Targeting p53 in Vivo: A First-in-Human Study With p53-Targeting Compound APR-246 in Refractory Hematologic Malignancies and Prostate Cancer

Purpose

APR-246 (PRIMA-1MET) is a novel drug that restores transcriptional activity of unfolded wild-type or mutant p53. The main aims of this first-in-human trial were to determine maximum-tolerated dose (MTD), safety, dose-limiting toxicities (DLTs), and pharmacokinetics (PK) of APR-246.

Patients and Methods

APR-246 was administered as a 2-hour intravenous infusion once per day for 4 consecutive days in 22 patients with hematologic malignancies and prostate cancer. Acute myeloid leukemia (AML; n = 7) and prostate cancer (n = 7) were the most frequent diagnoses. Starting dose was 2 mg/kg with dose escalations up to 90 mg/kg.

Results

MTD was defined as 60 mg/kg. The drug was well tolerated, and the most common adverse effects were fatigue, dizziness, headache, and confusion. DLTs were increased ALT/AST (n = 1), dizziness, confusion, and sensory disturbances (n = 2). PK showed little interindividual variation and were neither dose nor time dependent; terminal half-life was 4 to 5 hours. Tumor cells showed cell cycle arrest, increased apoptosis, and upregulation of p53 target genes in several patients. Global gene expression analysis revealed changes in genes regulating proliferation and cell death. One patient with AML who had a p53 core domain mutation showed a reduction of blast percentage from 46% to 26% in the bone marrow, and one patient with non-Hodgkin's lymphoma with a p53 splice site mutation showed a minor response.

Conclusion

We conclude that APR-246 is safe at predicted therapeutic plasma levels, shows a favorable pharmacokinetic profile, and can induce p53-dependent biologic effects in tumor cells in vivo.

Continuing high early death rate in acute promyelocytic leukemia: a population-based report from the Swedish Adult Acute Leukemia Registry

Our knowledge about acute promyelocytic leukemia (APL) patients is mainly based on data from clinical trials, whereas population-based information is scarce. We studied APL patients diagnosed between 1997 and 2006 in the population-based Swedish Adult Acute Leukemia Registry. Of a total of 3897 acute leukemia cases, 3205 (82%) had non-APL acute myeloid leukemia (AML) and 105 (2.7%) had APL. The incidence of APL was 0.145 per 100,000 inhabitants per year. The median age at the time of diagnosis was 54 years; 62% were female and 38% male. Among younger APL patients, female sex predominated (89% of patients <40 years). Of the 105 APL patients, 30 (29%) died within 30 days (that is, early death (ED)) (median 4 days) and 28 (26%) within 14 days from diagnosis. In all, 41% of the EDs were due to hemorrhage; 35% of ED patients never received all-trans-retinoic acid treatment. ED rates increased with age but more clearly with poor performance status. ED was also associated with high white blood cells, lactate dehydrogenase, creatinine, C-reactive protein and low platelet count. Of non-ED patients, 97% achieved complete remission of which 16% subsequently relapsed. In total, 62% are still alive at 6.4 years median follow-up. We conclude that ED rates remain very high in an unselected APL population.

BCRP mRNA expression v. clinical outcome in 40 adult AML patients

Efflux pumps are considered being mechanisms behind drug resistance in acute myeloid leukaemia (AML). A recently described efflux pump, breast cancer resistance protein (BCRP), can be expressed in AML, but its clinical importance is uncertain. In this study BCRP mRNA expression was determined in samples from 40 AML patients by real-time RT-PCR. The expression varied from negative to 76 times that of control cells. There was no difference in BCRP mRNA expression between patients responding to induction treatment and non-responders. However, in the group of responders, the 14 patients with the highest expression had significantly shorter overall survival (mean 38 months, SEM 15 months) than the 14 patients with the lowest (74 months, SEM 16 months) (P = 0.047). This suggests a possible role of BCRP in drug resistance in AML.

P-Glycoprotein inhibitor valspodar (PSC 833) increases the intracellular concentrations of daunorubicin in vivo in patients with P-glycoprotein-positive acute myeloid leukemia

PURPOSE

The aim of the present study was to evaluate the effect of the cyclosporine derivative valspodar (PSC 833; Amdray, Novartis Pharma, Basel, Switzerland) on the concentration of daunorubicin (dnr) in leukemic blast cells in vivo during treatment.

