Prognostic significance of serum ferritin level at diagnosis in myelodysplastic syndrome

The Role of Hepcidin in Myelodysplastic Syndromes (MDS): A Systematic Review of Observational Studies

Iron overload emerges as a serious complication in myelodysplastic syndromes (MDS), particularly associated with frequent transfusions during the course of the disease. The discovery and description of hepcidin's mechanisms of action have contributed to a deeper understanding of iron metabolism. The existing literature reports a potential role of hepcidin in MDS, yet these data are fragmented and presented in an unstructured, somewhat chaotic manner. Hence, to address the existing data, we performed a systematic review of observational studies examining hepcidin levels in MDS. An extensive review of three bibliographic databases (Pubmed, Web of Science, and Scopus) enabled us to identify 12 observational studies. These studies focused primarily on adult patients with low-risk MDS who underwent transfusions and chelation therapy. An in-depth analysis of these manuscripts led to four main conclusions: (1) although high serum hepcidin levels are associated with MDS, most studies generally have not found a significant difference in these levels between patients and healthy individuals; (2) serum hepcidin levels are specific to MDS type; (3) serum hepcidin levels in MDS are strongly associated with transfusions and the genetic status of patients; and (4) high-risk MDS is associated with high serum hepcidin levels. While we have furnished a comprehensive summary of the significance of hepcidin in MDS, there are still gaps that future research should address. This pertains primarily to the capacity of hepcidin in predicting adverse outcomes for MDS patients and evaluating the efficacy of chelation therapy or the need for transfusion.

Serum Erythropoietin level in anemia of elderly with unclear etiology

Anemia is a common condition, but its causes are often unclear, especially in elderly adults. Erythropoietin (EPO) levels are known to be elevated in myelodysplastic syndrome and hematologic malignancies, but decreased in chronic benign anemia. This study aimed to investigate whether EPO levels could be used to identify underlying bone marrow diseases including malignancies, among elderly anemic patients with unclear etiology. This single centered retrospective study included patients presented with isolated anemia and had their EPO levels measured at their first visit. Patients were divided into two groups: bone marrow disease and benign etiologic anemia, based on observation and bone marrow test results. Out of 1180 patients reviewed, 81 patients with anemia of unclear etiology were identified, including 67 with benign anemia and 14 with bone marrow disease. Statistically significant difference in EPO levels between these two groups (P < 0.001) were observed. The receiver operating characteristic curve analysis showed that an EPO cut-off value of 36.4 mU/mL had a sensitivity and specificity of 92.8% and 94.0% for detecting underlying bone marrow disease, respectively. We suggest measuring serum EPO levels can aid in the early detection of benign anemia from bone marrow disease, including malignancies, with high sensitivity and specificity.

Does ferritin level affect the outcomes of autologous stem cell transplantation equally in all diseases?

BACKGROUND

In this retrospective study, we evaluated the effect of ferritin levels on the outcomes of autologous stem cell transplantation in patients with MM or lymphoma.

METHODS

In this study, 170 patients with measured ferritin levels within one month before transplantation who underwent ASCT with the diagnosis of MM or lymphoma were evaluated. The cut-off value of ferritin was determined as 500 ng/mL to evaluate the transplant outcomes in both groups. The hematological recovery status/duration, febrile neutropenia rate, hospitalization time, transplant-related mortality (TRM) in the first 100 days, and OS were evaluated according to the ferritin level RESULTS: Of all patients, 105 (61,8%) were diagnosed with MM and 65 (38.2%) with lymphoma. Ferritin levels had no statistically significant effect on the engraftment status/times, the febrile neutropenia rates, and hospitalization times of both lymphoma and myeloma patients (p > .05). Ferritin level was not significantly associated with TRM in MM (p = .224). However, in lymphoma, ferritin level was significantly associated with TRM (33.3% for ferritin level ≥500 ng/L vs. 5.3% for ferritin level ng/mL, p = .005). There was no statistically significant correlation between ferritin value and OS in MM group [ferritin level ≥ 500 ng/L: 39.9 months (95% CI: 33.7-46.1) and ferritin level 500 ng/mL: 39.4 months (95% CI: 36.5-42.2), p = .446]. Ferritin level was significantly associated with OS in patients with lymphoma [ferritin level ≥ 500 ng/L: 22.1 months 95% CI: 14.7-29.5), ferritin level 500 ng/mL: 27.3 months (95% CI: 22.4-32.2), p = .038] CONCLUSION: High ferritin level is important prognostic factor on survival after ASCT in patients with lymphoma.

