 year old woman with a resected squamous cell carcinoma of the lip who developed TTP after receiving cetuximab. Methods: A day after receiving Cetuximab, as part of an adjuvant concurrent cetuximab-radiotherapy regimen, the patient presented with gingival bleeding and confusion without fever but with significant petechial rash and jaundice.. Hemoglobin level was 6.9 g/dL WBC 3.9 k/uL Platelet count 4 k/uL Lactate dehydrogenase 1350 U/L Indirect bilirubin 3.8 mg/dL Haptoglobulin < 6 mg/dL Reticulocyte count 4.4 %. Serum creatinine, ANA, coagulation profile, coomb‘s test were normal. Peripheral blood smear showed 3+ schistocytes. TTP was diagnosed and daily plasmapheresis was initiated. TTP resolved after 8 sessions of plasmapheresis with platelet count increasing to 446 k/uL and sustained. Results: Competing etiologies for our patient’s TTP were cancer and cetuximab. Most reported cases of cancer-associated TTP occurred in patients with metastatic adenocarcinoma. Our patient had a non-metastatic resected squamous cell carcinoma with only residual microscopic disease. Since TTP developed closely following cetuximab administration and resolved with plasmapheresis after stopping cetuximab, we concluded that its development was most likely secondary to cetuximab or to antibody developed to it. Possible mechanisms for cetuximab-induced TTP are direct endothelial damage by cetuximab leading to platelet activation and aggregation or inhibition of metalloproteinase, resulting in accumulation of Ultra-large VWF multimers. Conclusions: Targeted-therapy is emerging as an effective treatment modality in medical-oncology. Further clinical experience is needed to ascertain the full extent of potentially fatal adverse events. To our knowledge this is the first case of cetuximab-induced TTP.

No significant financial relationships to disclose.

Single institutional experience with rituximab in the treatment of B cell lymphoproliferative malignancies and autoimmune disorders

14150

Background: This is a retrospective analysis of usage of rituximab( Rituxan) a monoclonal antibodies against CD20 expressing B lymphocytes.The duration of period studied is from December first,2004 to July first,2006.This involved one single institution, John Stroger hospital of Cook County,chicago. Methods: A total of two hundred and thirty 230 treatment courses recorded.This involved a total of 208 patients.Some patients treated with more than one course in combination with different chemotheraputic agents. Results: . A total of 208 patients received Rituxan. Median number of doses is 8 (range 1–18). This include 92 patients with Diffuse large B-cell NHL, six patients with Burkitt’s lymphoma, thirty six patients with low grade NHL, three patients with mantle cell lymphoma, three patients with orbital lymphoma, three patient with AIDS related NHL, twenty seven patients with chronic lymphocytic leukemia CLL, ten patients with MALT/Gastric lymphoma, ten patients with ITP and 7 patient with warm autoimmune hemolysis, 7 patients given Rituxan as part of Rheumatoid Arthritis treatment. The complete response rate CR, near CR, partial response improved with adding Rituxan to 85% in Diffuse large grade Bcell lymphoma, one third high IPI score. Only 15% were refractory or relapsed after response. In low grade Bcell NHL 1/3 of patients received multiple prior treatments and the response rate were improved and disease progression was delayed. Most patients are of younger mean age 55 range (19–80).One third of patients recieved maintenace rituxan .Transfusion reaction occurred in less than 10%, severe leucopenia 3%, GI perforation in one patient, focal leukoencephalopathy PML in one with CNS involvement, tumor lysis syndrome occured in three patients, severe mucocutaneous reaction occured in one patient.One patient with RA and warm immune hemolysis died with sever pancytopenia after two months from recieving four doses. . Conclusions: This is a single institution experience where 60 percents are african american. This also show that Rituxan usage has became a standard therapy in Bcell lymphoproliferative malignancies.The improvement in response rate and progression free survival match other published phase III multicentered studies.

No significant financial relationships to disclose.

