Biomedical subjects

Francis J Giles

Publications and source records attributed to Francis J Giles.

At least 73 records · Page 4Linked to original sources

PubMed2004

Telomerase activity is not a prognostic factor in chronic lymphocytic leukemia.

We measured telomerase activity (TA) in bone marrow samples from 214 patients with CLL and correlated it with patients' characteristics and survival. In >50% of cases (126/214; 59%) no detectable TA was found. There was no difference in TA between previously treated (n = 153) and untreated (n = 61) patients (P = 0.4), or patients with various Rai (0-IV) stages (P = 0.85). TA correlated significantly with white blood cell and lymphocyte count (P = 0.02 and 0.01, respectively) but not with bone marrow cellularity, beta2-microglobulin (beta2M), or other patient characteristics. Patients who had no TA had slightly lower beta2M and lower lymphocyte counts (P = 0.5 and 0.04, respectively) as compared with patients with detectable TA. However, there was no correlation between TA and survival. This data suggests that TA may not play a significant role in the clinical behavior of CLL.

Adult↗

PubMed2004

Alemtuzumab: validation of a sensitive and simple enzyme-linked immunosorbent assay.

Alemtuzumab (MabCampath) is a humanized rat monoclonal antibody that targets the CD52 antigen. It has been approved for the treatment of patients with resistant chronic lymphocytic leukaemia (CLL). Measuring plasma/serum levels of alemtuzumab is important for optimizing the dosing and scheduling of therapy; however, current assays in serum or plasma, based on the capture of alemtuzumab using CD52, are complicated and difficult to adapt for high throughput testing. We developed a simple sandwich enzyme-linked immunosorbent assay (ELISA) to measure alemtuzumab that takes advantage of the remaining rat sequence in alemtuzumab. Using specific anti-rat immunoglobulin (Ig) antibodies (absorbed against human Ig), alemtuzumab levels were measured in the serum and plasma of patients treated with alemtuzumab. Levels were similar between plasma and serum samples, in fresh samples and samples stored at 4 degrees C for 24 h, but were significantly lower in samples stored at room temperature for 24h. The assay was successfully used to determine serum alemtuzumab pre- and post-treatment. This assay is simple and adaptable for high throughput testing, with a limit of detection of 0.05 microg/ml and a coefficient of variation of +/-12.5%. No false positivity was observed in >200 samples tested. This validated assay should help optimize the dosing and scheduling of alemtuzumab therapy. The underlying principles are also applicable to the measurement of other humanized antibodies using an appropriate anti-Ig.

Alemtuzumab↗

PubMed2004

In vitro evaluation of cytochrome P450-mediated drug interactions between cytarabine, idarubicin, itraconazole and caspofungin.

PURPOSE: Antifungal prophylaxis is an important component of induction therapy for patients with acute myeloid leukemia (AML). Azole antifungal agents are increasingly used in this context. In vitro assays were performed to assess whether cytochrome P450 (CYP450) enzymes were affected by combinations of cytarabine or idarubicin with itraconazole or caspofungin. METHODS: The high throughput microtiter assay was used to determine whether cytarabine, idarubicin and itraconazole or caspofungin were CYP450 isoenzyme substrates, inhibitors of CYP450 isoenzymes, and to determine potential CYP450 metabolism interactions between these agents. RESULTS: Idarubicin is a substrate for CYP450 2D6 and 2C9. Cytarabine is a substrate of CYP450 3A4. Idarubicin inhibits CYP450 2D6, and cytarabine, itraconazole, and caspofungin inhibit CYP450 3A4. Cytarabine metabolism was significantly decreased when combined with caspofungin or itraconazole. CONCLUSIONS: The inhibition of cytarabine metabolism may have important clinical implications. These in vitro findings warrant investigation with in vivo pharmacokinetic studies.

Acute Disease↗

PubMed2004

Troxacitabine and imatinib mesylate combination therapy of chronic myeloid leukaemia: preclinical evaluation.

