Low-dose interferon alfa-2b in the treatment of hairy cell leukemia

Twenty-two patients with hairy cell leukemia were treated with low-dose interferon alfa-2b (0.2 X 10(6) U/m2 given three times weekly) for 6-12 months. The overall response rate was 54%, with only 18% complete plus partial responses. The therapy had to be terminated early in five of these patients because their progressive disease led to severe cytopenia. Although the toxic effects with this regimen were minimal, the significantly lower response rate and the poorer quality of the responses prohibit its use as initial therapy in hairy cell leukemia.     

Cost-benefit analysis of interferon alfa-2b in treatment of hairy cell leukemia

The clinical benefits as well as the cost benefits of use of recombinant interferon (IFN) alfa-2b instead of conventional chemotherapy (primarily chlorambucil) for progressive hairy cell leukemia were assessed retrospectively on the basis of 12 months of clinical data from 128 patients treated with IFN alfa-2b. Data from 71 matched historical control patients who had received conventional treatment were used for survival analysis. Hematologic response (reversal of cytopenias) was achieved by 18% of the control patients versus 73% of the IFN-treated patients. This response was associated with virtual elimination of the need for transfusions and splenectomy as well as dramatic decreases in the frequency of fatal infections (22.5% vs. 1.6%) and the 12-month mortality rate (28% vs. 3.1%). Direct costs per patient per year for medical care (transfusions, antibiotic treatment, splenectomy, and chemotherapy) of those receiving IFN alfa-2b were 2.8-fold lower than costs for medical care of control patients ($5,027 vs. $14,046). Indirect costs, which reflect the present value of future earnings lost due to premature death, were 13.3-fold lower for IFN-treated patients than for control patients ($4,771 vs. $63,507). Our analysis demonstrates that IFN alfa-2b offers substantial clinical and cost advantages to patients with hairy cell leukemia and that the introduction of this therapy using novel biotechnology furthers the health care community's commitment to cost containment.     

Patient preferences for adjuvant interferon alfa-2b treatment.

PURPOSE: Although trials of adjuvant interferon alfa-2b (IFN alpha-2b) in high-risk melanoma patients suggest improvement in disease-free survival, it is unclear whether treatment offers improvement in overall survival. Widespread use of adjuvant IFN alpha-2b has been tempered by its significant toxicity. To quantify the trade-offs between IFN alpha-2b toxicity and survival, we assessed patient utilities for health states associated with IFN therapy. Utilities are measures of preference for a particular health state on a scale of 0 (death) to 1 (perfect health). PATIENTS AND METHODS: We assessed utilities for health states associated with adjuvant IFN among 107 low-risk melanoma patients using the standard gamble technique. Health states described four IFN alpha-2b toxicity scenarios and the following three posttreatment outcomes: disease-free health and melanoma recurrence (with or without IFN alpha-2b) leading to cancer death. We also asked patients the improvement in 5-year disease-free survival they would require to tolerate IFN. RESULTS: Utilities for melanoma recurrence with or without IFN alpha-2b were significantly lower than utilities for all IFN alpha-2b toxicities but were not significantly different from each other. At least half of the patients were willing to tolerate mild-moderate and severe IFN alpha-2b toxicity for 4% and 10% improvements, respectively, in 5-year disease-free survival. CONCLUSION: On average, patients rate quality of life with melanoma recurrence much lower than even severe IFN alpha-2b toxicity. These results suggest that recurrence-free survival is highly valued by patients. The utilities measured in our study can be applied directly to quality-of-life determinations in clinical trials of adjuvant IFN alpha-2b to measure the net benefit of therapy.     

伊马替尼联合干扰素-α治疗慢性髓细胞性白血病的疗效

目的探讨伊马替尼联合干扰素-α治疗慢性髓细胞性白血病的疗效。方法回顾性分析50例慢性髓细胞性白血病患者的临床资料,分为接受伊马替尼联合干扰素-α治疗的观察组(28例)和接受干扰素-α治疗的对照组(22例),观察治疗后缓解情况、不良反应例数以及生活质量。结果两组患者血液学缓解情况无明显差异,观察组细胞遗传学反应情况明显好于对照组,各类不良反应例数明显少于对照组,KPS评分、躯体功能、心理功能、社会功能、认知功能和总体生活质量评分明显高于对照组。结论伊马替尼联合干扰素-α能够改善治疗的细胞遗传学反应、减少不良反应例数、提高患者生活质量,是行之有效的治疗方式。     

Pegylated recombinant interferon alpha-2b vs recombinant interferon alpha-2b for the initial treatment of chronic-phase chronic myelogenous leukemia: a phase III study.

