Acute promyelocytic leukemia after mitoxantrone therapy for multiple sclerosis

Mitoxantrone in relapsing-remitting and rapidly progressive multiple sclerosis: Ten-year clinical outcomes post-treatment with mitoxantrone

BACKGROUND

Mitoxantrone (MTX) has been used as an effective disease modifying treatment (DMT) in multiple sclerosis (MS). Evidence from studies demonstrates benefits of reduced relapse rates, MRI disease activity and disability progression in patients treated with MTX. While effective, MTX use has been limited due to potential adverse effects (AE) ranging from mild to potentially life-threatening AEs such as cardiotoxicity, bone marrow suppression and hematological malignancies. In this study we aimed to review the long-term clinical efficacy, tolerability, and AE profile of treatment with MTX in patients both with relapsing-remitting and rapidly progressive MS over a 10-year follow-up period.

METHODS

We collected prospective data of 70 patients with relapsing-remitting and rapidly progressive MS treated with MTX and followed-up over a 10-year period. Expanded disability status scale (EDSS) scores and annualized relapse rates (ARR) were assessed 1 year prior to MTX treatment, and at different time points (1, 2, 3, 5 and 10 years) during follow-up. We recorded the time to first relapse and 0.5-point EDSS increase to assess efficacy. We also obtained frequency data on AEs and patients withdrawn from treatment.

RESULTS

70 patients were started on treatment with MTX with 53 patients (34 relapsing-remitting MS, 19 progressive disease) completing the course. Mean EDSS progressed from 5.5 to 6.5 in the relapsing-remitting group and 6.7 to 9.0 in the progressive group over the study period. ARR in the RRMS group reduced at all time points from 2.2 prior to MTX to 0.3 by year 10. We reported 3 significant AEs, one chicken pox and subsequent acute promyelocytic leukemia, one left ventricular systolic dysfunction, one pancytopenia. The commonest AE reported was nausea/vomiting in 28 (40%) patients. Seventeen patients (5 relapsing-remitting, 12 progressive disease) stopped treatment. In fifteen (87%) of these this was due to lack of efficacy. In the remaining 2 patients, MTX was stopped due to one patient developing chicken pox and the other developing first-degree heart block.

CONCLUSION

Our study demonstrated that MTX is an effective disease modifying treatment for relapsing-remitting MS with a well-established risk profile. While MTX is now used less frequently, many MS and neurology services continue to follow-up patients who have been treated with MTX previously. Therefore, understanding the long-term effects risks and benefits remains relevant in this patient group. MTX is also a low-cost treatment in comparison to other high efficacy MS disease-modifying treatments and this may be beneficial in low resource settings.

Coupling the core of the anticancer drug etoposide to an oligonucleotide induces topoisomerase II-mediated cleavage at specific DNA sequences

Etoposide and other topoisomerase II-targeted drugs are important anticancer therapeutics. Unfortunately, the safe usage of these agents is limited by their indiscriminate induction of topoisomerase II-mediated DNA cleavage throughout the genome and by a lack of specificity toward cancer cells. Therefore, as a first step toward constraining the distribution of etoposide-induced DNA cleavage sites and developing sequence-specific topoisomerase II-targeted anticancer agents, we covalently coupled the core of etoposide to oligonucleotides centered on a topoisomerase II cleavage site in the PML gene. The initial sequence used for this ‘oligonucleotide-linked topoisomerase inhibitor’ (OTI) was identified as part of the translocation breakpoint of a patient with acute promyelocytic leukemia (APL). Subsequent OTI sequences were derived from the observed APL breakpoint between PML and RARA. Results indicate that OTIs can be used to direct the sites of etoposide-induced DNA cleavage mediated by topoisomerase IIα and topoisomerase IIβ. OTIs increased levels of enzyme-mediated cleavage by inhibiting DNA ligation, and cleavage complexes induced by OTIs were as stable as those induced by free etoposide. Finally, OTIs directed against the PML-RARA breakpoint displayed cleavage specificity for oligonucleotides with the translocation sequence over those with sequences matching either parental gene. These studies demonstrate the feasibility of using oligonucleotides to direct topoisomerase II-mediated DNA cleavage to specific sites in the genome.