PATIENTS AND METHODS

Ten patients with acute myeloid leukemia (AML) were included. Leukemic cells from seven of the patients were P-glycoprotein (Pgp)-positive. dnr 100 mg/m(2) was given as a continuous infusion over 72 hours. After 24 hours, a loading dose of valspodar was given, followed by a 36-hour infusion of 10 mg/kg per 24 hours. Blood samples were drawn at regular intervals, and concentrations of dnr and its main metabolite, daunorubicinol, in plasma and isolated leukemic cells were determined by high-pressure liquid chromatography.

RESULTS

The mean dnr concentrations in leukemic cells 24 hours after the start of infusion (before valspodar) were 18.8 micromol/L in Pgp-negative samples and 13.5 micromol/L in Pgp-positive samples. After 8 hours of valspodar infusion, these values were 25.8 and 24.0 micromol/L, respectively. The effect of valspodar was evaluated from the ratio of the area under the curve (AUC) for dnr concentration versus time in leukemic cells to the AUC for dnr concentration against time in the plasma. For the seven patients with Pgp-positive leukemia, the mean ratio increased by 52%, from 545 on day 1 to 830 on day 2 (P<.05) when valspodar was given. In the three patients with Pgp-negative leukemia, no significant difference was observed.

CONCLUSION

These results strongly suggest that valspodar, by interacting with Pgp, can increase the cellular uptake of dnr in leukemic blasts in vivo.

Use of inflammatory markers for early detection of bacteraemia in patients with febrile neutropenia

The aim of the study was to evaluate the ability of procalcitonin, C-reactive protein, serum amyloid A, interleukin-6 and interleukin-8 to predict bacteraemia during the 2 first d of fever in neutropenic patients. A total of 94 febrile neutropenic episodes in 60 patients were studied. Plasma samples were analysed at 10-h intervals from the onset of fever. Clinical events were categorized into 4 groups: 1) bacteraemia caused by other agents than coagulase-negative staphylococci (non-CNS bacteraemia) (n = 21), 2) coagulase-negative staphylococci bacteraemia (n = 15), 3) microbiologically or clinically documented infection without bacteraemia (n = 26) and 4) fever of unknown origin (n = 32). In non-CNS bacteraemia all markers, except for serum amyloid A, showed significantly higher levels compared to patients with fever of unknown origin (p < 0.05). For non-CNS bacteraemia the highest negative predictive value was found for procalcitonin (94%), followed by interleukin-6 (89%), C-reactive protein (88%) and interleukin-8 (87%). Procalcitonin, with a cut-off level of 1.4 ng/ml during 10-20 h after fever onset, showed the highest positive predictive value (67%) for a non-CNS bacteraemia. In conclusion, the value of the analysed markers to predict a non-CNS bacteraemia in neutropenic patients was limited due to low sensitivity and positive predictive value. However, procalcitonin, interleukin-6, C-reactive protein, and interleukin-8 could give useful information for the clinician in excluding a non-CNS bacteraemia.

Assessment of systemic inflammation markers to differentiate a stable from a deteriorating clinical course in patients with febrile neutropenia

In this study, we evaluated the predictive values of procalcitonin (PCT), C-reactive protein (CRP), interleukin-6 (IL-6) and serum amyloid A (SAA) for determining the clinical course in febrile neutropenic patients. Daily plasma analyses during the fever course were performed in 101 episodes with fever and chemotherapy-induced neutropenia (neutrophil count <0.5 x 10(9)/L). Procalcitonin (PCT) and IL-6 values were significantly higher in febrile episodes in patients who developed complications. Procalcitonin with a cut-off value of < or =0.4 ng/mL or IL-6 < or =50 pg/mL 3 d after fever onset indicated daily high negative predictive values (NPVs) (91-100%) for episodes with complications. No marker could predict deterioration; however, daily low plasma concentrations of PCT or IL-6 during the first 8 d of fever were found to be a good predictor of no subsequent complications in neutropenic patients and therefore to be a helpful tool for limiting anti-microbial therapy.

Large-volume apheresis for the harvest of peripheral blood progenitor cells for autologous transplantation

BACKGROUND

The mobilization and harvest of a sufficient number of peripheral blood stem and progenitor cells for autologous transplantation is an important aspect of treatment in patients with certain hematologic and solid tumor disease. The level of CD34+ cells in peripheral blood is often used as a predictor of successful harvest.

