Evolution of severe (transfusion-dependent) anaemia in myelodysplastic syndromes with 5q deletion is characterized by a macrophage-associated failure of the eythropoietic niche.

Evolution of erythrocyte transfusion-dependent (RBC-TD) anaemia associated with haploinsufficiency of the ribosomal protein subunit S14 gene (RPS14) is a characteristic complication of myelodysplastic syndromes (MDS) with del(5q) [MDS.del(5q)]. Evaluating 39 patients with MDS.del(5q), <5% of anaemia progression was attributable to RPS14-dependent alterations of normoblasts, pro-erythroblasts, or CD34+ CD71+ precursors. Ninety-three percent of anaemia progression and 70% of the absolute decline in peripheral blood Hb value were attributable to disappearance of erythroblastic islands (Ery-Is). Ery-Is loss occurred independently of blast excess, TP53 mutation, additional chromosome aberrations and RPS14-dependent alterations of normoblasts and pro-erythroblasts. It was associated with RPS14-dependent intrinsic (S100A8+ ) and extrinsic [tumour necrosis factor α (TNF-α)-overproduction] alterations of (CD169+ ) marrow macrophages (p < 0.00005). In a mouse model of RPS14 haploinsufficiency, Ery-Is disappeared to a similar degree: approximately 70% of Ery-Is loss was related to RPS14-dependent S100A8 overexpression of marrow macrophages, less than 20% to that of CD71high Ter119- immature precursors, and less than 5% to S100A8/p53 overexpression of normoblasts or pro-erythroblasts. Marked Ery-Is loss predicted reduced efficacy (erythrocyte transfusion independence) of lenalidomide therapy (p = 0.0006). Thus, erythroid hypoplasia, a characteristic complication of MDS.del(5q), seems to result primarily from a macrophage-associated failure of the erythropoietic niche markedly reducing the productive capacity of erythropoiesis as the leading factor in anaemia progression and evolution of RBC-TD in MDS.del(5q).

Chromosome 5 harbors two independent deletion hotspots at 5q13 and 5q21 that characterize biologically different subsets of aggressive prostate cancer.

Deletion of chromosome 5q is common in prostate cancer and is linked to aggressive disease. Most previous studies focused on 5q21 where CHD1 is located, but deletion of mapping studies has identified a second deletion hotspot at 5q13. To clarify the prevalence and clinical relevance of 5q13 deletions and to determine the relative importance of 5q13 and 5q21 abnormalities, a tissue microarray containing samples from 12 427 prostate cancers was analyzed by fluorescence in situ hybridization. Deletion of 5q13 and 5q21 was found in 13.5% and 10%, respectively, of 7932 successfully analyzed cancers. Deletion was restricted to 5q13 in 49.4% and to 5q21 in 32.0% of cancers with a 5q deletion. Only 18.6% of 5q-deleted cancers had deletions of both loci. Both 5q13 and 5q21 deletions were significantly linked to advanced tumor stage, high Gleason grade, nodal metastasis and early biochemical recurrence (P < .005 each). Cancers with co-deletion of 5q13 and 5q21 had a worse prognosis than cancers with isolated 5q13 or 5q21 deletion (P = .0080). Comparison with TMPRSS2:ERG fusion status revealed that 5q21 deletions were tightly linked to ERG negativity (P < .0001) while 5q13 deletions were unrelated to the ERG status. In summary, 5q13 deletion and 5q21 deletion are common, but independent genomic alterations with different functional effects lead to aggressive prostate cancer.

Nuclear translocation of PKC-α is associated with cell cycle arrest and erythroid differentiation in myelodysplastic syndromes (MDSs).

