Myelodysplastic Syndrome Rare, But May Be Under-diagnosed in Gaucher Type 1 Patients, Study Suggests

Myelodysplastic Syndrome Rare, But May Be Under-diagnosed in Gaucher Type 1 Patients, Study Suggests

Myelodysplastic syndrome (MDS) is rare in people with Gaucher disease type 1 (GD1) but because it is difficult to detect it may lead to under-diagnosis in this patient population, a new study suggests.

Titled, “Gaucher disease, myelodysplastic syndrome and ICUS,” the study was published in the journal Blood Cells, Molecules, and Diseases.

MDS is characterized by cytopenia, which refers to a lower-than-normal number of blood cells, as well as abnormal structure of such cells. It may occur spontaneously or result from radiation or chemotherapy. MDS is particularly common in the elderly and is associated with an increased risk of leukemia.

Cytopenia is common in people with GD1. It usually results from spleen enlargement (hypersplenism) or bone marrow infiltration by Gaucher cells. But since bone marrow testing is not required for the diagnosis of GD or hypersplenism, other potential causes for cytopenia — such as MSD — may be missed.

Researchers described six patients with both MDS and GD1, who were being treated at the Gaucher clinic of the Shaare Zedek Medical Center, in Israel. They were diagnosed with GD1 at a median age of 48 years, then with MDS at a median age of 72 years.

In these six cases (all Ashkenazi Jewish, a population with a high prevalence of GD1), MDS was diagnosed between 1990 and 2019, a period during which more than 600 people with GD were seen at the center.

Of note, diagnostic criteria for MDS have changed during this period. This led to reclassification of three cases as ICUS (idiopathic cytopenia of unknown significance), a pre-MDS condition characterized by unexplained cytopenia. However, clinical features were similar among the six patients, including anemia and thrombocytopenia (low platelet counts). They had had cytopenia for a median of nine years before MDS diagnosis.

Two patients had been exposed to radiation before diagnosis, one due to the Chernobyl nuclear facility accident in 1986, and the other was treated with radiotherapy for a breast tumor. Three were blood transfusion-dependent and three had started enzyme replacement therapy for cytopenia.

Also, three patients had symptoms related to anemia, including weakness and dyspnea, or shortness of breath. None developed acute leukemia, but two had plasma cell dyscrasia (a group of disorders that include multiple myeloma) and one T-cell large granular lymphocyte leukemia.

Five of the six patients died at a median of three  years from the diagnosis of MDS.

Overall, the low prevalence of MDS suggests that this condition is relatively rare among people with GD. Yet, “the diagnosis of MDS in patients with GD may be difficult morphologically due to massive bone marrow infiltration with Gaucher cells,” the researchers wrote.

“This is the first descriptive series on the coexistence of Gaucher disease and MDS,” they added. “The question of the role of Gaucher disease in predisposing or inducing the appearance of MDS in these cases remains unclear.”