STUDY DESIGN AND METHODS

A total of 129 apheresis procedures in 38 patients have been investigated retrospectively to evaluate the possibility to predict the outcome by other measures, such as total treated blood volume (TBV) during the apheresis.

RESULTS

No significant correlation was observed between the level of CD34+ cells per kg of body weight in collected apheresis components and the TBV in all 129 apheresis procedures. However, analysis of results from 22 apheresis procedures with TBV > 16 L (large-volume apheresis) and with < 10 x 10(3) CD34+ cells per mL in the peripheral blood found a correlation between TBV and the number of CD34+ cells per kg of body weight in the collected component (R2 = 0.585, p = 0.005). In patients who underwent large-volume apheresis (> 16 L) and who had < 10 x 10(3) CD34+ cells per mL in their peripheral blood, the number of CD34+ cells in the apheresis component was not correlated with that in the peripheral blood prior to harvest (R2 = 0.262, p = 0.1569). In the patients who underwent apheresis procedures with TBV < 16 L and who had > 20 x 10(3) CD34+ cells per mL in their peripheral blood, there was a correlation between the number of CD34+ cells in the component and the number of CD34+ cells in the peripheral blood (R2 = 0.800, p = 0.0000). However, there was not a correlation in this group between the number of CD34+ cells in the component and the TBV. There were no significant differences in the content of CD34+/CD33+ and CD34+/ HLA-DR+ cells in the collected component in the two groups.

CONCLUSION

TBV appears to be critical for the collection of a sufficient number of progenitor cells in patients with < 10 x 10(3) CD34+ cells per mL in peripheral blood.

High-dose cytarabine in upfront therapy for adult patients with acute lymphoblastic leukaemia

In this national study, we have evaluated a new intensive chemotherapy protocol for adult patients with untreated acute lymphoblastic leukaemia (ALL). One hundred and fifty-three patients with median age 42 years received induction therapy with high-dose cytarabine (Ara-C), cyclophosphamide, daunorubicin, vincristine and betamethasone. A high complete remission (CR) rate (90%) was achieved in patients < 60 years compared with 70% in patients > 60 years (P = 0.004). The estimated 3 year overall survival for all patients was 29% (CI 21-36%) and the estimated continuous complete remission (CCR) at 3 years for the patients achieving CR according to the protocol was 36% (CI 27-45%). A favourable pretreatment characteristic was pre-B phenotype, especially for patients < 40 years without any high-risk factor, with an estimated CCR at 3 years of 62% (CI 41-82%). Stem cell transplantation (SCT) as post-remission therapy, mainly for high-risk patients, gave an estimated 3 year disease free survival (DFS) after SCT of 39% (CI 24-54%). No significant differences in DFS could be found between autologous, related or unrelated donor transplantation. We conclude that this intensive protocol resulted in a high CR rate combined with acceptable side-effects and a favourable CCR for patients with pre-B ALL.

Increased remissions from one course for intermediate-dose cytosine arabinoside and idarubicin in elderly acute myeloid leukaemia when combined with cladribine. A randomized population-based phase II study

Cladribine has single-drug activity in acute myeloid leukaemia (AML), and may enhance the formation of the active metabolite (ara-CTP) of cytosine arabinoside (ara-C). To evaluate the feasibility of adding intermittent cladribine to intermediate-dose ara-C (1 g/m2/2 h) b.i.d. for 4 d with idarubicin (CCI), we performed a 2:1 randomized phase II trial in AML patients aged over 60 years. Primary endpoints were time to recovery from cytopenia and need for supportive care following the first course. Sixty-three patients (median 71 years, range 60-84 years) were included, constituting 72% of all eligible patients. Toxicity was limited, with no differences between the treatment arms. The early toxic death rate was 11%. The median time to recovery from neutropenia and thrombocytopenia was 22 and 17 d from the start of course no. 1, respectively, and the requirement for platelet and red cell transfusions was four and eight units respectively. Patients had a median of 8 d with fever over 38 degrees C, and 17 d with intravenous antibiotic treatment. The overall complete remission (CR) rate was 62%, with 51% CR from one course of CCI in comparison with 35% for the two-drug therapy (P = 0.014). The median survival with a 2-year follow-up was 14 months, and the 2-year survival was over 30%, with no differences between the treatment arms. Considering the median age and our population-based approach, the overall results are encouraging.