The in vitro and in vivo activity of a deoxycytidine analogue, troxacitabine, alone or in combination with imatinib mesylate (IM), was evaluated against human chronic myeloid leukaemia (CML) cell lines both sensitive (KBM5 and KBM7) and resistant (KBM5-R and KBM7-R) to IM. These cell lines differ in their sensitivity to IM but all showed similar sensitivity to treatment with troxacitabine (IC50 = 0.5-1 micromol/l). Combined treatment with troxacitabine and IM revealed additive or synergistic effects. Greater apoptotic response was seen with combined treatment than with either agent alone in KBM7-R cells. In clonogenic assays, troxacitabine showed activity against mononuclear cells from CML patients (IC50 = 0.01 micromol/l) with either IM-sensitive or resistant disease. In vivo efficacy studies were carried out in severe combined immunodeficient mice bearing KBM5 or KBM5-R cells. Troxacitabine was administered i.p. daily for 5 d starting on day 20, at doses of 5, 10, 20, or 25 mg/kg. IM was administered i.p. twice a day for 10 d at a dose of 50 mg/kg starting on day 25. In this setting of late stage disease, troxacitabine led to a significant increase in life span, while IM did not. When IM was combined with troxacitabine at 10 and 25 mg/kg in the KBM5 xenograft model, a further increase in life span was observed and some mice achieved long-term survival. These data indicate that the combination of troxacitabine and IM has significant preclinical activity in advanced CML and that clinical evaluation of this combination is warranted.

Animals↗

PubMed2004

An update on the management of chronic lymphocytic leukaemia.

Despite the lack of long-term survival data, the impressive results obtained with fludarabine- and rituximab-based therapies have altered the philosophy of the management of patients with chronic lymphocytic leukaemia (CLL). Therapy with chemoimmunotherapy appears to give higher responses with more patients achieving complete remission and some molecular remission. This may potentially translate into improved disease-free survival, and potentially a 'cure'. Treatment options for patients who develop resistance to fludarabine continue to be limited. This review summarises current chemo-, immuno-, and chemoimmunotherapeutic regimens that are being currently evaluated in patients with CLL.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2004

Novel therapies for patients with chronic myeloid leukemia.

The most immediate issues that will have a major impact on the long-term survival of patients with chronic myeloid leukemia is the optimal use of imatinib mesylate (Gleevec, Novartis) and the development of effective therapies for those patients who are intolerant of, or become resistant to, optimal doses of this agent. Of the multiple new agents that are currently being developed for patients with chronic myeloid leukemia, most are being investigated in patients who have developed resistance to imatinib, which is a confounding factor in itself. The mechanisms of action of novel agents are diverse and they may have a variably synergistic therapeutic relationship with imatinib. The complete blockade of the intracellular pathways that are triggered by Bcr-Abl, combined with successful reversal of apoptotic and/or angiogenic abnormalities in chronic myeloid leukemia, may well lead to a cure for the majority of patients.

Animals↗

PubMed2003

Imatinib mesylate therapy improves survival in patients with newly diagnosed Philadelphia chromosome-positive chronic myelogenous leukemia in the chronic phase: comparison with historic data.