A Systematic Literature Review of the Relationship between Serum Ferritin and Outcomes in Myelodysplastic Syndromes

Anemia is the most common form of cytopenia in patients with myelodysplastic syndromes (MDS), who require chronic red blood cell transfusions and may present high serum ferritin (SF) levels as a result of iron overload. To better understand the potential effects of high SF levels, we conducted a systematic literature review (SLR) to identify evidence on the relationship between SF levels and clinical, economic, or humanistic outcomes in adult patients with MDS. Of 267 references identified, 21 were included. No studies assessing SF levels and their relationship with humanistic or economic outcomes were identified. Increased SF levels were an indicator of worse overall survival and other worsened outcomes; however, the association was not consistently significant. SF levels were a significant prognostic factor for relapse incidence of MDS and showed a significant positive correlation with number of blood units transfused but were not associated with progression to acute myeloid leukemia or the time to transformation. Higher SF levels were also an indicator of a lower likelihood of leukemia-free survival, relapse-free survival, and event-free survival. The SLR suggests that SF levels are associated with clinical outcomes in MDS, with higher levels correlated with number of blood units transfused, frequently indicating worse outcomes.

Rare Case of Multiple Lineage Dysplasia Myelodysplastic Syndrome Presenting with Only Anemia: A Case Report

BACKGROUND: Myelodysplastic syndrome (MDS) is a heterogeneous group of hematopoietic stem cell disorders which is characterized by ineffective hematopoiesis and risk of progression into acute myeloid leukemia. The diagnosis and classification of MDS are determined from the findings of dysplasia in one or more cell lineage and the percentage of blast cell on bone marrow examination. However, it should be noted that an abnormality in one marrow cell lineage does not necessarily translate to the corresponding clinical phenotype. Here, we present a case of MDS with multilineage dysplasia (MLD) (erythrocyte, leukocyte, and thrombocyte) from bone marrow aspiration, but with anemia as the sole clinical manifestation (single cytopenia). CASE REPORT: A 78-year-old male patient came to our clinic on July 10, 2020, with chief complaint of worsening fatigue which started approximately 1 year before visit. His vital signs during the visit were stable and no other abnormalities observed other than pale conjunctivae. Complete blood count showed macrocytic anemia with no abnormalities in leukocyte count and thrombocyte count, which suggested a single cytopenia. Peripheral blood smear was negative for megaloblasts and hypersegmented neutrophils. The patient’s bone marrow examination showed MDS with MLD. This result was in contrast to complete blood count examination which only showed anemia (single cytopenia). CONCLUSION: This case showed that there could be discrepancy between clinical manifestations of the cytopenia with bone marrow dysplasia, which highlighted the importance of conducting bone marrow examination to properly classify MDS type.

Predicting outcome in higher-risk myelodysplastic syndrome patients treated with azacitidine

5-Azacitidine (5-AZA) is widely used for the treatment of higher-risk myelodysplastic syndromes. However, response and survival rates vary considerably, while indicated treatment duration remains undefined. For these reasons, factors determining response and survival are of major importance. Clinical, morphological, flow cytometry, cytogenetic and molecular factors are discussed in this review. Biomarkers predictive of response and prognosis, as well as their link to the mode of action of 5-AZA are also addressed, shifting the focus from clinical practice to investigational research. Their use could further improve prognostic classification of 5-AZA treated higher-risk myelodysplastic syndromes in the near future.

Serum ferritin and ECOG performance status predict the response and improve the prognostic value of IPSS or IPSS-R in patients with high-risk myelodysplastic syndromes and oligoblastic acute myeloid leukemia treated with 5-azacytidine: a retrospective analysis of the Hellenic national registry of myelodysplastic and hypoplastic syndromes

Background:

5-azacytidine (5-AZA) improves survival of patients with higher-risk myelodysplastic syndromes (MDSs) and oligoblastic acute myeloid leukemia (AML); however, predictive factors for response and outcome have not been consistently studied.