Pharmacokinetics of daunorubicin and doxorubicin in plasma and leukemic cells from patients with acute nonlymphoblastic leukemia

The pharmacokinetics of daunorubicin and doxorubicin were studied in plasma and leukemic cells from 16 patients with acute nonlymphoblastic leukemia during 19 courses of treatment with the unconjugated or DNA-conjugated drugs. Daunorubicin and doxorubicin are high-clearance drugs with very high apparent volumes of distribution, indicating a pronounced tissue affinity. This was more pronounced in the case of doxorubicin and may explain the reduced cardiotoxicity of the DNA-complexes. Daunorubicin reached higher intracellular peak concentrations than doxorubicin, but the latter drug was retained much longer. The cell/plasma concentration ratio was higher for daunorubicin than for its reduced metabolite daunorubicinol. No doxorubicinol was found intracellularly. The observed differences in cellular pharmacokinetics between daunorubicin and doxorubicin may explain the difference between the clinical activity spectras of these two drugs. DNA-conjugation did not markedly modify the uptake of daunorubicin in the leukemic cells, whereas the mean intracellular accumulation of doxorubicin was 60% higher when the drug was administered as a DNA-conjugate. This may enhance the selectivity of doxorubicin in the treatment of acute leukemia.

In vitro drug testing in patients with acute leukemia with incubations mimicking in vivo intracellular drug concentrations

The differential staining cytotoxicity (DiSC) assay was evaluated as a predictive test for response to therapy in patients with acute non-lymphoblastic leukemia. Incubations were designed in such a way that the intracellular concentrations of cytostatic drugs in vitro paralleled those in vivo. Leukemic cells were isolated from 53 patients with acute non-lymphocytic leukemia. 13 of these patients died early due to supportive care failure and were not evaluable for the predictive drug testing. Of the remaining 40 patients, 25 entered a complete remission (CR) and 15 had a resistant disease (RD). According to the patients randomization to therapy the cells were incubated with anthracyclines and Ara-C separately and in combination. After 4 days of culturing in liquid medium the in vitro cytotoxicity was determined by dye exclusion according to Weisenthal. The cytotoxic effect in vitro was significantly higher on cells from patients who achieved a CR compared to patients with RD after incubations with anthracyclines 0.2 mumol/l (p less than or equal to 0.005), Ara-C 0.5 mumol/l (p less than or equal to 0.05) and with the combination of anthracyclines with Ara-C (p less than or equal to 0.0005). The best predictive value was achieved when incubations with 0.2 mumol/l anthracyclines and 0.5 mumol/l Ara-C were analyzed together. With these incubations cells from 20 out of 21 patients who achieved CR showed either less than or equal to 60% surviving cells after the anthracycline incubation or less than or equal to 35% surviving cells after the Ara-C incubation. Cells from 11 out of 13 patients with RD did not fulfill either of these criteria. In vitro drug sensitivity was significantly correlated to a prolonged survival (p less than 0.01). We conclude that, when performed with incubations that mimic in vivo tumor cell exposure to cytostatic drugs, the DiSC assay shows a high correlation to clinical outcome for patients with acute non-lymphocytic leukemia.

No benefit from adding GM-CSF to induction chemotherapy in transforming myelodysplastic syndromes: better outcome in patients with less proliferative disease

In this prospective randomized multicenter trial 93 patients, median age 72 years, with RAEB-t (n=25) and myelodysplastic syndrome (MDS)-AML (n=68) were allocated to a standard induction chemotherapy regimen (TAD 2+7) with or without addition of granulocyte-macrophage-CSF (GM-CSF). The overall complete remission (CR) rate was 43% with no difference between the arms. Median survival times for all patients, CR patients, and non-CR patients were 280, 550, and 100 days, respectively, with no difference between the arms. Response rates were significantly better in patients with serum lactate dehydrogenase (S-LDH) levels </=9.5 microkat/l, bone marrow cellularity </=70%, and WBC counts <4.0 x 10(9)/l, but S-LDH was the only variable independently associated with response by logistic regression analysis. Cox's regression analysis identified four significant prognostic factors for survival: bone marrow cellularity, S-LDH, cytogenetic risk group (International Prognostic Scoring System), and age. Only bone marrow cellularity (P=0.01) and S-LDH (P=0.0003) retained statistical significance in the log-rank test. Severe adverse events were significantly more common in the GM-TAD arm (P=0.01). Thus, addition of GM-CSF to chemotherapy showed no clinical benefit in terms of response but carried an increased risk for side effects. We present a clinically useful tool to predict response to chemotherapy and survival in elderly patients with transforming MDS, favoring patients with features of less proliferative disease.

