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Published on: November 3, 2018
Idiopathic cytopenia of undetermined significance (ICUS) versus low risk MDS: the diagnostic interface
Friedrich Wimazal1, Christa Fonatsch, Renate Thalhammer
1Department of Internal Medicine I, Division of Hematology & Hemostaseology, Medical University of Vienna, Vienna, Austria.
Insights
Diagnosing low-risk myelodysplastic syndromes (MDS) with mild cytopenia is challenging. This study proposes "idiopathic cytopenia of undetermined significance" (ICUS) for unexplained cytopenia, recommending long-term follow-up.
Area of Science:
- Hematology
- Oncology
- Clinical Pathology
Background:
- Diagnosing low-risk myelodysplastic syndromes (MDS) can be difficult in patients presenting with mild cytopenia.
- Unexplained cytopenia without definitive signs of myeloid neoplasm poses a diagnostic challenge.
Purpose of the Study:
- To describe a cohort of patients with unexplained cytopenia.
- To propose a new term, idiopathic cytopenia of undetermined significance (ICUS), for these cases.
- To assess the clinical evolution of patients with ICUS.
Main Methods:
- Retrospective analysis of 10 patients with mild to marked unexplained cytopenia.
- Bone marrow cytogenetic analysis (karyotyping) was performed.
- Clinical follow-up was conducted for at least 6 months.
Main Results:
- Two patients showed karyotype abnormalities (trisomy 14; monosomy 7) in a subset of bone marrow cells.
- Two patients progressed to overt MDS, including the one with monosomy 7.
- The remaining patients did not develop MDS during the follow-up period.
Conclusions:
- The term idiopathic cytopenia of undetermined significance (ICUS) is proposed for unexplained cytopenia.
- Long-term follow-up is crucial for evaluating the evolution of ICUS.
- Early identification and monitoring may aid in the diagnosis of low-risk MDS.
Abstract:
It may sometimes be difficult to diagnose low risk MDS in patients with mild cytopenia. We report on 10 patients with mild to marked, unexplained cytopenia without definitive signs of a myeloid neoplasm. In two patients, a karyotype-abnormality (trisomy 14; monosomy 7) was detected in a small subset of bone marrow cells. Progression to overt MDS was seen in two patients including the one with monosomy 7. In the remaining cases, no MDS developed in a follow-up of at least 6 months. The phrase "idiopathic cytopenia of undetermined significance (ICUS)", as also suggested by Mufti and co-workers, is proposed and long term follow-up is recommended to assess the evolution.