Myeloid disorders after autoimmune disease

Autoimmune diseases (ADs) are associated with an increased risk not only of lymphoproliferative disorders but also of myeloid malignancies. The excess risk of myelodysplastic syndromes and/or acute myeloid leukemia is observed across several AD types, including systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disorders, multiple sclerosis, among others. The risk of developing myeloid neoplasms (MNs) is dependent on several variables, including the specific AD type, chronicity and severity of the AD, type and duration of exposure of disease modifying anti-rheumatic drugs or cytotoxics/immunosuppressives, and genetic predisposition risk. Putative triggering factors linking AD to elevated MN risk include AD-directed medications, shared genetic susceptibilities between the two disease entities, and chronic immune stimulation or bone marrow infiltration by the AD. Molecular mechanisms underpinning leukemogenesis remain largely speculative and warrant further investigation. Leukemias arising in patients with AD are not always 'therapy-related' in that MNs may develop in certain AD subtypes even among patients with no prior therapy exposure. Only a few studies have attempted to determine factors associated with MN development in AD but failed to demonstrate consistent characteristic clinical or paraclinical features. These reports have failed to demonstrate a clear correlation between individual agent exposure and subsequent leukemia development due to the low rates of therapy exposure compounded by the rarity of MN occurrence. Notwithstanding, the leukemogenic potential is best documented with agents such as azathioprine, cyclophosphamide, and mitoxantrone; this risk of MN development does not appear to be shared by biologic approaches such as anti-tumor necrosis factors-alpha inhibitors. In this article, we discuss plausible biologic mechanisms underlying MN pathogenesis in AD and review the data available on the development of MNs in patients with AD.

Patient preferences for attributes of multiple sclerosis disease-modifying therapies: development and results of a ratings-based conjoint analysis

BACKGROUND

Timely individualized treatment is essential to improving relapsing-remitting multiple sclerosis (RRMS) patient health outcomes, yet little is known about how patients make treatment decisions. We sought to evaluate RRMS patient preferences for risks and benefits of treatment.

METHODS

Fifty patients with RRMS completed conjoint analysis surveys with 16 hypothetical disease-modifying therapy (DMT) medication profiles developed using a fractional factorial design. Medication profiles were assigned preference ratings from 0 (not acceptable) to 10 (most favorable). Medication attributes included a range of benefits, adverse effects, administration routes, and market durations. Analytical models used linear mixed-effects regression.

RESULTS

Participants showed the highest preference for medication profiles that would improve their symptoms (β = 0.81-1.03, P < .001), not a proven DMT outcome. Preventing relapses, the main clinical trial outcome, was not associated with significant preferences (P = .35). Each year of preventing magnetic resonance imaging changes and disease symptom progression showed DMT preferences of 0.17 point (β = 0.17, P = .002) and 0.12 point (β = 0.12, P < .001), respectively. Daily oral administration was preferred over all parenteral routes (P < .001). A 1% increase in death or severe disability decreased relative DMT preference by 1.15 points (P < .001).

CONCLUSIONS

Patient preference focused on symptoms and prevention of progression but not on relapse prevention, the proven drug outcome. Patients were willing to accept some level of serious risk for certain types and amounts of benefits, and they strongly preferred daily oral administration over all other options.

Global characteristics of childhood acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) comprises approximately 5-10% of childhood acute myeloid leukemia (AML) cases in the US. While variation in this percentage among other populations was noted previously, global patterns of childhood APL have not been thoroughly characterized. In this comprehensive review of childhood APL, we examined its geographic pattern and the potential contribution of environmental factors to observed variation. In 142 studies (spanning >60 countries) identified, variation was apparent-de novo APL represented from 2% (Switzerland) to >50% (Nicaragua) of childhood AML in different geographic regions. Because a limited number of previous studies addressed specific environmental exposures that potentially underlie childhood APL development, we gathered 28 childhood cases of therapy-related APL, which exemplified associations between prior exposures to chemotherapeutic drugs/radiation and APL diagnosis. Future population-based studies examining childhood APL patterns and the potential association with specific environmental exposures and other risk factors are needed.