The cytotoxic effects of 5-OH-1,4-naphthoquinone and 5,8-diOH-1,4-naphthoquinone on doxorubicin-resistant human leukemia cells (HL-60)

The effect of 5-OH-1,4-naphthoquinone and 5,8-diOH-1,4-naphthoquinone, two quinones highly reactive with oxygen, was studied on HL-60 and HL-60R cells. The multidrug resistance developed by the doxorubicin-resistant HL-60 cell line did not prevent the cytotoxic effect of these compounds, at clinically relevant concentrations. An increase in cellular defenses against oxygen radicals seemed to be one of the features developed by HL-60R, since the homogenate from this cell line had only 65% of the ability of the original cell line to form oxygen radicals during doxorubicin reduction. This result may be explained in part by the slight increase in superoxide dismutase and DT-diaphorase enzymatic activities.

In the shadow of bad news - views of patients with acute leukaemia, myeloma or lung cancer about information, from diagnosis to cure or death

Background

Many studies have been published about giving and receiving bad messages. However, only a few of them have followed the patients all the way through a disease as is done in this study. Many studies have been written about patients' coping strategies. In this study we will keep within the bounds of coping through information only. The aim of the study is to investigate patients' views of information during the trajectory of their disease, whether their reactions differ from each other and whether they differ in different phases of the disease.

Methods

Twelve patients with malignant haematological diseases or lung cancer were followed with interviews from diagnosis to recovery or into the terminal phase or at most for two years. The method is qualitative, using semi-structured interviews.

Setting: Örebro University Hospital or the patient's home.

Results

All patients described themselves as well informed from the start but in later phases of their disease some of them came to express a great uncertainty about the progressing disease and about the approaching death. Most of them, regardless of whether they had a haematological malignancy or lung cancer, expressed a wish to be well informed all through the disease and even when the messages were bad. Different strategies for coping with information, however, affected how they then dealt with the information received. Four such coping strategies were found: 1) Information-dependent and accepting; 2) Information-dependent but denying; 3) Medically informed and accepting; 4) Medically informed but denying.

Conclusion

To several patients there was an unmet need for information about the progressing disease and the approaching death. To optimize the care of these patients it seems important that the physician is aware of patients' need for information even when the news is bad. Knowing the patient's information strategy could probably function as a key for the physician to communicate with patients on these matters.

A phase I/II study of the MDR modulator Valspodar (PSC 833) combined with daunorubicin and cytarabine in patients with relapsed and primary refractory acute myeloid leukemia

The cyclosporine analog Valspodar (PSC 833, Novartis Pharma) is a strong inhibitor of the mdr1 gene product p-glycoprotein (pgp). A phase I/II study was conducted in order to evaluate if addition of Valspodar to treatment with daunorubicin and cytarabine, given to patients with primary refractory or relapsed acute myeloid leukemia, could increase the complete remission rate.Fifty-three patients were treated in cohorts of three to six patients. Twelve patients reached a complete remission in bone marrow, five of whom also normalized their peripheral blood values. Three patients experienced treatment-related deaths from pneumonia, liver failure and cerebral hemorrhage, respectively. It is concluded that Valspodar 10 mg/kg per 24 h in combination with daunorubicin 45 mg/m(2) for 3 days and cytarabine 1 g/m(2) twice daily for 4 days is tolerable in this heavily pre-treated group of patients. Due to the moderate treatment results, the phase II part of the study was ended prematurely. The modulation of only pgp did not give an obvious improvement of the treatment results in this group of patients.