Recombinant interferon alpha-2b (rIFN-alpha2b) is an effective therapy for chronic-phase chronic myelogenous leukemia (CML). Polyethylene glycol-modified rIFN-alpha2b is a novel formulation with a serum half-life ( approximately 40 h) compatible with once-weekly dosing. This open-label, noninferiority trial randomized 344 newly diagnosed CML patients: 171 received subcutaneous pegylated rIFN-alpha2b (6 microg/kg/week); 173 received rIFN-alpha2b (5 million International Units/m2/day). Primary efficacy end point was the 12-month major cytogenetic response (MCR) rate (<35% Philadelphia chromosome-positive cells). Modified efficacy analysis included all MCRs >12 months, except for patients discontinuing treatment after 6 months and achieving an MCR on other salvage therapy. The MCR rates were 23% for pegylated rIFN-alpha2b vs 28% for rIFN-alpha2b in the primary efficacy analysis and 26 vs 28% in the prospectively modified efficacy analysis. However, a significant imbalance in baseline hematocrit (HCT), a significant predictor of cytogenetic response (P=0.0001), was discovered: 51 (30%) patients treated with pegylated rIFN-alpha2b had low HCT (<33%) vs 33 (19%) rIFN-alpha2b-treated patients. Among patients with HCT >33%, the MCR rate was 33 vs 31%. The adverse event profile of weekly pegylated rIFN-alpha2b was comparable to daily rIFN-alpha2b. Once-weekly pegylated rIFN-alpha2b is an active agent for the treatment of newly diagnosed CML with an efficacy and safety profile similar to daily rIFN-alpha2b, although statistical noninferiority was not demonstrated.     

Leukocyte interferon in the treatment of chronic myelogenous leukemia in second chronic phase

Four patients with Philadelphia chromosome positive CML were treated with 18-42 x 10(6) IU of purified natural leukocyte IFN-alpha per week, after high-dose chemotherapy for blast phase and attainment of 2nd chronic phase. The second blast phase occurred within 3 months in 3 patients, but one patient is still in second chronic phase after 22 months of treatment. Treatment consisted of interferon only during the first year, and interferon in combination with hydroxyurea during the second year. During the second year suppression of the Philadelphia chromosome was seen in one patient, with 20% Philadelphia negative bone marrow metaphases. The toxicity of purified natural leukocyte IFN-alpha was similar to the toxicity of recombinant IFN-alpha. Antibodies to IFN-alpha were not detected in any patient.     

Pegylated interferon alfa-2b as treatment of solid tumors

Conclusions PEG-IFN á-2b is active in patients with metastatic RCC and melanoma and is tolerated well at doses up to 6.0 μg/kg/wk. This trial provides a rationale for further studies using this pegylated cytokine alone or in combination with such agents as interleukin (IL)-2.     

Flow cytometry in hairy cell leukemia before and during interferon alfa-2b therapy

Mononuclear cells from 15 patients with hairy cell leukemia were studied before and during therapy with interferon alfa-2b (IFN) by regular peripheral blood differential counts and flow cytometry, using a panel of monoclonal antibodies (Moab). Seven leukemic phase patients (Group 1) had a mean leukocyte count of 48,870/microliter at entry with a mean absolute hairy cell (HC) count of 40,100/microliter. After 3 months on IFN, both parameters decreased significantly (WBC 3,500/microliter; HC count 130/microliter). In eight patients with a cytopenic form of the disease (Group 2) the mean leukocyte count rose from 2950/microliter to 3890/microliter while the mean absolute HC count decreased from 300/microliter to 120/microliter. The morphologic shifts correlated well with changes in the Moab reaction pattern. In Group 1 the activity of all Moab decreased significantly. In Group 2, only cells expressing Leu 3a and Leu 11a (a marker of natural killer cells) showed a significant shift, the latter increasing from 170/microliter to 360/microliter. This increase in natural killer cell antigen expression was not obvious based on routine morphologic observations alone. We show that flow cytometry may be a useful adjunct in monitoring the response of HCL to therapy. Changes in populations of cells that may be difficult to discriminate on morphologic grounds alone may be observed.     