Methods:

This study of the Hellenic MDS Study Group included 687 consecutive patients with higher-risk MDS and oligoblastic AML treated with 5-AZA.

Results:

The International Prognostic Scoring System (IPSS) revised version (IPSS-R), Eastern Cooperative Oncology Group Performance Status (ECOG PS) (0 or 1 versus ⩾2) and baseline serum ferritin (SF) levels > 520 ng/ml were shown to independently predict response to 5-AZA. In the survival analysis, the IPSS and IPSS-R risk classification systems along with the ECOG PS and SF levels > 520 ng/ml proved to be independent prognosticators for overall survival (OS), as well as for leukemia-free survival (LFS). Next, we built new multivariate models for OS and LFS, incorporating only ECOG PS and SF levels besides IPSS or IPSS-R risk classification systems. Thereby, the new modified IPSS and IPSS-R risk classification systems (H-PSS, H-PSS-R) could each discriminate a low, an intermediate and a high-risk patient group regarding OS and LFS. The H-PSS and H-PSS-R proved to be better predictors of OS than their previous counterparts as well as the French prognostic score, while the most powerful OS predictor was the new, H-PSS-R system.

Conclusions:

ECOG PS and SF levels > 520 ng/ml independently predict response to 5-AZA, OS and LFS. Their incorporation in the IPSS and IPSS-R scores enhances these scores’ predictive power in 5-AZA-treated higher-risk MDS and oligoblastic AML patients.

Clinical outcome of older adults with acute myeloid Leukemia: An analysis of a large tertiary referral Center over two decades

OBJECTIVE

In older adults with acute myeloid leukemia (AML), the overall outcome is still dismal and long-term data on survival are scarce, particularly outside of clinical trials. Here, we assess characteristics, prognostic factors and long-term survival in patients ≥60 years who were treated for AML at our center over the past 17 years.

METHODS

590 older adults with newly diagnosed AML were characterized according to Eastern Cooperative Oncology Group (ECOG) score, Charlson comorbidity index (CCI), European LeukemiaNet (ELN) risk, type of therapy, serum ferritin (SF) and further baseline characteristics. Survival analysis was performed accordingly.

RESULTS

Median age was 68 years and most patients were in good general condition. Median follow-up was 55.8 months. Of all patients, 66% received intensive chemotherapy (IC) +/- allogeneic hematopoietic stem cell transplantation (allo-HSCT). The remaining cohort received palliative chemotherapy (PC, 26%) or best supportive care only (BSC, 8%). Enrollment rate for interventional clinical trials was 26%. 5-year overall survival (OS) and relapse-free survival (RFS) were 18% (median 12.5 months) and 11,5% (median 10.0 months). Long-term survival was independently influenced by ECOG score, ELN risk group, baseline SF, previous myocardial infarction, and choice of therapy, but not consistently by age or CCI. Considering therapeutic subgroups, the contribution of particular parameters in predicting OS was most compelling in IC patients, but less consistent with PC or BSC.

CONCLUSION

Our results provide thorough insights into prognostication within therapeutic subgroups and emphasize the need for more detailed prognostic algorithms and routine geriatric assessment in the treatment of older adults with AML.

The Effects of Human BDH2 on the Cell Cycle, Differentiation, and Apoptosis and Associations with Leukemia Transformation in Myelodysplastic Syndrome