Kinetics of peripheral blood stem cell harvests during a single apheresis

BACKGROUND

The enumeration of CD34+ cells in the peripheral blood of patients before leukapheresis is commonly used to predict the outcome of stem cell harvests. The concept that an increased number of transplanted cells gives faster marrow reconstitution triggers an interest in investigating the kinetics of peripheral blood stem cells during leukapheresis. The aim of this study was to investigate the issue of recruitment of hematopoietic progenitor cells during a single leukapheresis.

STUDY DESIGN AND METHODS

Nine leukapheresis procedures (in 8 patients) were investigated. In each case, 3 blood volumes were processed. Samples from peripheral blood, the collection line of apheresis equipment, and the collected component were obtained after each blood volume was processed. The enumeration of CD34+ cells was performed, and the total number of progenitors, as a sum of the number of cells in the peripheral blood and the number of cells in the collected component, was calculated.

RESULTS

A mean of 13.3 L of blood was processed, and a component with a mean volume of 424 mL and a mean of 10.1 x 10(6) CD34+ cells per kg of body weight was collected. White cell and mononuclear cell counts in peripheral blood declined concomitantly during the procedures. The calculated total number of cells--that is, the sum of the number of cells in the collected component and the number of cells in the peripheral blood--showed a concomitant, but not equal, rise in polymorphonuclear cells, mononuclear cells, and CD34+ cells during the leukapheresis. This apparent mobilization of progenitors into the peripheral blood did not correlate with the slightly increased number of polymorphonuclear cells or with the more pronounced increase in mononuclear cells.

CONCLUSION

There is a substantial recruitment of progenitor cells during a single leukapheresis.

Comparison of a bioluminescence assay with differential staining cytotoxicity for cytostatic drug testing in vitro in human leukemic cells

An ATP assay using bioluminescence was evaluated for its ability in determining the cytotoxic effect of antileukemic drugs. Leukemic cells from 32 patients with ANLL were used to compare the ATP assay with the differential staining cytotoxicity assay (DiSC). Cells were incubated with doxorubicin, daunorubicin, idarubicin, mitoxantrone and ara-C in conditions that were adapted to mimic the in vivo exposure of leukemic cells to cytostatic drugs. After incubation the cells were cultured in liquid medium for 4 days and then analyzed for ATP content using the firefly luciferase method in an automated procedure. The cytotoxic effect as measured by both methods correlated satisfactorily (r = 0.8). We conclude that the automated ATP assay can replace the more time consuming DiSC assay for in vitro drug testing in ANLL.

Topoisomerase II-alpha expression in different cell cycle phases in fresh human breast carcinomas

Topoisomerase II-alpha (topo II alpha) is the key target enzyme for the topoisomerase inhibitor class of anti-cancer drugs. In normal cells, topo II alpha is expressed predominantly in the S/G2/M phase of the cell cycle. In malignant cells, in vitro studies have indicated that the expression of topo II alpha is both higher and less dependent on proliferation state in the cell. We studied fresh specimens from 50 cases of primary breast cancer. The expression of topo II alpha in different cell cycle phases was analyzed with two-parameter flow cytometry using the monoclonal antibody SWT3D1 and propidium iodide staining. The expression of topo II alpha was significantly higher in the S/G2/M phase of the cell cycle than in the G0/G1 phase in both DNA diploid and DNA non-diploid tumors. In 18 of 21 diploid tumors, and in 25 of 29 non-diploid tumors, >50% of the topo II alpha-positive cells were in the G0/G1 phase. This significant expression of topo II alpha in the G0/G1 phase of the cell cycle may have clinically important implications for treatment efficacy of topoisomerase II inhibitors.

Adjustment of incidence rates after an estimate of completeness and accuracy in registration of acute leukemias in a Swedish population

Earlier studies have revealed undernotification of hematological malignancies in Swedish and other Cancer Registries. We present epidemiological data on AML, ALL and unspecified AL in adults diagnosed 1987-1992 in a well-defined population. Blast crises of CML were excluded. The Swedish Cancer Registry and Cause of Death Registry were compared and patient records reviewed for validation. When available, listings of pathology bone marrow reports and inpatient discharge diagnoses were utilized for casefinding. 260 cases of acute leukemias could be verified in a population of 663,135 adults, corresponding to a yearly incidence of 6.5/100,000. The median age of the patients was 69.2 years. 214 cases were AML, 38 ALL and eight unspecified AL. Undernotification in the Cancer Registry was found to be 15.4%, greater for AML and unspecified AL than for ALL. In addition the coding was not uniform, resulting in an incidence rate in adults of 5.3/100,000 for the Cancer Registry which is 18.5% lower than that of our study. A significant survival advantage was seen for notified patients. Combination of the Cancer Registry and Cause of Death Registry gave acceptable coverage, omitting only four patients. As the incidence of acute leukemias in our study is comparatively high, we hypothesize that underestimation of incidence and overestimation of survival are general problems for cancer registries.