PI-PLCß1 is involved in cell proliferation, differentiation, and myelodysplastic syndrome (MDS) pathogenesis. Moreover, the increased activity of PI-PLCß1 reduces the expression of PKC-α, which, in turn, delays the cell proliferation and is linked to erythropoiesis. Lenalidomide is currently used in low-risk patients with MDS and del(5q), where it can suppress the del(5q) clone and restore normal erythropoiesis. In this study, we analyzed the effect of lenalidomide on 16 patients with low-risk del(5q) MDS, as well as del(5q) and non-del(5q) hematopoietic cell lines, mainly focusing on erythropoiesis, cell cycle, and PI-PLCß1/PKC-α signaling. Overall, 11 patients were evaluated clinically, and 10 (90%) had favorable responses; the remaining case had a stable disease. At a molecular level, both responder patients and del(5q) cells showed a specific induction of erythropoiesis, with a reduced γ/ß-globin ratio, an increase in glycophorin A, and a nuclear translocation of PKC-α. Moreover, lenalidomide could induce a selective G0/G1 arrest of the cell cycle in del(5q) cells, slowing down the rate proliferation in those cells. Altogether, our results could not only better explain the role of PI-PLCß1/PKC-α signaling in erythropoiesis but also lead to a better comprehension of the lenalidomide effect on del(5q) MDS and pave the way to innovative, targeted therapies.-Poli, A., Ratti, S., Finelli, C., Mongiorgi, S., Clissa, C., Lonetti, A., Cappellini, A., Catozzi, A., Barraco, M., Suh, P.-G., Manzoli, L., McCubrey, J. A., Cocco, L., Follo, M. Y. Nuclear translocation of PKC-α is associated with cell cycle arrest and erythroid differentiation in myelodysplastic syndromes (MDSs).

ADGRV1 is implicated in myoclonic epilepsy.

OBJECTIVE: To investigate the significance of variation in ADGRV1 (also known as GPR98, MASS1, and VLGR1), MEF2C, and other genes at the 5q14.3 chromosomal locus in myoclonic epilepsy. METHODS: We studied the epilepsy phenotypes of 4 individuals with 5q14.3 deletion and found that all had myoclonic seizures. We then screened 6 contiguous genes at 5q14.3, MEF2C, CETN3, MBLAC2, POLR3G, LYSMD3, and ADGRV1, in a 95-patient cohort with epilepsy and myoclonic seizures. Of these genes, point mutations in MEF2C cause a phenotype involving seizures and intellectual disability. A role for ADGRV1 in epilepsy has been proposed previously, based on a recessive mutation in the Frings mouse model of audiogenic seizures, as well as a shared homologous region with another epilepsy gene, LGI1. RESULTS: Six patients from the myoclonic epilepsy cohort had likely pathogenic ultra-rare ADGRV1 variants, and statistical analysis showed that ultra-rare variants were significantly overrepresented when compared to healthy population data from the Genome Aggregation Database. Of the remaining genes, no definite pathogenic variants were identified. SIGNIFICANCE: Our data suggest that the ADGRV1 variation contributes to epilepsy with myoclonic seizures, although the inheritance pattern may be complex in many cases. In patients with 5q14.3 deletion and epilepsy, ADGRV1 haploinsufficiency likely contributes to seizure development. The latter is a shift from current thinking, as MEF2C haploinsufficiency has been considered the main cause of epilepsy in 5q14.3 deletion syndrome. In cases of 5q14.3 deletion and epilepsy, seizures likely occur due to haploinsufficiency of one or both of ADGRV1 and MEF2C.

Interstitial deletion 5p14.1-p15.2 and 5q14.3-q23.2 in a patient with clubfoot, blepharophimosis, arthrogryposis, and multiple congenital abnormalities.

Interstitial deletions of the short and long arms of chromosome 5 are rare cytogenetic abnormalities. The 5p distal deletion is a genetic disorder characterized by a high-pitched cat-like cry, microcephaly, epicanthal folds, micrognathia, severe intellectual disability and motor delays. Previously, more than 46 patients with the 5q deletion have been reported. Here, we report de novo interstitial deletions involving 5p14.1-p15.2 and 5q14.3-q23.2 in a patient with multiple congenital abnormalities, including blepharophimosis, arthrogryposis, short neck, round face, pelvic kidney, agenesis of the corpus callosum, and clubfoot. The deletions were characterized using GTG banding and aCGH microarray analysis. Concurrent 5p and 5q interstitial deletions in humans have not been previously reported. We also discussed the relationship between the 5q deleted region and clubfeet.

Peripheral blood cytogenetics allows treatment monitoring and early identification of treatment failure to lenalidomide in MDS patients: results of the LE-MON-5 trial.

