Acute megakaryoblastic leukemia in a patient with xeroderma pigmentosum: discussion of pathophysiological, prognostic, and toxicological aspects.

BACKGROUND: Xeroderma pigmentosum (XP) is an autosomal recessive inherited disease characterized by extreme sensitivity to sunlight. Normal individuals harboring XPD polymorphisms are at increased risk for developing acute lymphoblastic leukemia and acute myeloid leukemia (AML).

CASE REPORT: A 33-year-old male XP patient was diagnosed with acute megakaryoblastic leukemia with a complex karyotype. He received standard induction chemotherapy with cytarabine and daunorubicin. After the first cycle of chemotherapy, persistence of blasts was seen and a re-induction cycle with cytarabine, fludarabine, and idarubicin was administered resulting in complete remission. Due to the high-risk profile of his AML, allogeneic stem cell transplantation (SCT) was performed. Following a conditioning regimen with busulfan and cyclophosphamide, the patient received a matched related SCT from his HLA-identical sister. Despite the existence of his DNA repair gene mutation, chemotherapy was normally tolerated by the patient. Unfortunately, he died due to severe sepsis and relapse of AML 45 days after SCT.

CONCLUSION: The XPD mutation in our patient may have contributed to the emergence of his high-risk AML. Despite the existence of a DNA repair gene mutation, our XP patient could be treated with full doses of AML-type chemotherapy including allogeneic SCT without encountering unusual toxicity.