BACKGROUND: The International Randomized study of Interferon-alpha plus cytarabine (IFN-alpha plus ara-C) versus STI571 (imatinib mesylate) [IRIS trial] in patients with newly diagnosed Philadelphia chromosome (Ph)-positive, chronic-phase chronic myelogenous leukemia (CML) has not shown (to date) a survival advantage for imatinib. This was most likely because approximately 90% of patients receiving IFN-alpha plus ara-C changed to imatinib therapy after a median of 8 months into therapy. METHODS: The authors analyzed the results with imatinib therapy in patients with newly diagnosed Ph-positive CML in chronic phase and compared their outcome with patients who received IFN-alpha regimens. A total of 187 patients with Ph-positive CML in early chronic phase treated with imatinib were compared with a historic group of 650 similar patients treated with IFN-alpha regimens from 1982 until 1997. RESULTS: Patients who received imatinib were significantly older and had significantly more bone marrow basophilia and less leukocytosis. The complete cytogenetic response (Ph 0%) rates were better with imatinib (81% vs. 32%; P < 0.001), as were the survival rates (30-month estimated survival rates 98% vs. 88%; P = 0.01). A multivariate analysis of the total study group of 837 patients identified imatinib therapy to be a significant independent favorable prognostic factor for survival (P = 0.01). CONCLUSIONS: The current study is the first to indicate the survival advantage of imatinib compared with IFN-alpha, the previous standard of care, in patients with early chronic-phase CML.

Administration, Oral↗

PubMed2003

Alemtuzumab as treatment for residual disease after chemotherapy in patients with chronic lymphocytic leukemia.

BACKGROUND: The objective of this study was to investigate the efficacy and safety of alemtuzumab, the humanized anti-CD52 monoclonal antibody, in patients with B-cell chronic lymphocytic leukemia and residual disease after chemotherapy. METHODS: Forty-one patients received alemtuzumab 3 times weekly for 4 weeks. The first 24 patients received 10 mg per dose, and the next 17 patients received 30 mg. All patients received infection prophylaxis during therapy and for 2 months after treatment. RESULTS: The overall response rate was 46%, including 39% of patients who received the 10 mg dose and responded versus 56% of the patients who received the 30 mg dose. The major reason for failure to respond was the presence of adenopathy. Residual bone marrow disease cleared in most patients, and 11 of 29 patients (38%) achieved a molecular disease remission. The median time to disease progression had not been reached in responders with a median follow-up of 18 months. Six patients remained in disease remission between 24-38 months after therapy. Infusion-related events were common with the initial doses, but all such events were NCI Common Toxicity Criteria Grade 1-2. Infections were reported to occur in 15 patients (37%), and 9 of these infections were reactivation of cytomegalovirus. Three patients developed Epstein-Barr virus positive, large cell lymphoma. Two patients had spontaneous resolution of the lymphoma and, in one patient, the lymphoma resolved after treatment with cidofovir and immunoglobulin. CONCLUSIONS: Alemtuzumab produced significant responses in patients with residual disease after chemotherapy. Bone marrow disease was eradicated more frequently than lymph node disease, and molecular disease remissions were achieved. A randomized trial comparing alemtuzumab with observation after chemotherapy is indicated.

Adult↗

PubMed2003

Phase 1 study of low-dose prolonged exposure schedules of the hypomethylating agent 5-aza-2'-deoxycytidine (decitabine) in hematopoietic malignancies.

Decitabine (5-aza-2'-deoxycytidine) inhibits DNA methylation and has dual effects on neoplastic cells, including the reactivation of silenced genes and differentiation at low doses and cytotoxicity at high doses. We evaluated, in a phase 1 study, low-dose prolonged exposure schedules of decitabine in relapsed/refractory leukemias. Patient cohorts received decitabine at 5, 10, 15, or 20 mg/m2 intravenously over one hour daily, 5 days a week for 2 consecutive weeks, doses 5- to approximately 30-fold lower than the maximum tolerated dose (MTD). There were 2 groups that also received 15 mg/m2 daily for 15 or 20 days. A total of 50 patients were treated (44 with acute myelogenous leukemia [AML]/myelodysplasia [MDS], 5 with chronic myelogenous leukemia [CML], and 1 with acute lymphocytic leukemia [ALL]), and the drug was well tolerated at all dose levels, with myelosuppression being the major side effect. Responses were seen at all dose levels. However, the dose of 15 mg/m2 for 10 days appeared to induce the most responses (11 of 17 or 65%), with fewer responses seen when the dose was escalated or prolonged (2 of 19 or 11%). There was no correlation between P15 methylation at baseline or after therapy and response to decitabine. We conclude that decitabine is effective in myeloid malignancies, and low doses are as or more effective than higher doses.