Transfusion-dependent patients with low- or intermediate-1-risk myelodysplastic syndrome, <5% bone marrow (BM) blasts and isolated 5q-deletion received lenalidomide within the German MDS study group phase-II clinical trial LE-MON-5 (EudraCT:2008-001866-10) of the University of Duesseldorf, Germany. Cytogenetic monitoring was performed by chromosome banding analyses (CBA) of BM cells and fluorescence in situ hybridization (FISH) analyses of peripheral blood (PB) mononuclear CD34+ cells using extended probe panels. Out of 144 patients screened for study enrollment, 24% failed to meet inclusion criteria due to cytogenetic findings. Eighty-seven patients were followed with a median observation time of 30 months. Cytogenetic response detected by FISH and CBA in 74 and 66% of patients, respectively, was predictive for hematologic response as well as of high prognostic relevance. After 2 years, AML rate was 8% for all patients. Karyotype evolution was detected in 21 (FISH)-34% (CBA) of patients associated with significantly shorter AML-free survival. Disease progression was first detectable on the cytogenetic level on average 5-6 months before recurrence of transfusion dependence. Our data show for the first time in a prospective setting that a cytogenetic monitoring from the PB helps to early identify treatment failure and progressive disease in lenalidomide-treated patients to improve clinical management. TRIAL REGISTRATION: EudraCT:2008-001866-10.

Myelodysplastic syndrome with 5q deletion following IgM monoclonal gammopathy, showing gene mutation MYD88 L265P.

Patients affected by monoclonal gammopathy of undetermined significance (MGUS) very rarely develop a myelodysplastic syndrome (MDS). However, it was also demonstrated that MGUS patients had a significantly increased risk of developing MDS compared to the general population. We report a case of 5q-syndrome following a MGUS IgMk with mutation of MYD88 L256P. To our knowledge, this is the first case of del(5q) MDS following MGUS IgMk with the MYD88 L256P mutation in which there is coexistence of the markers of the two clonal diseases, but as an expression of distinct pathological features.

Lenalidomide performance in the real world: patterns of use and effectiveness in a Medicare population with myelodysplastic syndromes.

BACKGROUND: Lenalidomide is approved for the treatment of anemia with transfusion dependence (TD) in patients with lower-risk myelodysplastic syndrome (MDS) with 5q deletion (del5q-MDS), but its "real-life" use and effect on transfusion needs are unclear. In the current study, the authors examined its use in the Medicare population. METHODS: Patients with MDS who were enrolled in Medicare Parts A, B, and D were identified using International Classification of Diseases 9-Clinical Modification (ICD-9) codes from 100% Medicare claims from 2006 through 2008. Patients were followed until the end of the study or death. Claims were used to determine time to initiation of lenalidomide, daily dose, duration, and other MDS therapies. Transfusion status was defined each week based on transfusion use in rolling 8-week period: TD, required transfusions during 2 weeks, separated by ≥ 3 weeks; transfusion user (TU), 1 transfusion; and transfusion independence (TI), no transfusions. RESULTS: A total of 753 of 23,855 patients (3.2%) received lenalidomide, including 31% of 470 patients with del5q-MDS. At the time of lenalidomide initiation, 33% of patients were TD, 31% were TU, and 36% were TI. The median time to lenalidomide initiation was shorter for patients with del5q-MDS than for other lower-risk patients (8 weeks vs 20 weeks; P < .01). The percentage of patients with del5q-MDS receiving lenalidomide increased over time. Lenalidomide initiation was found to be negatively associated with older age and baseline diabetes, stroke, and renal disease. During the observation period, 44% of TU/TD patients (53% of the patients with del5q-MDS) achieved reductions in transfusion use; among TD patients receiving ≥ 3 cycles, 77% reduced their transfusion use and 40% achieved TI. CONCLUSIONS: To the authors' knowledge, the current study is the first report of lenalidomide use in a large Medicare-enrolled population with MDS. Reductions in transfusion rates were overall consistent with data from clinical trials. Response rates were higher when ≥ 3 lenalidomide cycles were received.

Lenalidomide treatment of Japanese patients with myelodysplastic syndromes with 5q deletion: a post-marketing surveillance study.

Lenalidomide was approved in Japan for the treatment of patients with myelodysplastic syndromes associated with a 5q deletion (del 5q-MDS) in August 2010. A post-marketing surveillance (PMS) study enrolled 173 patients with del 5q-MDS who started lenalidomide treatment between August 2010 and September 2011 (mean ± standard deviation [SD] age 72.4 ± 9.0 years) and observed for up to 6 cycles or 6 months. Adverse drug reactions (ADRs) and serious ADRs were reported in 78.0% and 50.9% of patients. The most commonly observed ADRs were thrombocytopenia or platelet count decreased (46.2%), neutropenia or neutrophil count decreased (42.2%), and rash (23.1%). Of 114 patients who were red blood cell transfusion-dependent at baseline, 39 (34.2%) achieved transfusion independence during lenalidomide treatment. Of 173 patients, 19 (11.0%) had confirmed acute myeloid leukemia (AML) progression during the study. Moreover, long-term follow-up (3 years) was available for 68 of the 173 patients, of whom 12 (17.6%) progressed to AML during the additional period. This PMS study investigated the safety and effectiveness of lenalidomide in patients with del 5q-MDS. No new safety concerns were noted in routine clinical use in Japan and no evidence was found for an increased risk of AML progression following lenalidomide treatment.

