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D Diverio

Publications and source records attributed to D Diverio.

At least 37 records · Page 2Linked to original sources

Prolonged molecular remission in advanced acute promyelocytic leukaemia after treatment with gemtuzumab ozogamicin (Mylotarg CMA-676).

We report a patient with acute promyelocytic leukaemia (APL) who received two doses of gemtuzumab ozogamicin for advanced disease. Previous treatments included front-line all-trans retinoic acid and anthracyclines, polychemotherapy consolidation, salvage chemotherapy for the first relapse followed by autologous stem cell transplantation (ASCT), arsenic trioxide for the second relapse followed by a second ASCT and then high-dose methotrexate for more advanced systemic disease with central nervous system involvement. The patient achieved prolonged haematological and molecular remission after monotherapy with gemtuzumab ozogamicin given at the time of the third relapse.

Adult↗

Variability in the levels of PML-RAR alpha fusion transcripts detected by the laboratories participating in an external quality control program using several reverse transcription polymerase chain reaction protocols.

BACKGROUND AND OBJECTIVES: The detection of PML-RAR by reverse transcription (RT) polymerase chain reaction (PCR) in acute promyelocytic leukemia (APL) patients who are in hematologic remission influences therapeutic decision making in several trials. In the light of this, the Spanish group has recently designed an external quality assessment program (EQAP) of RT-PCR detection of PML-RAR, which includes a study of sensitivity of the participating laboratories. DESIGN AND METHODS: Eighteen laboratories were involved in the program. Ten laboratories followed the method of Biondi et al., 5 employed that of Borrow et al. and the 3 remaining used other protocols. The sensitivity was studied in five rounds of quality control. The first two shipments consisted of dilutions of NB4 RNA into non-APL RNA. The third round consisted of serial dilutions of the NB4 cell line into HL60 cells. The fourth and five rounds consisted of plasmid dilutions containing the bcr1 and bcr3 PML-RAR isoforms. RESULTS: The results showed that the distinct methods allow detection of the PML-RAR hybrid up to a dilution of 10(-4), and exceptionally, up to 10(-5). The laboratories following the method of Biondi et al. usually detected the 10(-3) dilution and less frequently the 10(-4) one, whereas those using other methods usually detected PML-RAR transcript in the 10(-4) dilution, and less commonly in the 10(-5) dilution. However, each of the PCR methods used by EQAP participating laboratories successfully detected at least 50 copies of PML-RAR alpha fusion transcript in plasmid dilution controls. INTERPRETATION AND CONCLUSIONS: The results point to heterogeneous sensitivity amongst participating laboratories. This may reflect differences in methodology, although variations in sample quality may also account for discrepant findings.

Humans↗

Use of dual-color interphase FISH for the detection of inv(16) in acute myeloid leukemia at diagnosis, relapse and during follow-up: a study of 23 patients.

The value of dual-color fluorescence in situ hybridization (FISH) for the detection of inv(16), using two contigs of cosmid probes mapping on both sides of the chromosome 16p breakpoint region, was evaluated in 23 acute myeloid leukemias (AML) in different phases of the disease. At diagnosis interphase FISH detected inv(16) in 19/19 (100%) cases with conventional cytogenetics (CC) evident aberration and excluded the rearrangement in two patients with CC suspected inv(16). Moreover, it also identified an associated del(16p) in two patients. At relapse, it revealed the inv(16) in 8/8 (100%) studied cases. These results were concordant with those of reverse transcriptase-polymerase chain reaction (RT-PCR). From 13 patients who obtained at least one complete remission (CR), 31 follow-up samples were analyzed using interphase FISH. Twenty-nine specimens scored negative for inv(16) and two were positive. RT-PCR detected CBFbeta/MYH11 transcripts in four of the nine CR samples analyzed, being more sensitive than interphase FISH. Eight of the 13 patients relapsed at a median time of 6.5 months (range 1-15) from the last negative FISH analysis. Of the two patients with positive FISH in CR, one relapsed soon after. At diagnosis and relapse, interphase-FISH proved to be an effective technique for detecting inv(16) appearing more sensitive than CC. Prospective studies with more frequent controls and possibly additional FISH probes are needed to assess the value of interphase FISH for minimal residual disease (MRD) and relapse prediction.