Adolescent↗

PubMed2003

Treatment of Philadelphia chromosome-positive acute lymphocytic leukemia with hyper-CVAD and imatinib mesylate.

Imatinib mesylate, an inhibitor of the Bcr-Abl tyrosine kinase, has modest activity in refractory/relapsed Philadelphia chromosome (Ph)-positive acute lymphocytic leukemia (ALL). Use of concurrent chemotherapy and imatinib mesylate in newly diagnosed Ph-positive ALL was explored. There were 20 patients who received hyper-CVAD (cyclophosphamide, vincristine, Adriamycin, and dexamethasone) and imatinib mesylate followed by imatinib mesylate-based consolidation/maintenance therapy. Of these patients, 11 had de novo disease, 4 were primary failures after induction (without imatinib mesylate), and 5 were in complete remission (CR) after induction (without imatinib mesylate). All 15 patients treated for active disease achieved CR. Within a median of 3.5 months in first CR, 10 patients underwent allogeneic stem cell transplantation (SCT). One patient relapsed after matched related SCT. The other 9 patients remained alive in CR with median follow-up of 12 months after SCT (range, 1+ to 17+ months). Among 10 patients ineligible for (no donor or older age) or refusing allogeneic SCT, 1 patient relapsed after one year. There were 5 patients who remained alive in continuous CR for a median of 20 months (range, 4+ to 24+ months), with 2 older patients dying in CR at 15 and 16 months of comorbid conditions. Molecular CRs were achieved in both groups (SCT or no SCT). Outcome with hyper-CVAD and imatinib mesylate appears better than with prior regimens; continued accrual and longer follow-up of the current cohort is needed.

Adolescent↗

PubMed2003

Mylotarg, fludarabine, cytarabine (ara-C), and cyclosporine (MFAC) regimen as post-remission therapy in acute myelogenous leukemia.

PURPOSE: Mylotarg, a humanized anti-CD33 antibody linked to an antitumor antibiotic, is approved for the treatment of patients with relapsed acute myeloid leukemia (AML). Its role as a component of post-remission therapy in AML has not been established. The Mylotarg, fludarabine, cytarabine, and cyclosporine (MFAC) regimen was evaluated in patients in complete remission following Mylotarg-containing regimens. METHODS: The MFAC regimen comprised: Mylotarg 4.5 mg/m2 intravenously (i.v.) over 2 h after a loading dose of cyclosporine A (CSA) on day 1; fludarabine 15 mg/m2 i.v. over 30 min every 12 h for six doses on days 2 through 4; ara-C 0.5 g/m2 over 2 h every 12 h for six doses on days 2 through 4, 4 h after fludarabine started; CSA 6 mg/kg over 2 h, followed by 16 mg/kg continuous i.v. infusion on days 1 and 2. Patients in complete remission (CR) commenced idarubicin and ara-C (IA) alternating with MFAC or vice versa for 9 months from the date of CR. Idarubicin was administered at 8 mg/m2 on days 1 and 2 and ara-C at 1.5 g/m2 on days 1 and 2. RESULTS: A total of 22 patients received 76 courses of MFAC (35 courses) alternating with IA (41 courses) or vice versa. The interval between courses, and degrees of myelosuppression, were equivalent in the alternating regimens. Failure-free and 12-month survival rates of were 32% and 55%, respectively. Grade 3/4 toxicities, including sepsis, neutropenic fever, and nausea/vomiting, were equivalent with MFAC and IA. CONCLUSIONS: Post-remission therapy with MFAC is feasible and well tolerated in patients with AML.

Acute Disease↗

PubMed2003

Phase II study of alemtuzumab in chronic lymphoproliferative disorders.