APC-Related Phenotypes and Intellectual Disability in 5q Interstitial Deletions: A New Case and Review of the Literature.

The 5q deletion syndrome is a relatively rare condition caused by the monoallelic interstitial deletion of the long arm of chromosome 5. Patients described in literature usually present variable dysmorphic features, behavioral disturbance, and intellectual disability (ID); moreover, the involvement of the APC gene (5q22.2) in the deletion predisposes them to tumoral syndromes (Familial Adenomatous Polyposis and Gardner syndrome). Although the development of gastrointestinal tract malignancies has been extensively described, the genetic causes underlying neurologic manifestations have never been investigated. In this study, we described a new patient with a 19.85 Mb interstitial deletion identified by array-CGH and compared the deletions and the phenotypes reported in other patients already described in the literature and the Decipher database. Overlapping deletions allowed us to highlight a common region in 5q22.1q23.1, identifying KCNN2 (5q22.3) as the most likely candidate gene contributing to the neurologic phenotype.

When Clinico-Morphological and Molecular Studies Tell Different Stories: A Case of Myelodysplastic Syndrome.

Myelodysplastic syndromes (MDSs) are clonal hematopoietic stem cell disorders characterized by cytopenias, dysplasia in one or more of the major myeloid cell lines, ineffective hematopoiesis, with cellular marrow, and risk for leukemic transformation. We present a case of a 66-year-old male with a history of multiple packed red blood cell (PRBC) transfusions. Routine investigations, bone marrow aspiration, and biopsy were done. The clinical and morphological findings raised suspicion of MDS with isolated del (5q), so cytogenetics was done. When cytogenetics was done, there was a big mismatch in finding between clinical, morphological, and molecular findings which brought a major change in prognosis as well as treatment. It is, therefore, very essential to not rely only on the clinical and morphological findings to reach a diagnosis. Molecular findings play a pivotal role to come to a final conclusion.

Myelodysplastic Syndromes with Isolated del(5q): Value of Molecular Alterations for Diagnostic and Prognostic Assessment.

Myelodysplastic syndromes (MDS) are a group of clonal hematological neoplasms characterized by ineffective hematopoiesis in one or more bone marrow cell lineages. Consequently, patients present with variable degrees of cytopenia and dysplasia. These characteristics constitute the basis for the World Health Organization (WHO) classification criteria of MDS, among other parameters, for the current prognostic scoring system. Although nearly half of newly diagnosed patients present a cytogenetic alteration, and almost 90% of them harbor at least one somatic mutation, MDS with isolated del(5q) constitutes the only subtype clearly defined by a cytogenetic alteration. The results of several clinical studies and the advances of new technologies have allowed a better understanding of the biological basis of this disease. Therefore, since the first report of the "5q- syndrome" in 1974, changes and refinements have been made in the definition and the characteristics of the patients with MDS and del(5q). Moreover, specific genetic alterations have been found to be associated with the prognosis and response to treatments. The aim of this review is to summarize the current knowledge of the molecular background of MDS with isolated del(5q), focusing on the clinical and prognostic relevance of cytogenetic alterations and somatic mutations.

Pathophysiologic and clinical implications of molecular profiles resultant from deletion 5q.

BACKGROUND: Haploinsufficiency (HI) resulting from deletion of the long arm of chromosome 5 [del(5q)] and the accompanied loss of heterozygosity are likely key pathogenic factors in del(5q) myeloid neoplasia (MN) although the consequences of del(5q) have not been yet clarified. METHODS: Here, we explored mutations, gene expression and clinical phenotypes of 388 del(5q) vs. 841 diploid cases with MN [82% myelodysplastic syndromes (MDS)]. FINDINGS: Del(5q) resulted as founder (better prognosis) or secondary hit (preceded by TP53 mutations). Using Bayesian prediction analyses on 57 HI marker genes we established the minimal del(5q) gene signature that distinguishes del(5q) from diploid cases. Clusters of diploid cases mimicking the del(5q) signature support the overall importance of del(5q) genes in the pathogenesis of MDS in general. Sub-clusters within del(5q) patients pointed towards the inherent intrapatient heterogeneity of HI genes. INTERPRETATION: The underlying clonal expansion drive results from a balance between the "HI-driver" genes (e.g., CSNK1A1, CTNNA1, TCERG1) and the proapoptotic "HI-anti-drivers" (e.g., RPS14, PURA, SIL1). The residual essential clonal expansion drive allows for selection of accelerator mutations such as TP53 (denominating poor) and CSNK1A1 mutations (with a better prognosis) which overcome pro-apoptotic genes (e.g., p21, BAD, BAX), resulting in a clonal expansion. In summary, we describe the complete picture of del(5q) MN identifying the crucial genes, gene clusters and clonal hierarchy dictating the clinical course of del(5q) patients. FUNDING: Torsten Haferlach Leukemia Diagnostics Foundation. US National Institute of Health (NIH) grants R35 HL135795, R01HL123904, R01 HL118281, R01 HL128425, R01 HL132071, and a grant from Edward P. Evans Foundation.

