The 5q- syndrome

Are myelodysplastic syndromes "cancer"? Unexpected adverse consequences of linguistic ambiguity

Myelodysplastic syndromes (MDS) are clonal, neoplastic disorders of hematopoietic tissue that convey a guarded prognosis, but physicians vary in whether they refer to MDS as a "cancer" when discussing the diagnosis with patients. Because of past ambiguity about whether MDS is truly a malignancy, confusion about MDS terminology is widespread. Additionally, patients who carry one of the dubious cancer-specific health insurance policies are usually not eligible for financial benefits when they receive a diagnosis of MDS. Likewise, patients with MDS who have been led to believe they do not have a form of cancer by their primary physician may become upset when seeing another health care provider who does refer to MDS in this way. Here, I discuss evidence supporting broader consideration of MDS as a form of malignant neoplasia - i.e., cancer - as well as some of the relevant practical issues.

Current therapeutic uses of lenalidomide in multiple myeloma

Thalidomide has demonstrated a broad spectrum of pharmacological and immunological effects, with potential therapeutic applications that span a wide spectrum of diseases: cancer and related conditions; infectious diseases; autoimmune diseases; dermatological diseases; and other disorders such as sarcoidosis, macular degeneration and diabetic retinopathy. Immunomodulatory derivative lenalidomide has more potent antitumour and anti-inflammatory effects. The molecular mechanisms of antitumour activity of lenalidomide have been extensively studied in multiple myeloma (MM). It directly induces growth arrest and/or apoptosis of even drug-resistant MM cells; inhibits binding of MM cells to bone marrow extracellular matrix proteins and stromal cells; modulates cytokine secretion and inhibits angiogenesis in the bone marrow milieu; and augments host antitumour immunity. Importantly, lenalidomide induces significant clinical responses even in patients with relapsed/refractory MM. Therefore, lenalidomide represents a new class of antitumour agents that is useful in the treatment of MM. Lenalidomide has received fast track designation from the FDA for the treatment of MM and myelodysplastic syndromes.

Drug insight: emerging new drugs in the treatment of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a heterogeneous group of hematopoietic stem cell disorders. Although the currently used classification schemes and prognostic algorithms, which are based predominantly on morphologic assessment of blood and marrow smears, have been shown to be valid for defining disease subgroups, they do not take into consideration the significant biological diversity of MDS. As the numerous pathophysiologic pathways that are involved in MDS are being unraveled, new molecular targets are being identified. Novel and targeted therapeutic agents, including inhibitors of farnesyltransferases and receptor tyrosine kinases, more potent thalidomide analogs and epigenetic therapies, have produced encouraging results and might offer durable benefits to patients with MDS. This review intends to provide a concise report on some of the most up-to-date therapies being investigated in MDS.

Prognosis of patients with del(5q) MDS and complex karyotype and the possible role of lenalidomide in this patient subgroup

The survival of patients with myelodysplastic syndromes is strongly affected by chromosomal abnormalities. Patients with an isolated del(5q31) have a favourable prognosis that worsens with the addition of another chromosomal abnormality. It has been reported that both patients with isolated del(5q31) and those with one single additional chromosomal abnormality achieve hematological and cytogenetic remissions with lenalidomide therapy. Whether this translates into improved overall survival of the patient population is unclear. We analysed data of 25 patients with myelodysplastic syndrome and complex chromosomal abnormalities including del(5q31) and show that their median survival is between 7 and 8 months, irrespective of the medullary blast count. Furthermore, we present data of a patient with complex karyotypic anomalies inclusive of del(5q31) treated with lenalidomide who achieved complete cytogenetic remission. This cytogenetic remission was diagnosed after 6 months, and the hematological response is ongoing at 9 months of therapy at a dose of 5 mg p.o. daily. We conclude that lenalidomide has the potential to induce sustained hematological and cytogenetic remissions in the poor prognosis MDS subgroup of del(5q31) patients with complex chromosomal anomalies and that this is likely to improve overall survival.

Treatment of myelodysplastic syndrome with isolated del(5q) including bands q31-q33 with a combination of all-trans-retinoic acid and tocopherol-alpha: a phase II study

All-trans-retinoic acid (ATRA) alone or in combination with cytokines and vitamins has been shown to stimulate erythropoiesis in low-risk myelodysplastic syndromes (MDS). We performed a phase II study on 29 patients with MDS and isolated del(5q) including bands q31-q33 to determine the efficacy and safety of ATRA in combination with tocopherol-alpha. All patients had low/intermediate-1 risk MDS according to the international prognostic scoring system. They received 45 mg/m(2) ATRA on days 1 to 90, and 90 mg/m(2) on days 91 to 180. Tocopherol dosage was 600 IU three times daily. Twenty-four patients completed dose level I, and 12 patients dose level II. Eighty-six percent of patients experienced side effects. Thirty discontinued the drug treatment due to such events as skin reactions, cheilitis, conjunctivitis, joint pain, creatinine increase, or CNS symptoms. One patient (3%) achieved a major erythroid response resulting in transfusion independence throughout the study. Four patients (14%) achieved a minor erythroid response with >50% reduction of transfusion needs. None of the participants had a cytogenetic response. There was no significant improvement in quality of life among responding patients as measured by the European Organization for the Research and Treatment of Cancer (EORTC) quality of life questionnaire. Based on these results, the combination of ATRA and tocopherol-alpha is not recommended for the treatment of del(5q) MDS.