Multi-center study enrolling patients suspected or newly diagnosed with myelodysplastic syndromes (MDS), myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN) overlap disorder, or idiopathic cytopenia of undetermined significance (ICUS). Participants will be followed long term. Clinical data, blood, and tissue samples will be collected to establish a biorepository to facilitate the study of the natural history of MDS.

Multi-center, prospective cohort study enrolling patients from centers in the National Cancer Institute (NCI) National Clinical Trials Network (NCTN) and NCI Community Oncology Research Program (NCORP). The accrual period is 5+ years. After central pathology review of registered participants, approximately 2,000 cases of MDS or MDS/MPN overlap disorders, and 500 cases of ICUS will be identified for the longitudinal study cohort and up to 1000 cases will be identified for the cross-sectional cohort. No more than 3500 total participants will be registered. Participants in the longitudinal cohort may be followed for life.

The goal of the National MDS Study is to establish a publicly available resource to facilitate the study of MDS natural history. This will be accomplished through: 1) Creation of a multi-institutional, longitudinal collection of consistently processed and clinically well-annotated blood and tissue specimens collected prospectively from participants with MDS and participants with idiopathic cytopenia of undetermined significance (ICUS); and 2) Support for investigator-initiated studies of MDS that will have high-impact for MDS patients, including basic science, clinical, health outcomes and epidemiological research.

Inclusion Criteria:

• Suspected (e.g., persistent unexplained cytopenia, circulating peripheral blasts etc.) MDS or MDS/MPN overlap disorders and undergoing diagnostic work-up with planned bone marrow assessments, or diagnosed with de novo or therapy-related MDS within 12 months of enrollment per the World Health Organization (WHO) criteria1 and undergoing clinical evaluation and planned bone marrow assessments to confirm MDS or to evaluate disease status
• Bone marrow aspirate expected to be performed within 1 week of registration, and in all cases must be performed no later than 4 weeks after enrollment
• Age 18 or older
• If anemic without prior MDS diagnosis, B12 level, serum folate, mean corpuscular volume (MCV), red cell distribution width (RDW), ferritin, and iron studies (Iron, total iron-binding capacity (TIBC) test, and percent saturation) must be performed within prior 6 months.

Exclusion Criteria:

• Prior treatment for MDS at entry and through the time of the entry bone marrow aspirate
• Treatment with hematopoietic growth factors in prior 6 months
• Diagnosis of a solid tumor or hematologic malignancy within two years prior to enrollment except for in situ cancer of the skin (basal or squamous cell), cervix, bladder, breast, or prostate
• Treatment with radiation therapy in the two years prior to registration
• Non-hormonal treatment for malignancy within the two years prior to registration
• Established hereditary bone marrow failure syndrome
• Known primary diagnosis of aplastic anemia, classical paroxysmal nocturnal hemoglobinuria, amegakaryocytic thrombocytopenic purpura, or large granular lymphocyte leukemia
• Enrolled in the Connect® MDS/AML Disease Registry (NCT01688011)

Patients with suspected MDS or MDS/MPN overlap disorder who are undergoing diagnostic workup and bone marrow assessments, and patients diagnosed with MDS within 6-months of enrollment and undergoing clinical evaluation and bone marrow assessments to confirm MDS or evaluate disease status