Race as a risk factor for developing osteonecrosis of the jaw after long term bisphosphonate therapy in patients with metastatic breast cancer

596

Background: Association between osteonecrosis of the jaw (ONJ) and bisphosphonate treatment has been increasingly reported in the literature. Methods: This is a retrospective review of a single institution’s experience with patients diagnosed with bone metastasis secondary to breast cancer, who developed ONJ while treated with bisphosphonates (Zoledronic acid - Zometa; Pamidronate - Aredia), between 1.1.2001 and 10.30.2005. Presentation, age, race, and outcome were reviewed. Logistic Regression was used to test for statistical significance. Results: 161 patients with bone metastasis secondary to breast cancer treated with bisphosphonates were reviewed (82 African American, 29 Caucasians, 26 Hispanic, 15 Asian and 9 others.). ONJ developed in 6 (3.7%) patients, 5 of which were Caucasians. Logistic regression adjusting for dose shows that the odds ratio for developing ONJ comparing Caucasians with non-Caucasians is 45.7 (p=0.016). Age did not impact occurrence of ONJ. All 6 patients developed ONJ after a minimum of 31 months of treatment. Two patients had a history of previous tooth extraction. In four other patients, ONJ appeared spontaneously. One patient, who presented with an abscess, developed sepsis which resulted in the patient’s death. Two patients were treated with debridement and antibiotics and their lesions healed. Three other patients ended up suffering from a chronically exposed bone. Conclusion: ONJ is a serious complication of bisphosphonate therapy and it affected a significant proportion of our patients. Our data suggests that Caucasians may be more susceptible. Since sample size is small, determining if race is a risk factor for the development of ONJ, while on bisphosphonate therapy, will require further investigation.

No significant financial relationships to disclose.

High remission rate in acute myeloblastic leukemia with only two days of chemotherapy

Twenty five patients with AML who had neither a history of toxic exposure or myelodysplasia were treated with a remission induction regimen consisting of two pulses of chemotherapy separated by 96 hrs. Each pulse consisted of cytarabine 2gm/m(2) (at t=0 and t=12 hrs) with mitoxantrone [30mg/m(2) ] administered immediately after the second cytarabine administration. Amifostine was administered three times a week [on Monday, Wednesday, and Friday] until the outcome of therapy was known. This regimen induced complete remissions in 15 of 17 patients less than 70 years of age and in 5 of 8 patients older than 70 years.

Effectiveness of interferon-alfa and mid-cycle chemotherapy added to an anthracycline-based regimen in the treatment of aggressive non-Hodgkin's lymphoma

Interferon-alfa in combination with cytotoxic chemotherapy has been shown to be effective in treating certain types of non-Hodgkin's lymphoma (NHL) (1). However, there is no published data on upfront induction treatment of aggressive NHL with IFN-alfa containing regimens. Studies have also shown that one can overcome regrowth resistance by administering mid-cycle agents which slow tumor proliferation between courses of cytotoxic therapy (2). Based on this, we treated 32 consecutive patients between 1/93 and 9/96 with a regimen containing cyclophosphamide 750 mg/m2, mitoxantrone 12 mg/m2, and teniposide 60 mg/m2 IV on day 1 with prednisone 100 mg PO given on days 1-5. On day 15, patients received vincristine 1.4 mg/m2 (2 mg max.) and bleomycin 10 units/m2 IV. Interferon-alfa-2b 5x10(6) units/m2 SQ was administered on days 22-26. The median age was 55 (range 26-83), M:F ratio was 2.5:1, and the median International Prognostic Index was 2. 38% of patients had stages I-II and 62% had stages III-IV disease. Fifty-nine percent of the patients achieved a complete response, 22% a partial response, and 19% had progressive disease. The overall survival (OS) was 81% and the progression free survival (PFS) was 56% at 4.3 years. There were no severe (grade IV) hematologic, flu-like, GI and infectious toxicities from IFN-alpha. Leukopenia was the main severe toxicity related to the chemotherapy regimen (days 1-15), but not IFN-alpha. Severe infection secondary to the chemotherapy regimen occurred in one patient. Interferon-alfa-2b and mid-cycle chemotherapy added to an anthracycline based regimen is effective induction treatment for patients with aggressive NHL. The OS and PFS using this regimen, based on regrowth resistance, appears to be at least as or more effective than CHOP therapy for this group of patients. Severe toxicities were rare.

Poor prognosis acute myelogenous leukemia: 1 - response to treatment with high dose cytarabine/mitoxantrone/ethyol @ (Amifostine)

Twenty patients with poor prognosis AML and four patients in the blastic phase of a myeloproliferative disorder were treated with two 'pulses' of therapy each consisting of two doses of high dose araC (separated by 12 h) followed by a single dose of mitoxantrone. The pulses were separated by 96 h. Amifostine was then administered tiw. The median age of the population was 68 years with 88% of patients having had either a prior MDS, MPD or toxic exposure. The acute leukemia of 58% of patients either entered a CR or reverted to preleukemic state. For patients under 70 years of age, treatment produced 62% CRs with a leukemia free decision marrow in 77%. For patients over 70 years the CR rate was 27% with 36% of patients having a leukemia free decision marrow.