Acute Disease↗

HLA class I in acute promyelocytic leukemia (APL): possible correlation with clinical outcome.

The majority of patients with acute promyelocytic leukemia (APL) possess either a bcr1 or a bcr3 type fusion between PML and RARalpha genes. The junction sequences may possibly be a target for immune response and influence susceptibility to the disease. In this case, HLA class I allele frequencies would be different between bcr1 and bcr3 patients. To test this hypothesis, we typed 102 APL patients for HLA-A, -B and -Cw alleles. The A*1, A*30, B*51, B*41, Cw*0602, and Cw*1701 alleles showed a different distribution between bcr1 and bcr3 patients, but in no case was this statistically significant after correction for the number of comparisons or was confirmed in an independent panel. Moreover, no difference was detected between bcr1 and bcr3 when HLA alleles were grouped according to their peptide binding specificities. Comparing HLA frequencies, clinical features at diagnosis and clinical outcome of the 64 patients homogeneously treated with all-trans retinoic acid and idarubicin (AIDA protocol) we observed a statistically significant association between HLA-B*13 and risk of relapse by univariate and multivariate regression analysis. Should this finding be confirmed in larger future studies, this observation would be of outmost importance in identifying patients at high risk of relapse in which more aggressive consolidation therapies should be used.

Adult↗

Therapy of molecular relapse in acute promyelocytic leukemia.

Fourteen patients with PML/RARalpha-positive acute promyelocytic leukemia (APL) were given salvage therapy at the time of first molecular relapse. All patients had achieved first molecular remission after the AIDA protocol (all-trans retinoic acid [ATRA] + idarubicin) and were being prospectively monitored by reverse transcriptase-polymerase chain reaction (RT-PCR). Molecular relapse was defined as reappearance of RT-PCR-positivity for the PML/RARalpha fusion (sensitivity 10(-4)) in 2 successive marrow samples collected during postconsolidation monitoring. The median duration of first molecular remission was 7.5 months (range, 2 to 25). Salvage therapy consisted of oral ATRA for 30 days followed by 4 daily courses of chemotherapy (CHT) with cytarabine 1 g/m(2)/d and mitoxantrone 6 mg/m(2)/d. Second molecular remission was obtained in 12 of 14 patients (86%). Seven of these 12 attained molecular remission after ATRA alone. Of the 2 patients who persisted PCR(+) after CHT, 1 died in remission and 1 progressed to hematologic relapse. Of 12 patients PCR(-), 8 received consolidation with autologous bone marrow transplantation (ABMT), and 4 received ATRA-containing maintenance. Ten patients in this group are in sustained second molecular remission at a median time of 9.5+ months (range, 4 to 22+) and 2 underwent hematologic relapse 6 and 13 months, respectively, after transient second molecular remission. The 2-year Kaplan and Meier survival estimate from time of relapse was 92% (95% confidence interval [CI]: 61% to 98%) in this series, and 44% (95% CI: 35% to 52%) in a previous series of 37 patients who received the same treatment at the time of hematologic recurrence (P <.05, by log-rank test). This study suggests that early administration of salvage therapy is advantageous in APL and represents the first experience on therapy of molecular relapse in acute leukemia.

Adult↗

Caspases mediate retinoic acid-induced degradation of the acute promyelocytic leukemia PML/RARalpha fusion protein.

