A biopsy showed a superficial and deep, perivascular, atypical mononuclear cell infiltrate with CD68, CD43, and myeloperoxidase positivity. A complete blood count revealed leukocytosis with monocytosis and immature granulocytes. A bone marrow biopsy showed acute myelomonocytic leukemia.
The patient received aggressive multiagent chemotherapy. After a disease-free period of 8 months, he subsequently developed a transient erythematous, macular eruption that prompted a repeat work-up. He was diagnosed with a relapse of his leukemia and is currently undergoing treatments with the monoclonal antibody, gemtuzumab ozogamicin.
“Leukemia cutis occurs in a significant minority of patients who have been previously diagnosed with leukemia or in whom the work-up for systemic illness has already begun,” said Adrian Guevara, M.D., who presented this case in a poster session at the annual meeting of the American Academy of Dermatology, “but only rarely is it the presenting sign of a myeloproliferative or myelodysplastic state in an otherwise asymptomatic patient.”
The lesions are the result of an infiltration of neoplastic cells into the epidermis and dermis; they occur in about 30% of leukemia patients. They most frequently appear as nonspecific, firm or rubbery papules, nodules, or plaques, which can range from flesh-colored to plum-colored. They can masquerade as other skin diseases including erythema nodosum, mycosis fungoides, erythema annulare centrifugum, urticaria, psoriasis, stasis dermatitis, and chilblains, said Dr. Guevara, a resident at the University of Oklahoma, Oklahoma City.
Early biopsy can provide critical information. For this patient, the skin biopsy was the first clue to underlying malignancy.
An early cutaneous manifestation such as this is usually a marker for advanced disease with involvement of other organs including meninges, Dr. Guevara noted.