BACKGROUND: Pilot studies showed that alemtuzumab is active in lymphoproliferative disorders. The authors conducted a Phase II trial to evaluate the efficacy and safety of alemtuzumab in advanced or refractory chronic lymphoproliferative disorders. METHODS: Seventy-eight patients were enrolled. The most common diagnoses were chronic lymphocytic leukemia (n = 42 patients) and T-cell prolymphocytic leukemia (n = 18 patients). Before entering the study, the patients had received multiple therapies (median, three therapies) and the median time from diagnosis was 7 years. Alemtuzumab was given intravenously at doses of 3 mg, 10 mg, and 30 mg on 3 consecutive days, after which 30 mg was administered 3 times a week. Patients were treated for 4-12 weeks depending on disease response. All patients received prophylactic trimethoprim/sulfamethoxazole and valacyclovir. RESULTS: The overall response rate was 35%, the complete response (CR) rate was 13%, and the partial response (PR) rate was 22%. The median duration of response was 18 months for patients achieving a CR and 7 months for patients achieving a PR. The median duration of survival was 25 months for patients who had a response and 12 months for the entire population. Normalization of the lymphocyte count was observed in 84% of patients and resolution of bone marrow involvement was observed in 49% of patients. The most common infusion-related adverse events were fever, rigors, skin rash, nausea, and dyspnea. These were most common during the first week of therapy. Hematologic toxicity was comprised of long-lasting lymphocytopenia and transient neutropenia and thrombocytopenia. Thirty-six patients (46%) experienced at least one episode of fever or infection. CONCLUSIONS: Alemtuzumab has a high response rate in patients with chronic lymphoproliferative disorders.

Adult↗

PubMed2003

Results of decitabine (5-aza-2'deoxycytidine) therapy in 130 patients with chronic myelogenous leukemia.

BACKGROUND: General and site-specific DNA methylation is associated with tumor progression and resistance in several cancers, including chronic myelogenous leukemia (CML). Decitabine is a hypomethylating agent that has shown encouraging preliminary anti-CML activity. This study evaluated the activity and toxicity of decitabine in different phases of CML. METHODS: One hundred and thirty patients with CML were treated: 123 with Philadelphia chromosome (Ph)-positive CML (64 blastic, 51 accelerated, 8 chronic) and 7 with Ph-negative CML. Decitabine was given at 100 mg/m(2) over 6 hours every 12 hours x 5 days (1000 mg/m(2) per course) in the first 13 patients, 75 mg/m(2) in the subsequent 33 patients, and 50 mg/m(2) in the remaining 84 patients. RESULTS: A total of 552 courses were given to the 130 patients. Only four patients (3%) died during the first course from myelosuppressive complications (three patients) or progressive disease (one patient). Of 64 patients in the CML blastic phase, 18 patients (28%) achieved objective responses. Of these 18 patients, 6 achieved complete hematologic responses (CHR), 2 achieved partial hematologic responses (PHR), 7 achieved hematologic improvements (HI), and 3 returned to the second chronic phase (second CP). Five patients (8%) had cytogenetic responses. Among 51 patients in the accelerated phase, 28 patients (55%) achieved objective responses (12 CHR, 10 PHR, 3 HI, and 3 second CP). Seven patients (14%) had cytogenetic responses. Among eight patients treated in the chronic phase, five (63%) had objective responses. Of seven patients treated for Ph-negative CML, four (57%) had objective responses. There was no evidence of a dose-response effect. The estimated 3-year survival rate was less than 5% in the blastic phase and 27% in the accelerated phase. The only significant toxicity reported was severe myelosuppression, which was delayed, prolonged, and dose dependent. With decitabine 50-75 mg/m(2), the median time to granulocyte recovery above 0.5 x 10(9)/L was about 4 weeks. Myelosuppression-associated complications included febrile episodes in 37% and documented infections in 34%. CONCLUSIONS: Decitabine appears to have significant anti-CML activity. Future studies should evaluate lower-dose, longer-exposure decitabine schedules alone in imatinib-resistant CML, as well as combinations of decitabine and imatinib in different CML phases.