All-trans-retinoic acid (RA) treatment induces morphological remission in acute promyelocytic leukemia (APL) patients carrying the t(15;17) and expressing the PML/RARalpha product by inducing terminal differentiation of the leukemic clone. RA treatment induces downregulation of PML/RARalpha and reorganization of the PML-nuclear bodies. These events have been proposed to be essential for the induction of APL cell differentiation by RA. Here, we show that in the APL-derived NB4 cell line as well as in myeloid precursor U937 cells expressing the PML/RARalpha (U937/PR9) and in blasts from APL patients, the PML/RARalpha fusion protein is cleaved by a caspase 3-like activity induced by RA treatment. In fact, a caspase 3-like activity is detectable in PML/RARalpha expressing cells after RA treatment, and selective caspase inhibitor peptides are able to prevent the RA-induced degradation of the fusion protein in vivo and in vitro. Using recombinant caspases and PML/RARalpha deletion mutants we mapped a caspase 3 cleavage site (Asp 522) within the alpha-helix region of the PML component of the fusion protein. The extent of PML/RARalpha cleavage directly correlates with the ability of RA to restore the normal PML nuclear bodies (NBs) pattern. However, RA-induced differentiation is not prevented by the persistence of the fusion product and occurs in the absence of normally structured PML NBs. These results indicate that PML/RARalpha is directly involved in conferring RA sensitivity of APL cells and that the RA-induced reassembly of PML NBs is the consequence of the disappearance of PML/RARalpha.

Antineoplastic Agents↗

Early detection of relapse by prospective reverse transcriptase-polymerase chain reaction analysis of the PML/RARalpha fusion gene in patients with acute promyelocytic leukemia enrolled in the GIMEMA-AIEOP multicenter "AIDA" trial. GIMEMA-AIEOP Multicenter "AIDA" Trial.

Although the majority of patients with acute promyelocytic leukemia (APL) are potentially cured by treatments combining all-trans retinoic acid (ATRA) and chemotherapy (CHT), a sizable proportion (around 30%) will relapse during follow-up. Retrospective molecular monitoring studies using reverse transcriptase-polymerase chain reaction (RT-PCR) for the specific PML/RARalpha fusion gene, have shown that a positive test usually precedes the occurrence of hematologic relapse. Prospective RT-PCR analyses were performed since 1993 at diagnosis and at preestablished time intervals during follow-up in bone marrow (BM) samples of 163 patients with PML/RARalpha+ APL enrolled in the multicenter Gruppo Italiano Malattie Ematologiche Maligne dell' Adulto (GIMEMA) trial AIDA (All-trans retinoic acid plus Idarubicin). Treatment consisted of ATRA and idarubicin for induction followed by three polychemotherapy courses as consolidation. The sensitivity level of the RT-PCR assay for PML/RARalpha, as assessed by serial dilution experiments, was 10(-4). All patients were in hematologic remission and tested PCR- at the end of consolidation. Of 21 who converted to PCR-positive thereafter, 20 underwent hematologic relapse at a median time of 3 months (range, 1 to 14) from the first PCR+ result. Seventeen of these 21 (81%) PCR+ conversions were recorded within the first 6 months postconsolidation. Of 142 who tested persistently PCR- in >/=2 tests after consolidation, 8 had hematologic relapse and 134 remained in complete remission (CR) after a median follow-up of 18 months (range, 6 to 38) postconsolidation. Using a time-dependent Cox model, the relative risk of hematologic relapse of patients who converted to PCR+ was 31.8 (confidence limits 95%, 12.9 to 78.3). Our results indicate that conversion to PCR positivity for PML/RARalpha during remission is highly predictive of subsequent hematologic relapse and highlight the prognostic value of stringent molecular monitoring during the early postconsolidation phase in APL. As a result of the present study, salvage treatment in patients enrolled in the GIMEMA trial AIDA is now anticipated at the time of molecular relapse, defined as the conversion to PCR positivity in two successive BM samplings during follow-up.

Adolescent↗

The PML/RARalpha fusion protein inhibits tumor necrosis factor-alpha-induced apoptosis in U937 cells and acute promyelocytic leukemia blasts.