Treatment, long-term outcome and prognostic variables in 214 unselected AML patients in Sweden

With the aim of describing an unselected series of acute myeloid leukaemias (AML) in adults, patients diagnosed 1987-1992 in the Orebro region of central Sweden were reviewed by investigating hospital records. By utilizing: (1) The Swedish Cancer Registry, (2) The Cause of Death Registry, (3) listings of pathology bone marrow reports and (4) listings of inpatient discharge diagnoses, we attempted to find all patients. Among secondary AML, only blast-crises of CML were excluded. A total of 214 cases of AML with a median age of 69.5 years were verified corresponding to a mean yearly incidence in adults of 5.4/100 000. Of all patients, 56% had received 'high-dose' induction treatment, 28% 'low-dose' treatment and 16% no cytostatic treatment. Median survival for all patients was 5.8 months and the probability of survival at 5 years was 9.3%. The 120 'high-dose' treated patients had a total CR rate of 67%, median CR duration 10.1 months and median survival 11.4 months. Age, LDH and kidney function were found to be independent prognostic variables for survival. The inclusion of patients unreferred from district hospitals makes this study unique as an example of unselected AML.

Granulocyte-macrophage colony-stimulating factor to increase efficacy of mitoxantrone, etoposide and cytarabine in previously untreated elderly patients with acute myeloid leukaemia: a Swedish multicentre randomized trial

A total of 110 patients, aged 64 years or over, with de novo acute myeloid leukaemia (AML) and white blood cell counts <50 x 109/l were treated with 3 d of cytarabine 1 g/m2 twice daily, mitoxantrone 12 mg/m2 and etoposide 200 mg/m2, randomized with or without the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) 200 microg/m2. The primary aim was to evaluate the effect of GM-CSF on the remission rate. Secondary aims included comparison of duration of remission, survival and infectious complications and the impact of maintenance therapy with thioguanine. Complete remission (CR) was achieved by 64% of patients without GM-CSF, and by 65% of patients who received GM-CSF, the median remission duration was 13 vs. 6 months, the median overall survival (OS) was 14 vs. 9 months, the mean time to neutrophil recovery was 25 vs. 17 d (P = 0.03) and the number of positive blood cultures was 46 vs. 39 (P = 0.05) respectively. The impact of thioguanine remains unanswered since only 30 patients remained in CR after consolidation therapy. We conclude that induction therapy is feasible with acceptable toxicity in elderly patients with AML, albeit with a high relapse rate and short OS. GM-CSF prior to, and in combination with, induction treatment reduced the time to neutrophil recovery and the number of neutropenic septicaemia cases but did not improve the OS of AML in the elderly.

In vitro chemosensitivity testing in acute non lymphocytic leukemia using the bioluminescence ATP assay

The ATP assay is a short term in vitro chemosensitivity assay where the amount of viable cells are determined by their content of ATP. The aim of the study was to compare the in vitro results of six cytostatic drugs to the clinical outcome in 83 acute non-lymphocytic leukemia (ANLL) patients. The secondary ANLL at diagnosis showed an in vitro resistance to daunorubicin that was significantly higher compared to de novo ANLL at diagnosis (P<0.003). De novo ANLL at diagnosis that achieved complete remission (CR) were significantly more sensitive to daunorubicin compared to those who didn't achieve CR (P<0.05). There was an vitro correlation between topoisomerase II active drugs but not between these drugs and ara-C. In vitro ara-C sensitivity (< or = the median of the de novo ANLL at diagnosis) was correlated to poor overall survival (P = 0.02). In vitro sensitivity to daunorubicin and mitoxantrone was associated with prolonged disease free survival (P = 0.03 and P = 0.04). We conclude that despite significant correlation to clinical parameters for daunorubicin and mitoxantrone the predictive value of the ATP assay in this material was insufficient for directing therapy.