DNA-flow cytometry studies in blood and marrow cells from chronic myelogenous leukemia patients treated with interferon alpha-2b

Cell cycle distribution in bone marrow and peripheral blood mononucleated cells was studied in patients with chronic myelogenous leukemia (CML) before and during treatment with interferon (IFN) alpha-2b. DNA-flow cytometry with ethidium bromide fluorescence was used. Highly significant differences between mononucleated cells from CML patients and normal controls were seen in peripheral blood but not in bone marrow specimens. Patients achieving hematologic remission during IFN treatment showed a cell cycle distribution in bone marrow cells and peripheral blood cells similar to normal controls.     

Risk factors for severe neuropsychiatric toxicity in patients receiving interferon alfa-2b and low-dose cytarabine for chronic myelogenous leukemia: analysis of Cancer and Leukemia Group B 9013.

PURPOSE: Recombinant interferon alfa-2b (rIFNalpha2b) is a standard therapy for chronic myelogenous leukemia (CML). Severe neuropsychiatric toxicity has been described in patients receiving rIFNalpha2b, although the frequency of and the risk factors for developing this toxicity are not well described. The purpose of this study was to identify predictors for the development of severe neuropsychiatric toxicity in CML patients receiving rIFNalpha2b-based therapy. PATIENTS AND METHODS: From a prospective cohort of 91 Philadelphia chromosome-positive, previously untreated, chronic-phase CML patients treated on Cancer and Leukemia Group B (CALGB) 9013, a phase II trial of rIFNalpha2b plus cytarabine, the following were recorded at baseline: age, sex, race, pretreatment history of neurologic or psychiatric diagnosis, spleen size, blood counts, and peripheral blast count. Best response to treatment, rIFNalpha2b cumulative dose, dose duration, and dose-intensity were recorded during follow-up. Severe neuropsychiatric toxicity was defined as grade 3 or 4 events, according to CALGB expanded common toxicity criteria. Univariate and multivariate logistic regression analyses were used to identify variables that were associated with the development of severe neuropsychiatric toxicity. RESULTS: Severe neuropsychiatric toxicity developed in 22 patients (24.0%; 95% confidence interval [CI], 15.2% to 32.8%). Toxicity resolved after withdrawal of treatment in all patients. Five of six patients developed recurrence of symptoms with rechallenge. Twelve (63%) of 19 patients with a pretreatment neurologic or psychiatric diagnosis developed severe neuropsychiatric toxicity, as compared with 10 (14%) of 72 patients without a pretreatment neurologic or psychiatric diagnosis (P =.001), resulting in a relative risk of 4. 55 (95% CI, 2.33 to 8.88) for developing severe neuropsychiatric toxicity. No other variables were independently associated with the development of neuropsychiatric toxicity. CONCLUSION: CML patients with a pretreatment history of a neurologic or psychiatric diagnosis are at significantly increased risk of developing severe neuropsychiatric toxicity during therapy with rIFNalpha2b plus cytarabine. Monitoring for neuropsychiatric symptoms and avoiding rechallenge are recommended measures for such patients receiving rIFNalpha2b-based therapy.     

Beneficial effects of post-transfusional hepatitis in acute myelogenous leukemia may be mediated by lipopolysaccharides, tumor necrosis factor alpha and interferon gamma.