Patient centered decision making: use of conjoint analysis to determine risk-benefit trade-offs for preference sensitive treatment choices

Understanding patient preferences facilitates shared decision-making and focuses on patient-centered outcomes. Little is known about relapsing-remitting multiple sclerosis (RRMS) patient preferences for disease modifying therapies (DMTs). We use choice based conjoint (CBC) analysis to calculate patient preferences for risk/benefit trade-offs for hypothetical DMTs.

METHODS

Patients with RRMS were surveyed between 2012 and 2013. Our CBC survey mimicked the decision-making process and trade-offs of patients choosing DMTs, based on all possible DMT attributes. Mixed-effects logistic regression analyzed preferences. We estimated maximum acceptable risk trade-offs for various DMT benefits.

RESULTS

Severe side-effect risks had the biggest impact on patient preference with a 1% risk, decreasing patient preference five-fold compared to no risk. (OR=0.22, p<0.001). Symptom improvement was the most preferred benefit (OR=3.68, p<0.001), followed by prevention of progression of 10 years (OR=2.4, p<0.001). Daily oral administration had the third highest DMT preference rating (OR=2.08, p<0.001). Patients were willing to accept 0.08% severe risk for a year delayed relapse, and 0.22% for 4 vs 2 year prevented progression.

CONCLUSION

We provided patient preferences and risk-benefit trade-offs for attributes of all available DMTs. Evaluation of patient preferences is a key step in shared decision making and may significantly impact early drug initiation and compliance.

Prognostic factors for therapy-related acute myeloid leukaemia (t-AML)--a single centre experience

Prognostic parameters for treatment outcome in 42 consecutive patients with t-AML diagnosed and treated in a single centre between 2000-2010 (mean age: 56.07 years, range: 23-84; 30 females) were evaluated retrospectively/prospectively. Antecedent malignancy occurred in 37 patients (88.15%): 28 solid cancers (breast, n=14), nine haematological. History of previous chemotherapy (CT), radiotherapy (RT) alone and combined CT/RT was present in 42.9%, 6.19% and 30.1% patients, respectively. Primary disease was active in 11 patients (six relapsed or metastatic cancers; five autoimmune diseases). Myelodysplastic syndrome preceded t-AML in 29% of patients. Median latency period from prior CT/RT was 54.62 months (range: 6-243). Median WBC count was 27.23 × 10⁹/L, platelet count 62.29 × 10⁹/L, haemoglobin level 87.83 g/L, peripheral blood and bone marrow blast percentage 30.7% and 66.7% respectively, serum LDH 1216 U/L. Aberrant expression of B or T lymphoid markers was registered in seven out of 39 and six out of 39 patients, respectively. Aberrant karyotype was detected in 24 out of 33 (72.7%) of eligible patients: favourable: 15.2%, intermediate: 42.4% and unfavourable: 42.4%. Eastern Cooperative Oncology Group (ECOG) performance status greater or equal to 2 and Haematopoietic Cell Transplantation Specific Comorbidity Index (HCT-CI) greater or equal to 3 exhibited 83.3% and 76.2% patients, respectively. Intensive induction CT for t-AML was administered in 24 patients. The median follow-up and the median overall survival (OS) for the whole cohort were 2 months and 5.94 months (range: 0.5-34), respectively. In 10 patients (23.8%) achieving complete remission (CR), median disease free survival (DFS) was 11.8 months (range: 4-32). Only CD19 expression, pretreatment karyotype, ECOG PS, HCT-CI and activity of primary disease had impact on OS (P<0.05).

Long-term safety profile of mitoxantrone in a French cohort of 802 multiple sclerosis patients: a 5-year prospective study

Background: From 2001, a French multicentre study was conducted prospectively in a large cohort of MS patients and annually updated up to at least 5 years after initiation of MITOX therapy. Objective: To determine long-term safety profile of mitoxantrone (MITOX) in multiple sclerosis (MS).

Methods: Eight hundred and two patients from 12 MS centres (308 relapsing–remitting, 352 secondary progressive and 142 primary progressive) received MITOX monthly for 6 months (87%) or every 3 months (13%). Patients underwent clinical and haematologic evaluations before every MITOX infusion and every 6–12 months up to 5 years after MITOX start. Echocardiograms were performed at the start and end of MITOX and up to 5 years after.