Lenalidomide for anemia correction in lower-risk del(5q) myelodysplastic syndrome patients of Asian ethnicity.

BACKGROUND: To estimate real-world outcomes in East Asian populations, we conducted a nationwide retrospective analysis of the efficacy and safety of lenalidomide for del(5q) myelodysplastic syndrome (MDS) patients with transfusion-dependent anemia in Korea. METHODS: Patients aged ≥19 years who had received lenalidomide for the treatment of lower-risk, red blood cell (RBC) transfusion-dependent del(5q) MDS were selected. A filled case report form (CRF) with information from electronic medical records was requested from members of the acute myeloid leukemia (AML)/MDS Working Party of the Korean Society of Hematology. All the CRFs were gathered and analyzed. RESULTS: A total of 31 patients were included in this study. Of 28 evaluable patients, 19 (67.9%) achieved RBC transfusion independence (RBC-TI). Female sex and the development of thrombocytopenia during treatment were associated with achieving RBC-TI. The most common non-hematologic toxicities were pruritus, fatigue, and rashes. All non-hematologic toxicities of grades ≥3 were limited to rash (12.9%) and pruritus (6.5%). Dose reduction was required in 15 of the 19 responders (78.9%). The most common final stable dosing schedule for the responders was 5 mg once every other day (31.6%). CONCLUSION: Lenalidomide efficacy and tolerability were similar in the Asian del(5q) MDS patients and western patients. Dose reduction during treatment was common, but it was not associated with inferior outcomes.

5q Deletion Myelodysplastic Syndrome in a Young Male Patient.

Myelodysplastic syndromes (MDS) are a diverse group of hematopoietic stem cell malignancies with various phenotypic variability that are categorized by abnormal differentiation of one or multiple cell lines of the bone marrow. A large part of the phenotypic heterogeneity is in part due to the wide set of genetic defects related to MDS. Though clinically, MDS is centered on diagnostic measures that do not incorporate molecular genetic data, an isolated deletion of the long arm of chromosome 5 (del(5q)) is the only subset of MDS to be identified by genetic defects. This distinctive phenotype is termed 5q-syndrome. We report a case of a 25-year-old with a past medical history of polydactyly, severe anemia, and thrombocytopenia who presented to the emergency department with a chief complaint of weakness and fatigue. Bone marrow biopsy showed myeloid neoplasm with complex genetic abnormalities, nearly 100% hyperplastic marrow with marked trilineage dysplasia, relative myeloid hyperplasia with increased abnormal eosinophilic precursors, erythroid left shift, and atypical megakaryocytes. Fluorescence in situ hybridization (FISH) panel showed deletion of 5q-. Herein, we address the clinical course and morphological characteristics as well as possible therapeutic options for 5q syndrome.

Philadelphia chromosome positive chronic myeloid leukemia with 5q deletion at diagnosis.

BACKGROUND: Although, molecular genetic analyses became more and more important to guide therapy decisions in leukemia, banding cytogenetic analysis has retained its vital role in diagnosis and monitoring of chronic myeloid leukemia (CML), by quick and easy enabling identification of pathognomonic Philadelphia chromosome (Ph). CASE PRESENTATION: A 45 year old female presented with characteristic hematological features of CML in chronic phase; cytogenetic studies revealed the presence of the typical Ph and a deletion of almost entire long arm of a chromosome 5. CONCLUSION: 5q deletions have rarely been reported in CML. Those seen yet were either associated with tyrosine kinase inhibitor therapy or detected post allogeneic stem cell transplantation. To our knowledge, this is the first case of Ph positive CML accompanied by a 5q deletion.