Post-transfusional hepatitis is often a complication in patients with acute myelogenous leukemia (AML) in whom survival is paradoxically prolonged. The etiology is unknown. In previous studies, we showed that impaired hepatic endotoxin (lipopolysaccharide, LPS) clearance in patients with acute viral hepatitis A, B, or C versus controls results in endotoxemia and tumor necrosis factor alpha (TNF-alpha) release. TNF-alpha mediates anti-proliferative and differentiating effects in AML cell lines. Interferon-gamma (IFN-gamma) released in acute viral hepatitis, acts in synergy with TNF-alpha. HL60, KG1, and U937 AML cells treated 3, 6, and 9 days with physiologically attainable TNF-alpha (10 U/ml), IFN-gamma (100 U/ml) and LPS (10 ng/ml) levels, have significantly diminished viability and cell growth versus controls. Treatment of HL60 AML cells with LPS/TNF-alpha/IFN-gamma also resulted in significantly increased monocytic pathway differentiation not seen with KG1 or U937 AML cells. HL60 AML cells treated with TNF-alpha/IFN-gamma for 6 days released endogenous TNF-alpha (1.57 U/10(6) cells) upon LPS stimulation compared to less than 0.01 U/10(6) cells in non-LPS-stimulated TNF-alpha/IFN-gamma-treated cells or untreated cells (p less than 0.0001). Untreated HL60 AML cells co-cultured with HL60 cells pretreated for 6 days with TNF-alpha/IFN-gamma and then subjected to LPS stimulation had significantly diminished cell growth compared to controls (p less than 0.0001). This effect could be reversed with anti-TNF-alpha antibody, supporting the concept that endogenous TNF-alpha release by LPS/TNF-alpha/IFN-gamma treated HL60 AML cells may act by paracrine means to suppress growth of other AML cells. The beneficial effects of post-transfusional hepatitis in AML patients may be mediated via LPS/TNF-alpha/IFN-gamma-induced AML cell growth suppression and/or terminal differentiation in which AML cells participate by releasing TNF-alpha after being acted upon by LPS/TNF-alpha/IFN-gamma. Endogenously released TNF-alpha might then act by autocrine/paracrine means to mediate further suppression and terminal differentiation.     

Serum beta-2 microglobulin levels are a significant prognostic factor in Philadelphia chromosome-positive chronic myelogenous leukemia.

Our objective was to investigate the prognostic significance of serum beta-2 microglobulin (B2M) levels among patients with chronic myelogenous leukemia (CML). All patients with Philadelphia chromosome-positive early chronic phase CML (i.e., within 1 year of diagnosis) treated with IFN alpha-based therapy at the M. D. Anderson Cancer Center between 1980 and 1997, in whom pretreatment B2M levels were available, were investigated. Two hundred one patients were evaluable. Their median B2M was 2.2 mg/dl (range, 1.1-20 mg/dl). Serum B2M levels were associated with other variables of prognostic significance, including age, spleen size, WBC count, percentage of peripheral and marrow blasts, and percentage of marrow basophils. Patients with B2M levels >2.9 mg/dl (ie., the upper quartile of the distribution) had a significantly lower rate of major cytogenetic response compared to those in the lower three quartiles (20 versus 52%; P < 0.01). They also had a shorter survival, with a 5-year survival rate of 48%, compared with 75% for those in the lower quartiles (P = 0.01). High B2M levels (>2.9 mg/dl) could identify a group of patients with an adverse outcome within patients in stage I disease (P = 0.02). Results for patients in stages 2-4 were inconclusive because of the small number of patients in these groups. We conclude that serum B2M levels are an important, and probably independent, prognostic factor for patients with CML in early chronic phase treated with IFN-based therapy.     

Adjuvant high-dose interferon alfa-2b in patients with high-risk melanoma

We performed an analysis of toxicity and survival in stage III melanoma patients receiving adjuvant interferon alfa-2b (IFN). This was a retrospective single-arm analysis of 40 patients with stage III melanoma who received (IFN) administered at maximum tolerated doses of 20 mU/m2/day intravenously (i.v.) for 1 month and 10 mU/m2 three times per week subcutaneously (s.c.) for 48 weeks. Toxicity in our series is comparable to that experienced in the Eastern Cooperative Oncology Group (ECOG) 1684 trial, except for higher rates of dose-limiting myelosuppression and hepatotoxicity. All 40 patients experienced constitutional symptoms, but only 14/40 (35%) experienced grade 3 to 4 symptoms. Of the 40 patients, 36 (90%) experienced neurologic symptoms, but only seven (17.5%) experienced grade 3 to 4 neurotoxicity. Two patients stopped treatment because of severe psychiatric symptoms; one patient attempted suicide, and a psychosis developed in another. Thirty-nine (97.5%) patients experienced myelosuppression; 31 (77.5%) developing grade 3 to 4 myelosuppression. Hepatotoxicity was evident in 39 (97.5%) patients, and 26 (65%) experienced grade 3 to 4 hepatotoxicity. Three patients (7.5%) experienced mild renal toxicity. At a median follow-up of 27 months from initiation of therapy, there have been 19 relapses (47.5% disease-free survival [DFS]) and 10 deaths (75% OS) resulting from progression of disease. The DFS compares with the treatment arm in ECOG 1684 at 27 months, but overall survival is higher in our series of patients at the same time point. In a single program setting, IFN can be administered with similar side effects and outcome profiles seen in multi-institutional studies. Modifications in the induction regimen resulted in notably higher hematologic and hepatic toxicities but did not preclude administering further therapy and did not result in increased attrition rate among patients: only nine patients (22.5%) had their treatment stopped as a result of IFN-related toxicity. In comparison, 26% of patients had to have their treatment discontinued because of toxicity in ECOG 1684.     