We investigated the effect of the acute promyelocytic leukemia (APL) specific PML/RARalpha fusion protein on the sensitivity to TNF-alpha-mediated apoptosis. The U937 leukemia cell line was transduced with PML/RARalpha cDNA. PML/RARalpha expression caused a markedly reduced sensitivity to TNF-alpha, even if apoptosis was triggered by agonistic antibodies to TNF-alpha receptors I and II (TNF-alphaRI, II). PML/RARalpha induced a 10-20-fold decrease of the TNF-alpha-binding capacity via downmodulation of both TNF-alphaRI and TNF-alphaRII: this may mediate at least in part the reduced sensitivity to TNF-alpha. Furthermore, the fusion protein did not modify Fas expression (CD95) or sensitivity to Fas-mediated apoptosis. The pathophysiological significance of these findings is supported by two series of observations. (a) Fresh APL blasts exhibit no TNF-alpha binding and are resistant to TNF-alpha-mediated apoptosis. Conversely, normal myeloblasts-promyelocytes show marked TNF-alphaR expression and are moderately sensitive to TNF-alpha-mediated cytotoxicity. Similarly, blasts from other types of acute myeloid leukemia (AML M1, M2, and M4 FAB types) show an elevated TNF-alpha binding. (b) The NB4 APL cell line, which is PML/RARalpha+, shows low TNF-alphaR expression capacity and is resistant to TNF-alpha-triggered apoptosis; conversely a PML/RARalpha- NB4 subclone (NB4.306) exhibits detectable TNF-alpha-binding capacity and is sensitive to TNF-alpha-mediated cytotoxicity. These studies indicate that the PML/RARalpha fusion protein protects against TNF-alpha-induced apoptosis, at least in part via downmodulation of TNF-alphaRI/II: this phenomenon may play a significant role in APL, which is characterized by prolonged survival of leukemic blasts.

Antigens, CD↗

Preliminary experience in external quality control of RT-PCR PML-RAR alpha detection in promyelocytic leukemia.

To standardize the results obtained in PML/RAR alpha RT-PCR detection by laboratories of hospitals involved in the Spanish Program for Treatment of Hematological Malignancies (PETHEMA) LPA-96, designed for the treatment of acute promyelocytic leukemia (APL), cDNA samples obtained by reverse transcription of RNA from bone marrow samples of patients with APL were sent to participating laboratories. During the first year of this external quality assessment trial nine samples were tested by a maximum of 12 laboratories. The control gene was satisfactorily amplified in 90% of the samples (62 of 69 samples), supporting the adequacy of the cDNA to be used as control sample. There was an 83% concordance between laboratories for PML/RAR alpha detection with similar results for the type of PML/RR alpha rearrangements. However, 17% disagreement still remained, attributable to low sensitivity or inadequacy of methods followed. The results stressed the need for implementation of an external quality assessment scheme to ensure the standardization of the results.

Gene Amplification↗

Immunophenotype of adult and childhood acute promyelocytic leukaemia: correlation with morphology, type of PML gene breakpoint and clinical outcome. A cooperative Italian study on 196 cases.

Acute promyelocytic leukaemia (APL), characterized by a specific PML-RARalpha fusion gene resulting from translocation t(15;17) and by a high response rate to differentiation therapy with all-trans retinoic acid, presents clinical (varying WBC counts, age and treatment outcome), morphological (hypergranular M3 and hypogranular M3V) and molecular (three isoforms of PML breakpoint) heterogeneity. We correlated leukaemic immunophenotype with these aspects in 196 molecularly confirmed APLs (63 children and 133 adults) in Italy. The bcr3 isoform (P = 0.05) and FAB M3V (P = 0.05) were more frequent in children. We confirmed in APL an immunophenotype characterized by frequent expression of CD13, CD33 and CD9 and rare expression of HLA-DR, CD10, CD7 and CD11b. However, we recognized CD2 in 28%, CD34 in 23% and CD19 in 11% of cases and demonstrated by double labelling that CD34 and CD2 may be co-expressed. CD2, CD34 and CD19 were significantly intercorrelated, and variably associated to other features: CD2 and CD34 with PML bcr3 (P < 0.001 and P < 0.001, respectively) and with M3V (P < 0.001 and P = 0.002), whereas only CD19 was directly correlated with WBC counts and only CD2 positively influenced CR rate (logistic model) and event-free survival (Cox model). We conclude that immunophenotype plays a role in the determination of the biological and clinical heterogeneity of childhood and adult APL.

Adolescent↗

Disappearance of PML/RAR alpha acute promyelocytic leukemia-associated transcript during consolidation chemotherapy.

