The main pathophysiology in this condition is that the hematopoietic stem cells do not mature in a proper fashion to healthy erythrocytes, leukocytes and platelets resulting in low counts of mature cells and abnormal morphology. Thus there are many immature cells which do not function in a proper manner leading to several complications.
MDS an be primary or secondary. Secondary MDS can occur due to several causes like exposure to radiotherapy or cytotoxic chemotherapy for another cancer, intensive pretreatment for patients with autologous bone marrow transplants, viral infection, genetic predisposition or exposure to chemicals like benzene (Emmanuel and Woermann, 2009, Nguyen, 2009). Exposure to heavy metals like lead and mercury can also result in this condition (National Cancer Institute, 2010).
80-90 percent of cases occur in those who are above 60 years of age (American Cancer Society, 2010). The incidence is men in at least 2 times more than in women (Emmanuel and Woermann, 2009). The condition is found worldwide and affects all races and ethnic groups (Emmanuel and Woermann, 2009).
The condition is associated with significant morbidity and mortality. More than 30 percent cases of MDS transform in acute leukemia (National Cancer Institute, 2010). Survival following the diagnosis of MDS is variable and dependent on the prognostic factors (Stone, 2009). The survival can occur from months to years (National Cancer Institute, 2010). In children, the course of the disease is more aggressive and the mean survival is less than 10 months (Tilak et al, 2008).
In many patients, MDS is often detected late due to absence of early symptoms. In some others, routine hematological examination may reveal the condition. Those who have advanced disease present with signs and symptoms related to the cytopenias like shortness of breath, pallor, easy fatigability, easy bruising, uncontrollable bleeding, frequent petechiae, fever and frequent infections (National Cancer