Mechanisms and management of toxicities associated with high-dose interferon alfa-2b therapy.

PURPOSE: The toxicity associated with adjuvant high-dose interferon-alfa-2b therapy (HDI) for high-risk melanoma can lead to premature discontinuation. It is important to understand the expected adverse events and their underlying mechanisms and to anticipate and aggressively manage toxicity during treatment in order to ensure that patients receive the maximum therapeutic benefit. METHODS: The toxicity profile of HDI was reviewed by examining data from the United States cooperative group trials. Available published data related to the potential mechanisms responsible for the observed adverse events are discussed, and comprehensive recommendations for managing side effects are presented. RESULTS: The HDI regimen is associated with acute constitutional symptoms, chronic fatigue, myelosuppression, elevated liver enzyme levels, and neurologic symptoms. The majority of patients tolerate 1 year of therapy with an understanding of the anticipated toxicities in conjunction with appropriate dose modifications and supportive care. Ongoing monitoring for liver dysfunction and hematologic toxicity is critical to ensure safety. Many of the toxicities associated with interferon-alfa (IFN-alpha) seem to be the result of endogenous cytokines and their effects on the neuroendocrine system. Recent data have also demonstrated that IFN-alpha suppresses the activity of specific CYP450 isoenzymes and that this correlates with discrete toxicities. Pharmacologic interventions are under study for fatigue and depression. An increased understanding of the mechanisms of IFN-alpha-associated toxicity will lead to more rational and effective supportive care and improved quality of life. CONCLUSION: Continued research in this area should lead to improvements in the safety and tolerability of adjuvant therapy for melanoma.     

Dose-dependent treatment benefit in high-risk melanoma patients receiving adjuvant high-dose interferon alfa-2b

This retrospective analysis of 150 consecutive high-risk melanoma patients treated with high-dose interferon alfa-2b at a single institution demonstrates similar relapse-free and overall survival data, as previously published from Eastern Cooperative Oncology Group (ECOG) and Intergroup trials. The data suggest at least a transient dose dependency of the treatment effect on relapse-free and overall survival with high-dose interferon in high-risk melanoma patients. BACKGROUND: Adjuvant high-dose interferon seems to be the best adjuvant treatment option for patients with high-risk melanoma (AJCC-stage IIC, III) after definitive surgery. METHODS: One-hundred fifty consecutive patients were treated at our institution during the period from September 1997 to March 2003 were retrospectively studied. RESULTS: After a median follow-up of 35 months, 63% of patients had developed a melanoma relapse, and 37% were relapse- free. Fifty-five percent of patients are still alive, and 45% had died-all but 3 patients from melanoma. Patients with stage IIC disease demonstrated a similar unfavorable course of disease as patients with stage IIIC disease (2-year relapse-free survival 18% and 26%). We identified two groups of patients with different cumulative interferon dose-levels (> or =90% and <90% of the projected dose, according to the protocol), who demonstrated at least transient differences, both in terms of relapse-free and overall survival; the predictive impact was statistically independent upon the Cox regression analysis. CONCLUSIONS: Our clinical data are consistent with the published ECOG and Intergroup data dealing with highdose interferon in high-risk melanoma patients. The data suggest a dose-dependency on the treatment effect and, therefore, support further prospective trials comparing different dose-distribution patterns in high-dose interferon.     

Randomized study of the duration of treatment with interferon alfa-2B in patients with hairy cell leukemia

Several previous studies have demonstrated that both partially purified and recombinant alpha-interferons (alpha-IFNs) have high response rates in advanced hairy cell leukemia. However, the optimal dose and duration of therapy have not yet been defined. In this study, 90 patients were randomized after 12 months of IFN alfa-2b therapy with a standard dose of 2 X 10(6) U/m2 sc three times weekly to either no further therapy or an additional 6 months of therapy (18 mo total). There was no significant difference in the peripheral blood cell counts between the two groups (when analyzed) dating from the end of IFN therapy rather than from the time of randomization. Eighteen evaluable patients relapsed and were re-treated with IFN: 11 in the no-further-therapy group and 7 in the treated group. No patient was resistant to re-treatment with IFN. There was a significantly greater incidence of fatigue in the treated group (44% vs. 21%; P = .02) during the first 6 postrandomization months. We conclude that the duration of IFN therapy does not influence the clinical course after therapy is discontinued, but responses are maintained while patients receive therapy. However, because of a high incidence of fatigue with prolonged therapy and the ability to reinduce a second response, we recommend that IFN therapy be discontinued after 12 months in asymptomatic patients.     