Tumor necrosis factor modulates CD 20 expression on cells from chronic lymphocytic leukemia: a new role for TNF alpha?

Tumor necrosis factor alpha (TNF alpha) is a pleiotropic cytokine that is constitutively produced by leukemic cells in B Chronic Lymphocytic Leukemia (B-CLL). It has been shown to have autocrine and paracrine functions in normal B cells and in B lymphoproliferative diseases. This study was conducted to determine the effect of TNF alpha (in vitro) on CD20 expression on cells from patients with B-CLL. Currently, anti-CD20 monoclonal antibody therapy is becoming a second line treatment in the management of B cell disorders like low-grade non-Hodgkin's lymphoma (NHL) and B-CLL. Our results demonstrate amply that very low doses of TNF alpha (0. 0125 ng/ml) can be used to significantly increase CD20 expression on cells from patients of B-CLL as evidenced by increases in both percentage positivity and mean fluorescence intensity. The upregulation is evident as early as 24 hours and is maintained for up to 72 hours. We propose that the upregulation is a direct result of in vitro differentiation stimulated by TNF alpha. The results presented can be exploited in the designing of priming protocols prior to antibody therapy and this is discussed.

Effect of interferon-alpha on CD20 antigen expression of B-cell chronic lymphocytic leukemia

Chimeric CD20 monoclonal antibody as alternative therapy in relapsed low-grade non-Hodgkin's lymphoma (NHL) has produced responses in nearly 50% of patients. Augmenting CD20 expression on tumor cells and/or inducing its expression may increase the cell kill and effectiveness of antibody therapy. Peripheral blood lymphocytes from 19 patients with B-cell chronic lymphocytic leukemia (B-CLL) were incubated in vitro in the presence of interferon-alpha (IFN-alpha) (500 U/ml and 1,000 U/ml) for 24 and 72 hours. The effect on CD20 expression was studied by flow cytometry. The differences in the percentage positivity, the mean fluorescence intensity (MFI), and the product of percentage positivity and MFI were used to assess upregulation. There was a significant upregulation of CD20 expression on B cells seen at both concentrations after 24-hour priming (p < 0.01). B-CLL cells cultured for 72 hours in the presence of IFN-alpha also showed upregulation of CD20 expression; however, the degree of upregulation was much lower than that seen at 24 hours. There was no statistically significant increase in CD20 antigen expression on normal lymphocytes following cytokine exposure. These results suggest that IFN-alpha priming may augment the effectiveness of antibody therapy by directly upregulating CD20 antigen expression in addition to its indirect action through effector cells of the host.

Suppression of telomerase activity and cytokine messenger RNA levels in acute myelogenous leukemia cells in vivo in patients by amifostine and interleukin 4

High levels of telomerase activity and high rates of cell proliferation are associated with a poor prognosis in acute myelogenous leukemia. Furthermore, cytokine production by leukemia cells is believed to play an important role in determining the proliferative characteristics of leukemia. The in vivo effects of two noncytotoxic agents on these parameters were determined in 33 acute myelogenous leukemia patients. Three daily doses of interleukin (IL) 4 or a single dose of amifostine reduced telomerase activity in the leukemia marrow cells in 7 of 9 and 11 of 13 patients, respectively. The administration of a single dose of amifostine resulted in a reduction in tumor necrosis factor alpha and IL-6 transcript levels in the marrow cells of 10 of 13 and 12 of 13 patients in which these transcripts were present. The administration of only three doses of IL-4 or a single dose of amifostine has a significant effect on leukemia cell parameters, which are believed to have a significant impact on the in vivo biology of the disease and on its response to remission induction therapy.