BACKGROUND AND OBJECTIVE: Acute promyelocytic leukemia (APL) (M3 according to FAB classification) is a subtype of acute myelogenous leukemia characterized by a specific t(15;17) (q22;q12) chromosomal translocation. The majority of APL patients achieve morphologic remission after induction chemotherapy. They can be followed from this point by cytogenetic and molecular analysis of the persistence of the PML/RAR alpha transcript. In order to determine the influence of successive courses of consolidation chemotherapy on clinical and molecular outcome, APL patients treated with all-trans retinoic acid (ATRA) and chemotherapy (AIDA-GIMEMA-LAP0493 protocol) were investigated. DESIGN AND METHODS: Twenty-four APL patients (pts) (15 males; 9 females) were studied by RT-PCR and cytogenetic analysis at diagnosis, after induction chemotherapy, at each point after any of three consolidation courses, and every 3 months during the first years of maintenance therapy. The median follow-up was 24 months (mths) (range 7-40 mths). RESULTS: All pts achieved hematologic remission after induction chemotherapy. Our results demonstrate that the majority (87%) of APL patients were still molecularly positive for the APL associated transcript after induction chemotherapy, while the majority (80%) of APL patients became PCR-after the second consolidation chemotherapy. INTERPRETATION AND CONCLUSIONS: The role of the third consolidation chemotherapy course in converting patients with persistent molecular evidence of disease from PCR+ to PCR- was minimal. We confirm the validity of molecular follow-up after single courses of chemotherapy in monitoring the role of molecular remission.

Adolescent↗

Immunocytochemical diagnosis of acute promyelocytic leukemia (M3) with the monoclonal antibody PG-M3 (anti-PML).

Acute promyelocytic leukemia (APL) is characterized by a reciprocal 15; 17 chromosomal translocation, which fuses the promyelocytic leukemia (PML) and retinoic acid receptor alpha (RARalpha) genes, leading to the expression of the PML/RARalpha fusion oncoprotein. Immunocytochemical labeling of the wild-type PML protein with the PG-M3 monoclonal antibody (MoAb) directed against the amino terminal portion of the human PML gene product, produces a characteristic nuclear speckled pattern that is due to localization of the protein into discrete dots (5 to 20 per nucleus), named PML nuclear bodies. The architecture of PML nuclear bodies appears to be disrupted in APL cells that bear the t(15; 17), thus resulting in a change of the nuclear staining pattern from speckled (wild-type PML protein) to microgranular (PML-RARalpha fusion protein). To assess whether the PG-M3 MoAb could assist in the diagnosis of APL (M3), bone marrow and/or peripheral blood samples from 100 cases of acute nonlymphoid leukemias of different subtypes were blindly immunostained with the PG-M3 MoAb, using the immunoalkaline phosphatase (APAAP) or immunofluorescence technique as detection system. Notably, the abnormal (micropunctate) pattern of the PML/RARalpha fusion protein (usually >/=50 small granules/per nucleus) was observed in APL (M3) samples, but not in other types of acute nonlymphoid leukemias. Immunocytochemical labeling with PG-M3 was particularly useful in the diagnosis of microgranular variant of APL (M3V) (three cases misdiagnosed as M4 and M5), and also to exclude a morphologic misdiagnosis of APL (six of 78 cases). In all cases investigated, immunocytochemical results were in agreement with those of reverse transcription-polymerase chain reaction (RT-PCR) for PML/RARalpha. Because the epitope identified by PG-M3 is located in the aminoterminal portion of PML (AA 37 to 51), the antibody was suitable for recognizing APL cases characterized by breakpoint occurring at different sites of PML (bcr 1, bcr 2 and bcr 3). In conclusion, immunocytochemical labeling with PG-M3 represents a rapid, sensitive, and highly-specific test for the diagnosis of APL that bears the t(15; 17). This should allow an easy and correct diagnosis of this subtype of acute leukemia to any laboratory provided with a minimal equipment for immunocytochemistry work.

Adolescent↗

Molecular remission in PML/RAR alpha-positive acute promyelocytic leukemia by combined all-trans retinoic acid and idarubicin (AIDA) therapy. Gruppo Italiano-Malattie Ematologiche Maligne dell'Adulto and Associazione Italiana di Ematologia ed Oncologia Pediatrica Cooperative Groups.