Iron overload is related to leukemia transformation in myelodysplastic syndrome (MDS) patients. Siderophores help to transport iron. Type 2-hydroxybutyrate dehydrogenase (BDH2) is a rate-limiting factor in the biogenesis of siderophores. Using qRT-PCR, we analyze BDH2mRNA expression in the bone marrow (BM) of 187 MDS patients, 119 de novo acute myeloid leukemia (AML) patients, and 43 lymphoma patients with normal BM. Elevated BDH2mRNA expression in BM is observed in MDS patients (n = 187 vs. 43, normal BM; P = 0.009), and this is related to ferritin levels. Patients with higher BDH2 expression show a greater risk of leukemia progression (15.25% vs. 3.77%, lower expression; P = 0.017) and shorter leukemia-free-survival (medium LFS, 9 years vs. 7 years; P = 0.024), as do patients with a ferritin level ≥350 ng/mL. Additionally, we investigate the mechanisms related to the prognostic ability of BDH2 by using BDH2-KD THP1. The cell cycle analysis, surface markers, and special stain studies indicate that BDH2-KD induces differentiation and decreases the growth rate of THP1 cells, which is associated with the retardation of the cell cycle. Moreover, many genes, including genes related to mitochondrial catabolism, oncogenes, tumor suppressor genes, and genes related to cell differentiation and proliferation influence BDH2-KD THP1 cells. Herein, we demonstrate that BDH2 is involved in cell cycle arrest and the inhibition of differentiation in malignant cells. Furthermore, the high BDH2 expression in MDS patients could be suggestive of a poor prognostic factor. This study provides a foundation for further research on the roles of BDH2 and iron metabolism in the pathogenesis of MDS.

The impact of iron chelation therapy on patients with lower/intermediate IPSS MDS and the prognostic role of elevated serum ferritin in patients with MDS and AML: A meta-analysis

Serum ferritin (SF) has been identified as a potential prognostic factor for patients undergoing stem cell transplantation, but the prognostic value of SF in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) patients and the impact of iron chelation therapy (ICT) on MDS patients are controversial. The present meta-analysis aimed to better elucidate these relationships.Three electronic databases were searched systematically to identify reports on the prognostic role of SF in MDS and AML patients, and those investigating the impact of ICT on prognosis of MDS patients. The hazard ratios (HRs) and its 95% confidence interval (95%CI) were extracted from the identified studies using Cox proportional hazard regression model for overall survival (OS) and progression of MDS to AML.Twenty reports including 1066 AML patients and 4054 MDS patients were included in present study. The overall pooled HRs for OS of AML and MDS patients with elevated SF prior to transplantation was 1.73 (1.40-2.14), subgroup analyses stratified by the cut-off value of SF ≥1400/1000 ng/mL showed that the pooled HRs were 1.45 (0.98-2.15) and 1.65 (1.30-2.10), respectively. The pooled HRs for ICT in MDS patients was 0.30 (0.23-0.40). For ICT, the pooled HRs for the progression of MDS to AML was 0.84 (0.61-1.61).SF has a negative impact on the OS of AML and MDS patients when it is higher than 1000 ng/mL. ICT can improve the OS of MDS patients with iron overload but it is not associated with the progression of MDS to AML.

In myelodysplastic syndrome cases, what should be the level of ferritin which has prognostic value?

OBJECTIVES

Myelodysplastic syndrome (MDS) is a highly mortal disease in which anemia is unresponsive to treatment. In this study, the effect of basal ferritin values on prognosis and survival was investigated in MDS patients without history of transfusion.

METHODS

Data were retrospectively analyzed for 62 MDS cases. The cases were divided into two groups according to ferritin values.

RESULTS

The mean survival time was 61.1±4.8 months. During the follow-up period, 34 (54.8%) patients deceased. Median ferritin level was 358ng/mL. The serum ferritin (SF) level associated with mortality was determined as 400ng/mL (ROC area for SF was 0.731 with a cutoff value of 400; sensitivity and specificity were 70.7% and 68.2%, respectively) (P=0.002). There were 29 (46.8%) patients with serum ferritin levels of ≥400ng/mL. Patients with serum ferritin levels≥400ng/mL had low survival rates. Ferritin≥400ng/mL was associated with six times increased mortality (P=0.001).

CONCLUSION

Although the acceptable ferritin level at the start of chelation therapy is 1000ng/mL, the fact that 400ng/mL value is associated with survival in our study suggests that it may be useful to start chelation therapy in the early period. Further case studies on the subject are required.