An adult female with 5q34-q35.2 deletion: A rare syndromic presentation of left ventricular non-compaction and congenital heart disease.

Terminal and interstitial deletions of the 5q35 region have been rarely reported in the literature. While a delineated phenotype has been suggested, the range of clinical presentations is unknown due to overall rarity. Cardiac features are of interest because haploinsufficiency of the NKX2-5 gene, located at 5q35.1, has been implicated in congenital heart defects with or without conduction disease. Previous case reports of similar deletions included primarily infants and young children and longitudinal clinical and developmental phenotypic data are currently lacking. We report on a 24-year-old female, the first described adult case with an interstitial 5q34-q35.2 deletion and the third reported case where the cytogenetic abnormality is specified using chromosomal microarray analysis. We include details of her cardiac, developmental, and craniofacial phenotypes. The patient is diagnosed with mild intellectual disability, autism spectrum disorder, limitations in fine and gross motor skills, minor malformations of facial features, and a cardiac phenotype with conduction disease, congenital heart disease, and left ventricular non-compaction dilated cardiomyopathy. This report also reviews the overlapping features in previously published 5q35 deletions and, importantly, provides deeper insight into distal 5q deletions.

Treatment of Patients With Myelodysplastic Syndrome With Lenalidomide in Clinical Routine in Austria.

BACKGROUND: Lenalidomide has demonstrated remarkable efficacy for therapy of lower-risk myelodysplastic syndromes (MDS) associated with 5q(-). The present evaluation aimed to describe the characteristics and outcomes of low-risk MDS patients treated with lenalidomide in Austria. PATIENTS AND METHODS: For this retrospective, multicenter, observational analysis of MDS patients who received lenalidomide, data were collected at various hospitals in Austria over a period of 3 years. MDS classification, previous and current MDS therapies, and outcome and safety of lenalidomide were evaluated. RESULTS: Forty-six percent of the patients (n = 23) had a 5q(-) syndrome, while 12% (n = 6) exhibited 5q(-) plus additional aberrations or isolated 5q(-) but ≥ 5% blasts in the bone marrow (10%, n = 5). The remaining 32% of patients (n = 16) had MDS with other World Health Organization classifications. Seventy percent belonged to lower International Prognostic Scoring System risk classes. Sixteen centers participated, involving a total of 50 patients. Most frequently used lenalidomide doses were 10 mg and 5 mg on days 1 to 21 of a 28-day cycle. Seventy-five percent of the patients received 11 months of treatment, with a median therapy period of 3.5 months; median follow-up was 3.9 months (range, 0-26 months). Response rate, defined as transfusion independence during the 2 months after lenalidomide therapy, was 64%. Median overall survival was not reached. CONCLUSION: Lenalidomide was well tolerated and is an effective and well-tolerated option for therapy of patients with 5q(-) syndrome but also lower-risk MDS patients with other World Health Organization classifications in clinical practice.

Early lenalidomide treatment for low and intermediate-1 International Prognostic Scoring System risk myelodysplastic syndromes with del(5q) before transfusion dependence.

Lenalidomide is approved for the treatment of transfusion-dependent (TD) del(5q) myelodysplastic syndromes (MDS). However, few data are available in patients with transfusion-independent (TI) del(5q) MDS. In the first, observational, part of this 2-part study, we assessed the impact of transfusion dependence on overall survival (OS) and non-leukemic death in untreated del(5q) MDS patients who were TD (n = 136), TI with hemoglobin (Hb) ≥10 mg/dL (n = 88), or TI with Hb <10 mg/dL (n = 96). In the second, interventional, part we assessed the quality-of-life (QoL) benefits and clinical efficacy of lenalidomide (10 mg/day) in 12 patients with TI del(5q) MDS and Hb <10 mg/dL. In the untreated population, OS was significantly longer in TI than in TD patients (TI [Hb ≥10 g/dL], 108 months; TI [Hb <10 g/dL], 77 months; TD, 44 months). Transfusion dependence also negatively impacted non-leukemic death rates. In the interventional part of the study, baseline Hb levels were found to correlate significantly with physical (R = 0.666, P = 0.035) and fatigue (R = 0.604, P = 0.049) QoL scores. Median physical QoL scores improved significantly after 12 weeks' treatment with lenalidomide (+12.5; P = 0.020). Evaluable TI patients experienced early increases in Hb levels, and all attained an erythroid response. Our findings suggest that TI patients with moderate anemia may benefit from early treatment with lenalidomide.