Adolescent↗

PubMed2003

Rituximab in relapsed or refractory hairy cell leukemia.

The purpose of this study was to investigate the efficacy and safety of the monoclonal antibody, rituximab, in relapsed or refractory hairy cell leukemia (HCL). Fifteen patients with relapsed or primary refractory HCL after nucleoside analogs received rituximab 375 mg/m2 weekly for a total of 8 planned doses. An additional 4 doses could be administered to responders who had not achieved complete response (CR). The overall response rate was 80%. Eight patients (53%) achieved CR, 2 (13%) attained CR by hematologic parameters with residual marrow disease (1% to 5% marrow hairy cells), and 2 (13%) had a partial response. Of the 12 responders followed for a median of 32 months (range, 8 to 45+ months), 5 patients (42%) had progression of disease 8, 12, 18, 23, and 39 months from the start of therapy. Three patients failed to respond (after 4, 6, or 8 doses). Reductions in serum interleukin-2 receptor (sIL-2R) levels correlated with response. Toxicity was minimal, and no infectious episodes were observed. Rituximab has significant activity and minimal toxicity in HCL and warrants further study. Rituximab should be explored further in HCL with regard to eradication of minimal residual disease and in combination with nucleoside analogs.

Adult↗

PubMed2003

Treatment of Philadelphia chromosome-positive chronic myelogenous leukemia with weekly polyethylene glycol formulation of interferon-alpha-2b and low-dose cytosine arabinoside.

BACKGROUND: To evaluate the activity and toxicity of weekly Schering 54301, a polyethylene glycol formulation of interferon- alpha-2b (PEG-IFN-alpha-2b), with cytosine arabinoside (ara-C) in patients with chronic myelogenous leukemia (CML). METHODS: Seventy-six patients with Philadelphia chromosome (Ph)-positive early chronic-phase CML were treated with the combination of PEG-IFN-alpha-2b and ara-C (10 mg daily subcutaneously [s.c.]). The starting dose of PEG-IFN-alpha-2b was 6 microg/kg s.c. weekly in the first 24 patients but was reduced to 4.5 microg/kg in the next 52 patients. RESULTS: Overall, 73% of patients had a complete hematologic response, 35% of patients had a major cytogenetic response (Ph < 35%), and 21% of patients had a complete cytogenetic response (Ph = 0%). With a median follow-up of 19 months, the estimated 2-year survival rate was 89%. Therapy was discontinued in 24% of patients due to Grade III-IV toxicity. Frequent severe side effects that required dose reductions included neutropenia (49%), fatigue (43%), and neurologic toxicity (17%). The median PEG-IFN-alpha-2b and ara-C doses delivered were 3 microg/kg weekly and 7.5 mg daily, respectively, at 12 months of therapy. The activity and toxicity profiles of this combination was similar to those observed in historical patients treated with IFN-alpha and cytarabine. CONCLUSIONS: The combination of PEG-IFN-alpha-2b and ara-C is active but has significant toxicity in patients with chronic-phase CML at the dose schedule used. The recommended dose of PEG-IFN-alpha-2b in future combination studies is 3 microg/kg or less.

Adult↗

PubMed2003

Amifostine does not reduce the toxicity of the fludarabine and cyclophosphamide regimen in patients with chronic lymphocytic leukemia.

PURPOSE: Amifostine is an organic thiophosphate that may selectively protect normal tissues from the toxicities of chemotherapy. The combination of fludarabine and cyclophosphamide (FC) is highly active in patients with chronic lymphocytic leukemia (CLL). Infection is a serious toxicity of the FC regimen. METHODS: Amifostine was added to the FC regimen in a phase II study of 46 patients with CLL. Patients received FCA (fludarabine 30 mg/m(2) i.v. daily for 3 days, cyclophosphamide 300 mg/m(2) i.v. daily for 3 days, and amifostine 500 mg i.v. over 15 min daily for 3 days starting 30 min before cyclophosphamide) at intervals of 4-6 weeks for a maximum of six courses. RESULTS: Patients receiving FCA had equivalent rates of sepsis, early death, objective response and survival to those observed in a prior series of 78 patients treated with FC. Amifostine-associated toxicities included nausea, vomiting, and hypotension. CONCLUSION: The study amifostine regimen did not reduce the toxicity or activity of the FC regimen in patients with CLL.