Prognostic Value of Ferritin-to-Hemoglobin Ratio in Patients with Advanced Non-Small-Cell Lung Cancer

Background: Among commonly used biomarkers that reflect overall health in patients with cancer, hemoglobin is an iron-containing, oxygen-carrying protein in red blood cells, and serum ferritin is an iron-storage protein. This study investigated the ability of the ferritin-to-hemoglobin ratio to predict survival in patients with advanced non-small-cell lung cancer (NSCLC).

Methods: The medical records of patients with pathologically confirmed advanced NSCLC were retrospectively reviewed. The ferritin level, hemoglobin level, and ferritin-to-hemoglobin ratio at the initiation of treatment were investigated. After descriptive analysis of the ferritin-to-hemoglobin ratio, the optimal diagnostic cutoff value for survival was determined using receiver operating characteristic analysis. After dichotomizing patients according to the optimal cutoff value, the prognostic effect of the ferritin-to-hemoglobin ratio was assessed. Overall survival (OS) was calculated using Kaplan-Meier analysis and compared using log-rank tests. Cox proportional hazards regression was used to evaluate the prognostic effect with respect to survival.

Results: Of the enrolled patients, 91.3% had stage IV NSCLC, 42.0% had an Eastern Cooperative Oncology Group-performance status (ECOG-PS) score of 2, and 56.5% previously underwent systemic chemotherapy. The median OS of enrolled patients was 11.5 months. The range of the ferritin-to-hemoglobin ratio was 0.6-294.2, and the optimal cutoff value of the ferritin-to-hemoglobin ratio for survival was 13.0 (sensitivity, 58.5%; specificity, 80.0%; area under the curve = 0.68; P = 0.004). The median OS of patients with a low ferritin-to-hemoglobin ratio (<13.0) was 19.7 months, whereas that of patients with a high ferritin-to-hemoglobin ratio (≥13.0) was 8.5 months (P < 0.001). After eliminating confounding factors such as age, sex, ECOG-PS, histologic type, and C-reactive protein level, a high ferritin-to-hemoglobin ratio was significantly associated with poor survival. The multivariate proportional hazards model revealed that the ferritin-to-hemoglobin ratio was an independent prognostic marker for survival (hazard ratio, 1.91; 95% confidence interval, 1.27-2.88; P = 0.002).

Conclusion: The ferritin-to-hemoglobin ratio, a potential parameter of tumor progression, was a significant prognostic factor for OS, with a direct correlation to survival time in patients with advanced NSCLC.

Chronic myelomonocytic leukemia treated with 5-azacytidine - results from the Hellenic 5-Azacytidine Registry: proposal of a new risk stratification system

Hypomethylating agents are widely used in chronic myelomonocytic leukemia (CMML). We analyzed the characteristics of 88 patients with CMML homogeneously treated with 5-azacytidine (Hellenic 5-Azacytidine Registry). The overall response rate was 48.9% and the median overall survival (OS) 29.7 months. Out of the seven most widely used prognostic scoring systems for CMML, the Dusseldorf score (DUSS) showed the best prognostic capability (HR, 2.27; p < .001). Forty-one (48.8%) patients progressed to acute myeloid leukemia (AML) after a median time of 15.2 months following treatment initiation. High serum ferritin levels at diagnosis were independently correlated with low OS (HR, 2.84; p = .022), as were circulating blasts (HR, 3.47; p = .014), while a platelet count <100 × 10⁹/L was marginally predictive of lower OS (HR, 1.45; p = .06). We selected these three factors to create a new risk stratification system for CMML with three risk groups. Finally, we highlighted for the first time the prognostic significance of serum ferritin levels in CMML.

AML: high serum ferritin at initial diagnosis has a negative impact on long-term survival

Increased serum ferritin (SF) is common in hematologic malignancies; however, its prognostic role in acute myeloid leukemia (AML) is not clearly established. We examined the impact of baseline SF on long-term survival in 137 intensively treated AML patients. Patients and baseline characteristics were retrieved from an AML database at Charité University Medical Center Berlin, Campus Virchow Clinic. After c-reactive protein (CRP)-based adjustment for inflammation, patients were grouped according to their baseline SF level. Survival analysis was performed accordingly. A significant decline in overall survival and relapse-free survival was observed in patients with high SF as compared to those with low SF. Furthermore, elevated baseline SF remained an independent poor prognostic factor within the multivariate analysis and was associated with a significant higher risk of relapse and non-relapse mortality (NRM). In conclusion, our data show that elevated baseline SF has a negative impact on long-term survival in intensively treated AML patients.

