Aetiology

• various risk factors have been implicated in the aetiology of MDS (1,2)
  • these include age, male gender, alcohol, cigarette smoking, ionizing radiation, immunosuppressive therapy, viral infection, benzene and other environmental/occupational exposures
    • these risk factors are seen infrequently and are estimated to account for disease in only 20-30% of patients, who are often described as having secondary MDS
    • remainder of idiopathic cases constitute primary MDS
    • the risk of MDS is increased in patients with previous haematological disorders, including aplastic anaemia and paroxysmal nocturnal haemoglobinuria (4)

Chromosomal abnormalities are found in approximately 50% of patients with de novo MDS, and in as many as 90% of patients with MDS secondary to previous chemotherapy or radiotherapy (2,3)

Radiotherapy combined with chemotherapy increases the risk compared with radiotherapy alone. (5)

References:

1. Steensma DP, Bennett JM. The myelodysplastic syndromes: diagnosis and treatment. Mayo Clin Proc. 2006 Jan;81(1):104-30.
2. Haase D, Germing U, Schanz J, et al. New insights into the prognostic impact of the karyotype in MDS and correlation with subtypes: evidence from a core dataset of 2124 patients. Blood. 2007 Dec 15;110(13):4385-95.
3. Wang SA, Ok CY, Kim AS, et al. Myelodysplastic syndromes with no somatic mutations detected by next-generation sequencing display similar features to myelodysplastic syndromes with detectable mutations. Am J Hematol. 2021 Nov;96(11):E420-3
4. Sun L, Babushok DV. Secondary myelodysplastic syndrome and leukemia in acquired aplastic anemia and paroxysmal nocturnal hemoglobinuria. Blood. 2020 Jul 2;136(1):36-49.
5. Kaplan HG, Malmgren JA, Atwood MK. Increased incidence of myelodysplastic syndrome and acute myeloid leukemia following breast cancer treatment with radiation alone or combined with chemotherapy: a registry cohort analysis 1990-2005. BMC Cancer. 2011 Jun 21;11:260.