Two hundred fifty-three patients with newly diagnosed acute promyelocytic leukemia (APL) were eligible to enter the multicentric GIMEMA-AIEOP "AIDA" trial during the period July 1993 to February 1996. As a mandatory prerequisite for eligibility, all patients had genetic evidence of the specific t(15;17) lesion in their leukemic cells confirmed by karyotyping or by reverse transcription-polymerase chain reaction (RT-PCR) of the PML/RAR alpha fusion gene (the latter available in 247 cases). Median age was 37.8 years (range, 2.2 to 73.9). Induction treatment consisted of oral all-trans retinoic acid (ATRA), 45 mg/m2/d until complete remission (CR), given with intravenous Idarubicin, 12 mg/m2/d on days 2, 4, 6, and 8. Three polychemotherapy cycles were given as consolidation. Hematologic and molecular response by RT-PCR was assessed after induction and after consolidation. At the time of analysis, 240 of the 253 eligible patients were evaluable for induction. Of these, 11 (5%) died of early complications and 229 (95%) achieved hematologic remission. No cases of resistant leukemia were observed. Of 139 cases studied by RT-PCR after induction, 84 (60.5%) were PCR-negative and 55 (39.5%) PCR-positive. One hundred sixty-two patients were evaluable by RT-PCR at the end of consolidation. Of these, 159 (98%) tested PCR-negative and 3 (2%), PCR-positive. After a median follow up of 12 months (range, 0 to 33), the estimated actuarial event-free survival for the whole series of 253 eligible patients was 83% +/- 2.6% and 79% +/- 3.2% at 1 and 2 years, respectively. This study indicates that the AIDA protocol is a well-tolerated regimen that induces molecular remission in almost all patients with PML/RAR alpha-positive APL. Preliminary survival data suggest that a remarkable cure rate can be obtained with this treatment.

Adolescent↗

Characterization of the retinoid binding properties of the major fusion products present in acute promyelocytic leukemia cells.

The bcr1- and bcr3- promyelocytic leukemia/retinoic acid receptor alpha (PML/RAR alpha) are the two major fusion proteins expressed in acute promyelocytic leukemia (APL) patients. These proteins, which are present in different lengths of PML (amino acids 1-552 and 1-394, respectively), contain most of the functional domains of PML and RAR alpha, bind all-trans-retinoic acid (t-RA), and act as t-RA-dependent transcription factors. T-RA is an effective inducer of clinical remission only in patients carrying the t(15;17) and expressing the PML/RAR alpha products. However, in APL patients achieving complete remission with t-RA therapy the bcr3-PML/RAR alpha product has been found associated with a poorer prognosis than bcr1-PML/RAR alpha. In the present study we have investigated the structural and functional properties of the bcr3-PML/RAR alpha in comparison to the previously characterized bcr1-PML/RAR alpha. In particular, we have measured the binding properties of the two endogenous ligands t-RA and 9-cis-RA to both of these isoforms. T-RA binding analysis of nuclear and cytosolic extracts prepared from bcr3-PML/RAR alpha APL patients and from bcr3-PML/RAR alpha COS-1 transfected cells indicates that this protein is present only as high-molecular-weight nuclear complexes. Using saturation binding assays and Scatchard analyses we found that t-RA binds with slightly less affinity to the bcr3-PML/RAR alpha receptor than to bcr1-PML/RAR alpha or RAR alpha (Kd = 0.4 nmol/L, 0.13 nmol/L or 0.09 nmol/L, respectively). Moreover, two different high-affinity 9-cis-RA binding sites (Kd = 0.45 and 0.075 nmol/L) were detectable in the bcr3-PML/RAR alpha product but not in the bcr1-PML/RAR alpha product (Kd = 0.77 nmol/L). By competition binding experiments we showed that 9-cis-RA binds with higher specificity to the bcr3-PML/RAR alpha isoform than to the bcr1-PML/RAR alpha or RAR alpha. Consistent with these data, the binding of 9-cis-RA to the bcr3-PML/RAR alpha product resulted in increased transcriptional activation of the RA-responsive element (RARE) TRE, but not of the betaRARE, in transiently transfected COS-1 cells. These results provide evidence indicating that preferential retinoid binding to the different PML/RAR alpha products can be measured.