Effect of the Ginger Derivative, 6-Shogaol, on Ferritin Levels in Patients With Low to Intermediate-1-Risk Myelodysplastic Syndrome-A Small, Investigative Study

Background:

Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal stem cell disorders characterized by dysplastic and ineffective hematopoiesis and peripheral cytopenias. Elevated serum ferritin (SF) is often observed in nontransfused, lower risk MDS. It has been reported that ineffective erythropoiesis enhances iron absorption in MDS through downregulation of hepcidin and its prohormones such that SF rises.

Aim:

To determine the effect of 6-shogaol, a dehydration derivative of ginger, known to have hepatoprotective and chemotherapeutic activity, on 6 early-stage, transfusion-independent patients with MDS, 3 of whom had raised levels of SF.

Method:

Six patients with MDS with low or intermediate-1 subtypes, as defined by the International Prognostic Scoring System (IPSS), were recruited into the study and were administered 1 gel capsule daily containing 20 mg ginger extract standardized for 20% 6-shogaol. Blood and urine samples were collected and various markers monitored at regular intervals.

Results:

6-shogaol caused a decrease in SF levels in 3 of 6 patients with early MDS (50%) whose SF levels were elevated at the start of the study. Our findings suggest upregulation of hepcidin and its prohormones, possibly through an improvement in liver function.

Discussion:

In light of the encouraging results in this small, investigative study, we are planning a larger study to confirm the beneficial effect of 6-shogaol in patients with raised ferritin levels due to ineffective erythropoiesis.

Role of serum ferritin level on overall survival in patients with myelodysplastic syndromes: Results of a meta-analysis of observational studies

BACKGROUND

The role of serum ferritin (SF) as a prognostic factor has been analyzed in patients with myelodysplastic syndromes (MDS) who have undergone hematopoietic stem cell transplantation (HSCT), but the prognostic role of elevated SF levels is still controversial in lower risk MDS patients. Therefore, we performed a meta-analysis of all available published literature to evaluate whether elevated SF levels are associated with a worse overall survival (OS) among patients with low risk MDS.

MATERIAL AND METHODS

A systematic bibliographic search of relevant studies was undertaken in accordance with guidelines for meta-analysis of observational studies in epidemiology. Electronic databases were searched through July 2016 for studies examining the level of SF as a prognostic factor in the adults affected by MDS.

RESULTS

Six articles were included in the meta-analysis. A significant association between OS and SF was achieved for the threshold of SF≥1000 ng/mL, when the only study that used SF cut-off ≥2000 ng/mL was not included in the meta-analysis (RR = 1.33; 95% CI = 1.06-1.67). The estimated risk was 2.58 (95% CI = 1.41-4.74) when a SF cut-off≥500 ng/mL was considered.

CONCLUSIONS

Our findings underlined a worse survival in patients with MDS who had higher SF levels. The association was stronger and achieved statistical significance after stratification of analyses in which we excluded cut-offs of SF level considered as outliers. These results suggest that negative impact on OS already exist at SF level ≥500 ng/mL. Prospective studies, are needed to better understand this relationship and, above all, to clarify whether earlier iron chelation therapy could improve patients' OS.

Decitabine as a First-Line Treatment for Older Adults Newly Diagnosed with Acute Myeloid Leukemia

PURPOSE

Decitabine, a DNA hypomethylating agent, was recently approved for use in Korea for older adults with acute myeloid leukemia (AML) who are not candidates for standard chemotherapy. This study aimed to evaluate the role of decitabine as a first-line treatment for older adults with AML.

MATERIALS AND METHODS

Twenty-four patients with AML who received at least one course of decitabine (20 mg/m²/d intravenously for 5 days every 4 weeks) as a first-line therapy at Severance Hospital were evaluated retrospectively.