Cost-Effectiveness of interferon alfa-2b added to chemotherapy for high-tumor-burden follicular non-Hodgkin's lymphoma.

Recent data from GELF (Groupe d'Etude des Lymphomes Folliculaires) have shown that the addition of interferon alfa-2b (IFN) to a doxorubicin-containing regimen (CHVP: cyclophosphamide, doxorubicin, teniposide and prednisone) prolongs both progression-free survival and overall survival in high-tumor-burden follicular non-Hodgkin's lymphoma. This gain must be weighed against the incremental toxicity and cost of IFN over CHVP alone and the objective here was, to determine the marginal cost-effectiveness of additive IFN in the specific setting of high-tumor-burden follicular non-Hodgkin's lymphoma. Meta-analysis of GELF trial results employing a Markov model was used with three health states: No Progression, Progressive Disease, and Death. Treatment response, survival and toxicity data are drawn from the GELF study. The current study is based on the final analysis of 242 patients (J Clin Oncol 1998;16:2332-2338), with a six year median follow-up for overall survival (median overall survival: not reached for CHVP + IFN vs 5.6 years for CHVP Only, p = 0.008). Measurements: Quality of life data (utilities) are taken from studies with similar dosing of IFN, from Q-TwiST (quality adjusted time without symptoms or toxicity) analysis of the GELF data and from a panel of experts gathered to develop treatment models for high-tumor-burden follicular non-Hodgkin's lymphoma. Costs and quality-adjusted years of life saved were discounted at 3% per annum. Setting: Costs determined for university medical centers in the United States. Results showed that, at the median cohort age of 52, IFN add 9.9 quality-adjusted months at an added cost of $13,900 (marginal cost-effectiveness of $16,900 per quality-adjusted life year, or QALY). A more complex, two-stage model approximates the actual cohort survival curves much better than a simple, one-stage model, but both models yield essentially the same marginal cost-effectiveness. Sensitivity analysis to quality of life on IFN shows marginal cost-effectiveness ranging from $15,200/QALY (no penalty for IFN) to $21,300/QALY (20% quality adjustment, greater than that reported). The model is quite insensitive to the probability of IFN toxicity. The model is moderately sensitive to the efficacy of IFN in delaying progression, particularly in the first 18 months (pProgI), but the marginal cost-effectiveness does not rise to $50,000/QALY until pProgI increases 220% from the baseline. Although the model is moderately sensitive to the cost of IFN (cIFN), marginal cost-effectiveness is below $50,000/QALY for values of cIFN below $2580/month (baseline cIFN = $850/month, corresponding to a marginal cost-effectiveness of $16,900/QALY in the baseline case). If the model is modified to reflect the 14% overall survival advantage at five years found in trials utilizing more intensive initial chemotherapy (including the GELF trial), then the marginal cost-effectiveness drops to $11,900/QALY in the baseline case. In condusion, based on data from the GELF study, low-dose interferon alfa-2b is cost-effective when added to CHVP therapy in the treatment of high-tumor-burden follicular non-Hodgkin's lymphoma. The analysis is robust: the model employs very conservative assumptions, and additive IFN remains cost-effective over wide ranges of variables in sensitivity analyses. The marginal cost-effectiveness is best expressed as being in the range of $12,000/QALY to $17,000/QALY in the baseline case. A simple Markov model can be used to describe treatment regimens with distinct periods of therapy.     