Alitretinoin↗

Autologous bone marrow transplantation for acute promyelocytic leukemia in second remission: prognostic relevance of pretransplant minimal residual disease assessment by reverse-transcription polymerase chain reaction of the PML/RAR alpha fusion gene.

Reverse-transcription polymerase chain reaction (RT-PCR) of the PML/RAR alpha fusion gene may predict relapse in acute promyelocytic leukemia (APL) patients in hematologic complete remission (CR). We have prospectively studied by RT-PCR 15 PML/RAR alpha+ APL patients undergoing autologous bone marrow transplantation (ABMT) in second CR. The median time of first CR duration was 12 months (range, 6 to 40). All patients were reinduced with all-trans retinoic acid (ATRA), followed in 12 of 15 cases by mitoxantrone and Ara-C as consolidation. Fourteen patients received the BAVC (BCNU, Ara-C, m-AMSA, and VP-16) schedule as conditioning regimen. Unpurged marrows were collected immediately before conditioning treatment, analyzed by RT-PCR, and reinfused at median of 2 months (range, 2 to 7) from the achievement of second CR. Seven patients were PCR+ and eight PCR for PML/RAR alpha in their pretransplant marrows. All seven patients of the former group remained PCR+ during the follow-up and relapsed at a median time of 5 months (range, 2 to 9) from ABMT and 9 months (range, 4 to 14) from second CR. Of the eight PCR- patients, all remained PCR- during the follow-up controls. One patient relapsed at 10 months from ABMT, one died of a secondary (PML/RAR alpha-) leukemia, and six are in hematologic and molecular remission at a median time of 28 months (range, 15 to 60) after ABMT and 32 months (range, 17 to 62) from second CR. Our results indicate that, in APL patients in second CR, ABMT with PML/RAR alpha- marrow cells is likely to result in prolonged clinical and molecular remissions. Conversely, patients who test PCR+ after reinduction necessitate the use of alternative aggressive approaches, including unrelated allogeneic transplant.

Adolescent↗

The role of all-trans-retinoic acid (ATRA) treatment in newly-diagnosed acute promyelocytic leukemia patients aged > 60 years.

BACKGROUND: To evaluate the role and toxicity of ATRA therapy in newly-diagnosed APL patients aged > 60 yrs, the outcome of 16 consecutive elderly APL patients observed between January 1990 and June 1996 were analyzed. PATIENTS AND METHODS: Their median age was 65.5 yrs (range 60-81 years), the male/female ratio was 7:9, and molecular biology analysis showed a PML/RARa rearrangement in all patients. Seven patients had a concomitant cardiovascular disease. ATRA 45 mg/sqm/day was given to all patients, and in 11 was associated with idarubicin (AIDA protocol); in two patients ATRA was associated with mitoxantrone + ara-C, while the remaining three patients received ATRA alone. RESULTS: Fourteen patients (87.5%) achieved CR, and two patients (12.5%) died during induction. Despite the high CR rate, eight episodes of severe cardiovascular complication were observed in seven patients, three of whom had previously had cardiovascular disease; in addition, three patients had sepsis (two bacterial and one fungal). As of 31 March 1997, 9 of 14 patients were still in first CR after a 19-month (range 7-64 months) median follow-up since attainment of the CR. One patient died in CR of a fungal complication and four patients relapsed after 8, 9, 23 and 35 months following CR: two of them achieved a second CR lasting seven and +15 months with ATRA alone. Of the nine patients still in first CR, only three have received the planned consolidation therapy and five have been in CR for more than 24 months (+25, +33, +34, +38, +63). CONCLUSIONS: Despite the fact that most of these patients received shorter consolidation treatments than do younger patients, the good results achieved in them might be considered an indication for modifying treatment schedules in order to reduce severe toxicity and improve protocol compliance.

Aged↗