RESULTS

The median age of the patients was 73.5 years. The longest follow-up duration was 502 days. A total of 113 cycles of treatment were given to 24 patients, and the median number of cycles was four (range, 1-14). Thirteen patients dropped out because of death, no or loss of response, patient refusal, or transfer to another hospital. Twenty-one (87.5%) and 12 (50%) patients completed the second and fourth cycles, respectively, and responses to treatment were evaluated in 17. A complete response (CR) or CR with incomplete blood-count recovery was achieved in six (35.3%) patients, and the estimated median overall survival was 502 days. Ten patients developed grade >2 hematologic or non-hematologic toxicities. In univariate analysis, bone marrow blasts, lactate dehydrogenase, serum ferritin level, and bone marrow iron were significantly associated with response to decitabine.

CONCLUSION

Five-day decitabine treatment showed acceptable efficacy in older patients with AML who are unfit for conventional chemotherapy, with a CR rate 35.3% and about a median overall survival of 18 months.

Methodological problems with population cancer studies: The forgotten confounding factors

Among clinical physicians it is the population study that is considered to be the “gold standard” of medical evidence concerning acceptable treatments. As new information comes to light concerning the many variables and confounding factors that can affect such studies, many older studies lose much of their original impact. While newer population studies take into consideration a far greater number of confounding factors many are still omitted and a number of these omitted factors can have profound effects on interpretation and validity of the study. In this editorial, I will discuss some of the omitted confounding factors and demonstrate how they can alter the interpretation of these papers and their clinical application.

Oxidative stress levels are correlated with P15 and P16 gene promoter methylation in myelodysplastic syndrome patients

Oxidative stress and abnormal DNA methylation have been implicated in some types of cancer, namely in myelodysplastic syndromes (MDS). Since both mechanisms are observed in MDS patients, we analyzed the correlation of intracellular levels of peroxides, superoxide anion, and glutathione (GSH), as well as ratios of peroxides/GSH and superoxide/GSH, with the methylation status of P15 and P16 gene promoters in bone marrow leukocytes from MDS patients. Compared to controls, these patients had lower GSH content, higher peroxide levels, peroxides/GSH and superoxide/GSH ratios, as well as higher methylation frequency of P15 and P16 gene promoters. Moreover, patients with methylated P15 gene had higher oxidative stress levels than patients without methylation (peroxides: 460 ± 42 MIF vs 229 ± 25 MIF, p = 0.001; superoxide: 383 ± 48 MIF vs 243 ± 17 MIF, p = 0.022; peroxides/GSH: 2.50 ± 0.08 vs 1.04 ± 0.34, p < 0.001; superoxide/GSH: 1.76 ± 0.21 vs 1.31 ± 0.10, p = 0.007). Patients with methylated P16 and at least one methylated gene had higher peroxide levels as well as peroxides/GSH ratio than patients without methylation. Interestingly, oxidative stress levels allow the discrimination of patients without methylation from ones with methylated P15, methylated P16, or at least one methylated (P15 or P16) promoter. Taken together, these findings support the hypothesis that oxidative stress is correlated with P15 and P16 hypermethylation.

Elevated total iron-binding capacity as a predictor of response to deferasirox therapy in the setting of chronic iron overload

It is difficult to predict the efficacy of deferasirox (DFX) as its pharmacokinetics varies among patients. The area under the curve (AUC) is reportedly useful for determining adequate DFX dosage; however, serum concentration measurements are often challenging. Effective DFX dosage is thus defined by assessing the efficacy of this agent in clinical practice. To analyze a predictive response marker to DFX therapy for use in adjusting the effective dosage during the early treatment phase, we retrospectively evaluated 39 DFX-treated patients. We defined response as a >40 % decrease in serum ferritin concentration from the pretreatment level. A maximum elevation of the total iron-binding capacity (TIBC) correlated with response in a multivariate analysis of iron metabolic markers (R (2) = 0.37, p < 0.001). A receiver operating characteristic curve analysis revealed that TIBC elevation had an AUC of 0.85 (p < 0.001) and the optimal cut-off value of TIBC elevation was 150 µg/dl. TIBC elevation of >150 µg/dl is a favorable predictor of effective ferritin reduction in DFX therapy (hazard ratio 29.6, 95 % confidence interval 4.8-183.6; p < 0.001). DFX therapy with TIBC monitoring may enable the determination of the minimum effective DFX dosage.