Amifostine↗

PubMed2003

Anagrelide and imatinib mesylate combination therapy in patients with chronic myeloproliferative disorders.

PURPOSE: The tyrosine kinase inhibitor imatinib mesylate inhibits the function of the Bcr-Abl oncoprotein associated with Philadelphia-positive chronic myelogenous leukemia (CML). Anagrelide suppresses megakaryocyte proliferation and differentiation. The objectives of this study were to investigate the feasibility and safety of imatinib mesylate and anagrelide combination therapy in patients with Ph-positive CML or chronic myeloproliferative disorders (MPD) with persistent thrombocythemia. METHODS: This study was a retrospective review of all available records of patients with chronic MPD presenting to the M.D. Anderson Cancer Center between October 1998 and May 2002, treated with imatinib mesylate combined with anagrelide. RESULTS: Of 22 patients identified, 18 had Ph-positive CML (chronic phase, 16 patients; accelerated phase, 2 patients), 1 had agnogenic myeloid metaplasia (AMM), 2 had essential thrombocythemia (ET) and 1 had MPD transformed into refractory anemia with excess blasts (RAEB). The median age was 57 years (range 26-82 years). The median dose of imatinib mesylate administered was 400 mg (range 300-800 mg) and the median dose of anagrelide was 1.5 mg (range 0.5-4.0 mg). Imatinib mesylate and anagrelide combination therapy was feasible and tolerable. Of the 18 patients with Ph-positive CML, 15 in chronic phase and 1 in accelerated phase achieved a complete hematologic response (CHR), and 9 of the 18 achieved cytogenetic response (complete in 8 patients). No responses were noted in patients with AMM, ET or MPD transformed into RAEB. CONCLUSIONS: The combination of imatinib mesylate and anagrelide was safe and was associated with an 89% CHR rate in patients with CML in chronic phase and persistent thrombocythemia.

Adult↗

PubMed2003

Telomerase activity is prognostic in pediatric patients with acute myeloid leukemia: comparison with adult acute myeloid leukemia.

BACKGROUND: Significantly elevated telomerase activity (TA) has been found in samples from patients with almost all malignant hematologic diseases. The impact of elevated TA on the course of pediatric patients with acute myeloid leukemia (P-AML) is unknown. METHODS: Using a modified polymerase chain reaction-based, telomeric repeat-amplification protocol assay, the authors measured TA in bone marrow samples from 40 patients with P-AML and, for comparison, in 65 adult patients with AML (A-AML), excluding patients with French-American-British M3 disease. The results were correlated with patient characteristics and survival. RESULTS: TA in patients with P-AML was significantly lower compared with TA in patients with A-AML (P = 0.005). Patients who had P-AML with low TA had a projected 5-year survival rate of 88%, whereas patients who had P-AML with high TA had a projected 5-year survival rate of 43% (P = 0.009). Conversely, patients who had A-AML with very high TA (upper quartile) had significantly longer survival compared with patients who had A-AML with lower TA (P = 0.03). There was no correlation between complete remission rate or disease free survival and TA in P-AML or A-AML. In the A-AML group, when patients were separated by cytogenetic findings (poor prognosis vs. others), it was found that TA was significantly lower in patients with a poor prognosis, but the prognostic value of TA was not independent of cytogenetic status. CONCLUSIONS: The current results suggest, that for patients with P-AML, bone marrow TA is a highly significant prognostic factor.

Acute Disease↗