A rare case of a patient with Gaucher disease type 1 who developed chronic myeloid leukemia — a blood cancer — and was treated simultaneously for both diseases was reported for the first time in Spain.
The case report, “Gaucher disease and chronic myeloid leukemia: first reported patient receiving enzyme replacement and tyrosine kinase inhibitor therapies simultaneously,” was published in the journal Clinical Case Reports.
Gaucher disease is a genetic disorder in which a deficiency of the enzyme glucocerebrosidase leads to the accumulation of a fat molecule called glucosylceramide in different tissues, mainly in macrophages, a type of white blood cell.
The buildup of this molecule in macrophages results in their transformation into so-called “Gaucher cells,” which in turn accumulate in organs such as the spleen, liver, or bone marrow, leading to a variety of symptoms.
Several studies have shown that patients with Gaucher disease have an increased risk of developing cancer, especially blood cancers. However, there are only two reports of Gaucher patients who developed chronic myeloid leukemia (CML), an uncommon type of blood cancer.
CML is caused by a genetic alteration in myeloid stem cells — the cells that give rise to red blood cells, platelets, and most types of white blood cells — in the bone marrow.
This leads to the overproduction of nonfunctional white blood cells, which build up in the bone marrow and start to interfere with the normal production of other blood cells, such as red blood cells and platelets.
Researchers in Zaragoza, Spain, reported a case of a 55-year-old woman who was diagnosed with Gaucher disease type 1, and several years later developed CML.
The woman went to the hospital after a bone fracture. She had low levels of platelets in the blood, an enlarged spleen and liver, bone degeneration, and “Gaucher cells” in her bone marrow — all common signs of Gaucher disease. The diagnosis of Gaucher disease type 1 was confirmed through enzymatic and genetic tests.
She started enzyme replacement therapy (ERT) — 60 U/kg every other week in the first year, then 40 U/kg after — and her disease activity was reduced to minimum levels. After a decade of treatment, the only persistent symptom was bone weakness, especially in the spine.
Ten years after her Gaucher diagnosis, the patient had persistent high levels of white blood cells, but no new symptoms. A bone marrow exam showed abnormalities in a type of white blood cell, and numerous cells resembling the Gaucher cells.
Additional tests revealed the genetic alteration associated with chronic myeloid leukemia, confirming its diagnosis. The research team noted that at the time of her Gaucher disease diagnosis, the patient’s samples showed no signs of that genetic mutation, meaning that it appeared afterwards.
In addition to the enzyme replacement therapy for Gaucher disease, the patient was given Gleevec (imatinib) therapy (400 mg a day) for CML, which resulted in good responses. The combination of both therapies showed no increase in adverse effects, according to the researchers.
However, after 18 months of Gleevec therapy, a genetic mutation leading to resistance to Gleevec was detected, and the therapy was changed to Sprycel (dasatinib) (100 mg a day), which also provided a good therapy response.
The researchers noted that some studies have suggested an association between resistance to cancer therapy and the absence of ceramide, a fat molecule that results from the degradation of glucosylceramide by the glucocerebrosidase enzyme.
Therefore, as ERT increases the levels of glucocerebrosidase, and consequently of ceramide, they believe there is no reason to stop ERT in the presence of CML, and that anti-cancer “strategies to increase the ceramide level on cancer cells offers good approaches.”