Induction of type 1 programmed cell death in U937 cells by the antioxidant, butylated hydroxy-toluene or the free radical spin trap, NTBN

Oxidative stress can initiate programmed cell death and contributes to the patho-physiology of a number of diseases. Low micromolar to millimolar concentrations of various antioxidants or free radical scavengers promote cell growth and reduce cellular suicide induced by several functionally distinct agents, including some known to produce oxidative stress. Severe anoxia or inhibitors of oxidative phosphorylation also initiate programmed cell death. These results seem paradoxical. In order to compare the response of U937 monoblastoid cells to higher concentrations of an antioxidant or a free radical-spin trap, cells were cultured with 20-80 microM concentrations of butylated hydroxy-toluene or with 5 to 60 mM concentrations of the free radical spin trap, N-tertiary butyl phenyl-nitrone. At these concentrations, both agents inhibited cellular proliferation and induced oligosomic DNA, detected by its 'laddering' after electrophoresis on agarose, confirmed by TUNEL (BHT) or flow cytometric (NTBN) evidence of hypodiploid DNA and ultrastructural evidence of a type 1 programmed cell death. The ability of hydroxy-toluenes to oxidize DNA and promote carcinogenesis and whether free radical spin traps could augment or interfere with the response of malignantly transformed cells to chemotherapy or ionizing radiation provide the raison d'etre of these studies.

An in vivo inhibitor of 5-lipoxygenase, MK886, at micromolar concentration induces apoptosis in U937 and CML cells

MK886 (Merck Frosst) is a selective in vivo inhibitor of 5-lipoxygenase, active at nanomolar concentrations. At micromolar concentrations, it inhibited the proliferation of U937 monoblastoid cells and of cultured malignant cells from patients with chronic myelogenous leukemia. These cells became morphologically apoptotic, a form of physiologic cell death. U937 cell apoptosis was assessed by flow cytometry, ultrastructure, DNA laddering and immuno-histology for free 3'OH-DNA. MK886-induced apoptosis developed over time as cells were recruited in concert with reduction in their numbers. Some CML cells exhibited cytoplasmic changes of apoptosis without typical nuclear changes. Under conditions used for measuring Ca2+ with Fura 2, 10 micromolar MK886 increased U937 intracellular Ca2+ 4-fold or more over the 8 minute period of measurement. Since MK886 inhibits the association of arachidonic acid with the 5-lipoxygenase activating protein, altered arachidonic acid metabolism may have contributed to these results.

Selective inhibitors of 5-lipoxygenase reduce CML blast cell proliferation and induce limited differentiation and apoptosis

Inhibitors of the arachidonic acid metabolizing enzyme, 5-lipoxygenase, reduce the rate of proliferation of chronic myelogenous leukemia blast cells. The inhibitory agents studied were ETYA, A63162 and SC41661A. These reagents induced differentiation of cultured chronic myelogenous leukemia cells from blast to promyelocytic morphology. Promyelocytic cells then underwent apoptosis, which was identified by nuclear and cytoplasmic morphological features and by DNA laddering. Proliferation of monoblastoid U937 and myelomonocytic HL60 cell lines, known to contain 5-lipoxygenase and synthesize leukotrienes, was reduced by these inhibitors. U937 cells cultured with ETYA, A63162 or SC41661A for 48 h exhibited apoptosis as assessed by DNA laddering and morphology. Characteristic ultrastructural changes of apoptosis were seen at 120 h. MK886, an inhibitor of 5-lipoxygenase with a mechanism of action distinct from oxidation/reduction reagents, at 20-40 microM also inhibited CML and U937 cell proliferation and induced apoptosis, as shown by DNA laddering and ultrastructure.

Induction of apoptosis in blood cells from a patient with acute myelogenous leukemia by SC41661A, a selective inhibitor of 5-lipoxygenase

Participation of leukotriene products in normal ex vivo hematopoiesis is well established. With increasingly specific inhibitors of lipoxygenases, it becomes possible to more closely define any participation of their biosynthetic products in these events. We cultured chronic myelogenous leukemia cells from the peripheral blood of several patients in blast crisis with three inhibitors of lipoxygenases: ETYA, and the more selective A63162 (Abbott) or SC41661A (Searle). All three agents reduced labelling of DNA with H3 thymidine measured at 4 h and reduced cell numbers by 72 h. An antisense deoxyoligonucleotide to the 5-lipoxygenase mRNA 'start' codon inhibited DNA synthesis at 24 h, as did two control oligonucleotides. Marked nuclear ultrastructural changes characteristic of apoptosis were induced by SC41661A in a subset of cells with the ultrastructure of promyelocytes. Whether this response characterizes a common pattern of this subset of leukemic cells to SC41661A, if damage to mitochondria with reduced function of bcl-2 protooncogene product located at that site might have contributed or some other mechanism was responsible, and if inhibition of 5-lipoxygenase activity was involved, are questions to be decided in the future.