Results: The cohort was followed for 5354 patient-years (mean). One out of 802 patients (0.1%) presented with acute congestive heart failure and 39 out of 794 patients (4.9%) presented with asymptomatic left ventricular ejection fraction reduction under 50% (persistent in 11 patients (28%), transient in 27 patients (69%), on the last scan at year 5 in 1 patient). Two cases of therapy-related leukaemia (0.25%) were detected 20 months after MITOX start (one death and one with 8 years confirmed remission). Of the 317 women treated before the age of 45, 17.3% developed a persistent age-dependant amenorrhea. Conclusion: This large cohort with at least 5 years of follow-up provided good insights into the long-term safety profile of MITOX in MS.

Revision of the risk of secondary leukaemia after mitoxantrone in multiple sclerosis populations is required

The objective in this paper is to compare the cumulative incidence and incidence density of therapy-related acute myeloid leukaemia in two cohorts of patients with multiple sclerosis treated with mitoxantrone, and with previously reported data in the literature. Six new cases of acute myeloid leukaemia were observed by prospectively following two Spanish series of 142 and 88 patients with worsening relapsing multiple sclerosis and secondary-progressive disease treated with mitoxantrone. A literature review shows 32 further cases of acute myeloid leukaemia reported, 65.6% of which are therapy-related acute promyelocytic leukaemia. Five cases in the cohorts fulfilled the diagnostic criteria for acute promyelocytic leukaemia, and one patient was diagnosed with pre-B-acute lymphoblastic leukaemia. Acute myeloid leukaemia latency after mitoxantrone discontinuation was 1 to 45 months. The accumulated incidence and incidence density was 2.82% and 0.62%, respectively, in the Valencian cohort, and 2.27% and 0.44% in the Catalonian cohort. In the only seven previously reported series, the accumulated incidence varied from 0.15% to 0.80%. The real incidence of acute myeloid leukaemia after mitoxantrone therapy in the multiple sclerosis population could be higher as evidenced by the growing number of cases reported. Haematological monitoring should continue for at least 5 years after the last dose of mitoxantrone. These data stress the necessity of re-evaluating this risk.

Multiple sclerosis

Multiple sclerosis is the most common disabling neurologic disease affecting young adults and adolescents in the United States. The first objective of this article is to familiarize nonspecialists with the cardinal features of multiple sclerosis and our current understanding of its etiology, epidemiology, and natural history. The second objective is to explain the approach to diagnosis. The third is to clarify current evidence-based treatment strategies and their roles in disease modification. The overall goal is to facilitate the timely evaluation and confirmation of diagnosis and enhance effective management through collaboration among primary physicians, neurologists, and other care providers who are confronted with these formidably challenging patients.

Molecular analysis of t(15;17) genomic breakpoints in secondary acute promyelocytic leukemia arising after treatment of multiple sclerosis

Therapy-related acute promyelocytic leukemia (t-APL) with t(15;17) translocation is a well-recognized complication of cancer treatment with agents targeting topoisomerase II. However, cases are emerging after mitoxantrone therapy for multiple sclerosis (MS). Analysis of 12 cases of mitoxantrone-related t-APL in MS patients revealed an altered distribution of chromosome 15 breakpoints versus de novo APL, biased toward disruption within PML intron 6 (11 of 12, 92% vs 622 of 1022, 61%: P = .035). Despite this intron spanning approximately 1 kb, breakpoints in 5 mitoxantrone-treated patients fell within an 8-bp region (1482-9) corresponding to the "hotspot" previously reported in t-APL, complicating mitoxantrone-containing breast cancer therapy. Another shared breakpoint was identified within the approximately 17-kb RARA intron 2 involving 2 t-APL cases arising after mitoxantrone treatment for MS and breast cancer, respectively. Analysis of PML and RARA genomic breakpoints in functional assays in 4 cases, including the shared RARA intron 2 breakpoint at 14 446-49, confirmed each to be preferential sites of topoisomerase IIalpha-mediated DNA cleavage in the presence of mitoxantrone. This study further supports the presence of preferential sites of DNA damage induced by mitoxantrone in PML and RARA genes that may underlie the propensity to develop this subtype of leukemia after exposure to this agent.