Improved results with the addition of interferon alfa-2b to dacarbazine in the treatment of patients with metastatic malignant melanoma

Sixty-four patients with histologically confirmed metastatic malignant melanoma were entered on a prospectively controlled randomized trial. Patients received dacarbazine (DTIC) alone or DTIC plus interferon (IFN) alfa-2b. Patients were reasonably balanced with respect to age, sex, performance status (PS), site of metastases, and number of metastatic sites. Objective response (complete plus partial remission [CR + PR]) was documented in six patients on DTIC and in 16 patients on DTIC plus IFN alfa-2b. Median time to treatment failure (TTF) and median survival are significantly better on the combination arm, with some long-term CRs observed. More toxicity was encountered in the combination arm, which was acceptable except in three patients where treatment was discontinued because of IFN toxicity.     

Destruction of circulating leukemia cells by phagocytosis in rats with myelogenous leukemia.

Acute myelogenous leukemia was induced in outbred Long-Evans rats by iv injections of leukemia cells from a subcutaneous tumor of Shay myelogenous leukemia. In rats with this leukemia the peripheral white blood cell (WBC) counts varied from 2.4 to 700 X 10(9)/liter. No differences were found in the bone marrow of the rats with the high WBC counts and that of rats with low WBC counts. This observation could explain the large variations in the number of circulating leukemia cells caused by differences in cell proliferation or delivery of cells into the circulation. Massive phagocytosis of leukemia cells occurred in animals with low WBC counts (less than 12 X 10(9)/liter) but not in animals with high WBC counts (greater than 150 X 10(9)/liter). This phagocytosis was directed against circulating leukemia cells. The main phagocytes were Kupffer's cells of the liver and macrophages of the spleen parenchyma. In addition, phagocytosis occurred in the spleens and bone marrow by intravascular macrophages, which were derived from extravascular sites. The endothelium of the postcapillary venules of the lymph nodes participated in the phagocytosis of circulating leukemia cells while continuing to be the locus of lymphocytic return from circulation to lymphatic parenchyma. The factors underlying the differences in macrophage activity between the rats with high and low WBC counts were unknown.     

Treatment of the chronic phase of chronic myeloid leukemia with an intermittent schedule of recombinant interferon alfa-2b and cytarabine: results from CALGB study 9013

Despite nine studies reporting the results achieved when treating patients with chronic myeloid leukemia (CML) with interferon (rIFNalpha) and cytarabine (araC), the optimal doses and schedule for this combination remain to be determined. Results of imatinib mesylate (STI-571) in chronic phase CML are preliminary, thus, trials of rIFNalpha-2b/araC in CML are of continued interest. We report the results of CALGB study 9013, providing a 10-year follow-up on 88 evaluable previously untreated patients. Cycles of therapy with rIFNalpha-2b and araC sufficient to cause a decline in either the white blood cell (WBC) count to < 2000/microl or platelets to < 50,000/microl were given. The starting dose of rIFNalpha-2b was 5 million units (mu)/m2/day subcutaneously (s.c.) and of araC 10 mg/m2 twice daily s.c. Treatment was discontinued when cytopenia occurred and was restarted when both the WBC and platelet counts had recovered. Bone marrow was obtained regularly for morphologic, cytogenetic and molecular studies. Medians at entry included age 48 years, WBC = 89,900/microl and platelets = 345,000/microl. The performance status was 0 or 1 in 88%; splenomegaly was present in 46%. Fifty five (63%) patients had a complete hematologic response and 10 (11%) had a partial hematologic response for an overall response rate of 74%. Median time to best response was 5.3 months. Median survival for all patients from study entry was 81 months, the 5-year survival probability was 65%. When 28 patients were censored at the time of bone marrow transplantation the median survival was 82 months. Grade 3 anorexia, nausea, vomiting and diarrhea developed in 15, 27, 13 and 7%, respectively. Mild to moderate elevations of transaminases occurred in 42%, and were severe in 5%. Sixty-three patients had adequate follow-up cytogenetic studies: 10 had a complete cytogenetic response (CCyR), 23 partial (PCyR, 50-99% normal cells), 20 minor and 10 no response (CALGB criteria). Thus, the CCyR plus PCyR rate among these 63 patients was 52%. Assuming the 25 patients with no cytogenetic follow-up as non-responders, 38% of the 88 patients had at least a PCyR. The median time to CCyR or PCyR was 5.6 months. The median time to best response in these 33 patients was 10.0 months, and median duration of cytogenetic response was 28 months. Cytogenetic responders had significantly longer survival than non-responders (p = 0.01) using a landmark analysis at 18 months. This intermittent schedule of rIFNalpha-2b/ara-C has a high response rate in patients with CML with acceptable toxicity.