Intracellular concentrations of mitoxantrone in leukemic cells in vitro vs in vivo

The aim of this study was to determine the intracellular pharmacokinetics of mitoxantrone in vivo and to use these results to establish how leukemic cells should be incubated to perform clinically relevant in vitro studies of this drug. Blood samples were obtained from 11 patients with acute nonlymphoblastic leukemia at certain intervals up to 20 h after the infusion of mitoxantrone 12 mg/m2. Plasma and leukemic cells were separated and the drug concentrations were determined with HPLC. Before treatment, leukemic cells from 12 patients were incubated with 0.02, 0.05, 0.1, 0.2 and 1.0 microM mitoxantrone for 1-4 h and thereafter cultured in suspension culture for 20 h; during this time cell samples were taken at certain intervals for drug determination. In cells incubated with 0.05 and 0.2 microM mitoxantrone the cytotoxic effect was measured with the DiSC assay after cultivation for 4-5 days. In vivo, the intracellular levels exceeded the plasma concentrations already at the end of infusion and after 2 h the intracellular concentrations were 200-300 times higher than in plasma. In vitro, the intracellular steady state level of mitoxantrone was reached after 1-2 h and there was a pronounced intracellular retention even after 20 h culture in drug-free medium. Incubation with 0.05 microM during 1 h gave intracellular concentrations of mitoxantrone similar to those achieved in vivo. This incubation concentration gave a mean cytotoxic effect of 53% living cells measured with the DiSC assay, which gives good possibilities to discriminate between mitoxantrone-sensitive and unsensitive cells. We believe that exposing leukemic cells in vitro for in vivo mimicking mitoxantrone concentrations could increase the clinical relevance of predictive assays.

Increased incidence of bacteraemia due to viridans streptococci in an unselected population of patients with acute myeloid leukaemia

The aetiology, clinical characteristics and outcome of bacteraemia in patients with acute myeloid leukaemia were studied. All positive blood cultures collected at a haematological ward during 2 7-y periods were evaluated. Altogether, 274 episodes of bacteraemia in 152 patients were recorded, 80 episodes during 1980-86 and 194 during 1990-96. During the 2 periods, trimethoprim-sulfamethoxazol in combination with amikacin was the first-line empirical therapy in patients with neutropaenia and fever. In 1990, antimicrobial prophylaxis with ciprofloxacin and fluconazole was introduced. The incidence of bacteraemia due to viridans streptococci or coagulase-negative staphylococci increased from the first period to the second, whereas the incidence of Enterobacteriaceae decreased. In granulocytopaenic patients during 1990-96, viridans streptococci accounted for 21% of the isolates and in patients treated prophylactically with fluoroquinolone, viridans streptococci accounted for 31%. All viridans streptococci were sensitive to penicillin. At the time of the positive blood cultures, the patients of the second period were granulocytopaenic in 83% of the episodes. The mortality related to septicaemia during the later period was 13% and only 1 of 33 (3%) of the patients with viridans streptococci died. Eight patients (9%) died in relation to septicaemia following curative antileukaemic therapy.

Characterization of an anthracycline-resistant human promyelocyte leukemia (HL-60) cell line with an elevated MDR-1 gene expression

Multidrug resistance to a variety of cytotoxic drugs is due to decreased drug accumulation at the intracellular site of drug action. When due to increased energy-dependent drug efflux, this transport change is often associated with increased expression of an efflux pump for various lipophilic compounds, for example the P-glycoprotein which is the product of the MDR-1 gene. However, previously described HL-60 human promyelocytic leukemia cell lines resistant to the cytotoxic effect of anthracyclines have been reported not to express P-glycoprotein. We have isolated, by drug selection, an anthracycline-resistant HL-60 cell line that, in comparison to parental drug sensitive cells, exhibits a multidrug resistant phenotype including diminished intracellular drug retention, cross-resistance to multiple cytotoxic drugs, increased expression of a monoclonal antibody C219-reactive 180 kDa P-glycoprotein detected by Western blot analysis as well as increased expression of MDR-1 mRNA as determined by Northern blot and solution hybridization/RNAse protection analyses. Evidence is presented that the anthracycline-resistant HL-60 cells have amplified the MDR-1 gene.