Impact of iron overload and potential benefit from iron chelation in low-risk myelodysplastic syndrome

Myelodysplastic syndromes (MDSs) are a group of heterogeneous clonal bone marrow disorders characterized by ineffective hematopoiesis, peripheral blood cytopenias, and potential for malignant transformation. Lower/intermediate-risk MDSs are associated with longer survival and high red blood cell (RBC) transfusion requirements resulting in secondary iron overload. Recent data suggest that markers of iron overload portend a relatively poor prognosis, and retrospective analysis demonstrates that iron chelation therapy is associated with prolonged survival in transfusion-dependent MDS patients. New data provide concrete evidence of iron's adverse effects on erythroid precursors in vitro and in vivo. Renewed interest in the iron field was heralded by the discovery of hepcidin, the main serum peptide hormone negative regulator of body iron. Evidence from β-thalassemia suggests that regulation of hepcidin by erythropoiesis dominates regulation by iron. Because iron overload develops in some MDS patients who do not require RBC transfusions, the suppressive effect of ineffective erythropoiesis on hepcidin may also play a role in iron overload. We anticipate that additional novel tools for measuring iron overload and a molecular-mechanism-driven description of MDS subtypes will provide a deeper understanding of how iron metabolism and erythropoiesis intersect in MDSs and improve clinical management of this patient population.

Ferritin as prognostic marker in multiple myeloma patients undergoing autologous transplantation

Serum ferritin reflects body iron stores, but this correlation is dissociated in inflammation. Ferritin has been shown to be prognostically relevant in breast cancer and in patients with hematologic malignancies undergoing autologous or allogeneic stem cell transplantation. In the present study, we evaluated the prognostic relevance of pretransplant ferritin levels in 137 patients with myeloma (median age: 56 years) subjected to autologous stem cell transplantation in our institution between 1994 and 2010. After completion of induction therapy, a minority of patients had increased β₂-microglobulin (β2M) (> 3.5 mg/L: 30.6%) or low albumin (≤ 3.5 g/dL: 6.8%). Median overall survival from transplantation was 83.9 months. Pretransplant ferritin level was an independent prognostic marker in multivariate analyses (including age and ferritin levels albumin) for progression-free and overall survival and retained prognostic significance in a stepwise backward regression. Iron-independent effects of ferritin in myeloma should be prospectively investigated in preclinical and clinical studies.

Improvement of iron-mediated oxidative DNA damage in patients with transfusion-dependent myelodysplastic syndrome by treatment with deferasirox

Myelodysplastic syndrome (MDS) is characterized by dysplastic and ineffective hematopoiesis, peripheral blood cytopenias, and a risk of leukemic transformation. Most MDS patients eventually require red blood cell (RBC) transfusions for anemia and consequently develop iron overload. Excess free iron in cells catalyzes generation of reactive oxygen species that cause oxidative stress, including oxidative DNA damage. However, it is uncertain how iron-mediated oxidative stress affects the pathophysiology of MDS. This study included MDS patients who visited our university hospital and affiliated hospitals (n=43). Among them, 13 patients received iron chelation therapy when their serum ferritin (SF) level was greater than 1000 ng/mL or they required more than 20 RBC transfusions (or 100 mL/kg of RBC). We prospectively analyzed 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in peripheral blood mononuclear cells (PBMC) obtained from MDS patients before and after iron chelator, deferasirox, administration. We showed that the 8-OHdG levels in MDS patients were significantly higher than those in healthy volunteers and were positively correlated with SF and chromosomal abnormalities. Importantly, the 8-OHdG levels in PBMC of MDS patients significantly decreased after deferasirox administration, suggesting that iron chelation reduced oxidative DNA damage. Thus, excess iron could contribute to the pathophysiology of MDS and iron chelation therapy could improve the oxidative DNA damage in MDS patients.